First measurement of kaonic deuterium X-ray transitions
M. Bazzi, F. Clozza, C. Guaraldo, M. A. Iliescu, A. Scordo, F. Sgaramella, D. Sirghi, F. Sirghi, J. Zmeskal, L. Abbene, C. Amsler, F. Artibani, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, A. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, C. Milardi, P. Moskal, F. Napolitano, H. Ohnishi, K. Piscicchia, F. Principato, M. Silarski, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, E. Widmann, C. Curceanu
abstract
The study of the strong interaction among hadrons at low energies remains one of the key challenges in fundamental physics because of its non-perturbative nature, which makes theoretical descriptions strongly dependent on experimental input. Although substantial progress has been made for systems involving up and down quarks, theoretical models in the strangeness sector continue to face limitations due to the lack of experimental data. Kaonic atoms provide a powerful tool to study the low-energy strong interaction with strangeness through the energy shifts and widths induced on their lowest atomic levels. In this context, kaonic deuterium X-ray spectroscopy has long represented one of the major open challenges in hadronic-atom physics because of its extremely low X-ray yield. This measurement is particularly important because it gives access to the experimentally inaccessible K?n interaction at threshold energy. Here, we report the first observation of kaonic deuterium X-ray transitions, performed with the SIDDHARTA-2 experiment at the DA?NE collider. We determine the strong-interaction shift and width of the 1s level to be ?1s=?810.9?24.5(stat)?2.1(syst)eV and ?1s=812?97(stat)?33(syst)eV, respectively. This measurement constitutes the most precise experimental determination of the K?d strong interaction at threshold and allows discrimination among competing theoretical models. Combined with the kaonic hydrogen measurement, this result provides the experimental input required to determine the isospin-dependent K?N scattering lengths, with implications for the description of the nature of the first predicted hadronic molecular state, the ?(1405), and neutron-rich matter.
Bound-state QED test above the Schwinger limit with kaonic fluorine
F. Clozza, S. Manti, F. Sgaramella, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, A. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. A. Iliescu, P. Indelicato, M. Iwasaki, A. Khreptak, J. Marton, P. Moskal, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, J. Sommerfeldt, A. Spallone, K. Toho, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
Kaonic atoms, formed when a negatively charged kaon replaces an electron in an atomic orbit, provide access to bound-state quantum electrodynamics (BSQED) in electromagnetic fields far stronger than in ordinary atoms. Here, we report an experimental test of BSQED in a regime where the mean Coulomb field exceeds the Schwinger limit. Using high-precision x-ray spectroscopy of kaonic fluorine with the SIDDHARTA-2 experiment at DANE, corresponding to an integrated luminosity of 22.4 pb, we observe transitions involving the 4f and 3d levels, probing field-to-Schwinger-limit ratios of 1.11 and 3.70, respectively. The measured transition energies agree with state-of-the-art Dirac-Fock calculations. In particular, the 5g-4f transition showing a residual of 5.8 4.7 (stat.) 5.5 (syst.) eV and a 9 sensitivity to QED contributions. These results provide a direct test of BSQED in the strong-field regime of QED above the Schwinger limit, opening a new avenue for precision studies in extreme electromagnetic fields.
Kaonic Atom X-ray Spectroscopy: From SIDDHARTA-2 to the EXKALIBUR Program
F. Sgaramella, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, A. Clozza, F. Clozza, R. Del Grande, L. De Paolis, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, T. Hashimoto, M. A. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, H. Ohnishi, F. Principato, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, J. Zmeskal, C. Curceanu
abstract
X-ray spectroscopy of kaonic atoms offers a unique experimental window on the interplay between low-energy strong interaction and precision atomic physics studies. This article reviews the scientific progress achieved with SIDDHARTA-2 at DAFNE and discusses how it shapes the next generation measurements. Particular emphasis is given to EXKALIBUR, a multifacility program designed to perform measurements of kaon-nucleus interactions across the periodic table and to extend kaonic atom spectroscopy toward precision tests of bound-state QED and the charged-kaon mass extraction. The first proposed strong interaction campaign at J-PARC aims to investigate kaonic atoms with solid Li, Be, and B targets using new 1-mm-thick Silicon Drift Detectors and high-resolution TES microcalorimeters, exploiting isotope pairs to isolate nuclear-structure and kaon-multinucleon effects. Measurements of Mg, Al, Si, and S with CdZnTe detectors will broaden this study toward heavier nuclei. EXKALIBUR will establish a systematic experimental framework for testing low-energy strong interaction with strangeness and bound-state QED predictions across a broad range of kaonic atoms.
Pulse-shape discrimination with machine learning for CZT detectors at the DAFNE beam test facility
S. Manti, F. Artibani, L. Abbene, M. Bazzi, M. Bettelli, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, G. Gerardi, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, J. Marton, P. Moskal, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, O. Vazquez Doce, A. Zappettini, J. Zmeskal, C. Curceanu
abstract
Cadmium zinc telluride (CZT) detectors offer versatility, operational simplicity, and room-temperature X- and gamma-ray spectroscopy, making them attractive for collider applications, yet their use under high-flux conditions remains limited. Here, we present a preliminary feature-based pulse-shape analysis employing machine learning, on data acquired with a quasi-hemispherical CZT detector at the DAFNE beam test facility of the National Laboratory of Frascati of INFN. A 300-MeV electron beam impinging on a lead target produced characteristic Pb X-rays together with a broad background extending up to the electron-positron annihilation region. Physically motivated temporal and morphological features were extracted from the recorded waveforms and used to distinguish nominal photon-like pulses from anomalous events. An XGBoost classifier trained and validated on 10,000 labeled waveforms achieved an accuracy of approximately 97%, with most of its classification performance reached using only a few hundred labeled examples. The trained model was applied to more than 700,000 events, substantially reducing the spectral continuum and coincidence peaks, while preserving the characteristic Pb X-ray lines up to the 511-keV annihilation peak. These preliminary results demonstrate the potential of machine-learning-assisted pulse-shape discrimination for improving CZT spectroscopy in collider environments.
Kaonic copper and fluorine absolute yields measurement with a CZT-based detection system at DA?NE
F. Artibani, S. Manti, L. Abbene, A. Buttacavoli, M. Bettelli, G. Gerardi, F. Principato, A. Zappettini, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, M. Carminati, A. Clozza, F. Clozza, R. Del Grande, L. De Paolis, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, J. Marton, P. Moskal, F. Napolitano, H. Ohnishi, K. Piscicchia, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, O. Vazquez Doce, J. Zmeskal, C. Curceanu and A. Scordo
abstract
In this work, new measurements of absolute X-ray yields for several transitions in kaonic
copper and, for the first time, in kaonic fluorine are reported. The data were collected by
the SIDDHARTA-2 collaboration at the DAFNE collider using a novel room-temperature
Cadmium Zinc Telluride (CZT) detection system. Detection efficiencies were evaluated
through a dedicated Geant4 Monte Carlo simulation of the full experimental setup, enabling
the extraction of absolute yields per stopped kaon.
The measured yields exhibit a systematic dependence on the principal quantum number,
reflecting the interplay between radiative transitions, Auger de-excitation, and
strong-interaction-induced nuclear capture. In kaonic fluorine, a suppression of the 4->3
transition yield relative to higher-n transitions is observed, providing evidence for the onset
of strong-interaction effects already at the n = 4 level. From this behaviour, a conservative
lower limit on the corresponding strong-interaction width is derived.
These results provide new quantitative constraints for cascade models of exotic atoms and
extend experimental access to intermediate atomic levels where strong-interaction effects
are not directly observable via level shifts and widths. They also establish CZT-based
detection as a powerful and versatile approach for high-resolution X-ray spectroscopy of
kaonic atoms in collider environments.
QED precision studies in kaonic atoms with SIDDHARTA-2
F. Clozza, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, A. Clozza, R. Del Grande, L. De Paolis, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
Kaonic atoms, where a negatively charged kaon replaces an electron,
provide a unique system for precision studies of bound-state and strong-field
quantum electrodynamics (QED). The SIDDHARTA-2 experiment at the DAFNE
at INFN-LNF collider performs high-resolution X-ray spectroscopy of these systems
using Silicon Drift Detectors. The recent measurement on kaonic neon enables stringent
bound-state QED tests and a pathway towards a refined determination of the
charged kaon mass, while preliminary kaonic fluorine data demonstrate the potential
to probe strong-field QED effects. These results highlight the role of SIDDHARTA-2
in advancing high precision QED studies with hadronic atoms.
Precision test of bound-state QED at intermediate Z with kaonic neon
S. Manti, F. Sgaramella, L. Abbene, C. Amsler, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, R. Del Grande, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, P. Indelicato, M. Iwasaki, A. Khreptak, J. Marton, P. Moskal, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, J. Sommerfeldt, A. Spallone, K. Toho, L. Toscano, O. Vazquez Doce, J. Zmeskal and C. Curceanu
abstract
We report Dirac-Fock calculations of transition energies for kaonic neon. For the most intense line, the 7->6 transition, the calculated energy is 9450.28 eV, which includes a bound-state QED (BSQED) contribution of 12.66 eV. This is in excellent agreement with the recent SIDDHARTHA-2 measurement at DAFNE of 9450.23+-0.37(stat.)+-1.50(syst.) eV. With the QED contribution far exceeding experimental uncertainty, these results establish kaonic atoms as sensitive platforms for precision tests of BSQED in intermediate-Z systems.
Time-based Selection of Kaonic Atom X-ray Events with Quasi-Hemispherical CZT Detectors at the DAFNE collider
F. Artibani, L. Abbene, A. Buttacavoli, M. Bettelli, G. Gerardi, F. Principato, A. Zappettini, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, M. Carminati, A. Clozza, F. Clozza, R. Del Grande, L. De Paolis, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, H. Ohnishi, K. Piscicchia, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, L.G. Toscano, O. Vazquez Doce, J. Zmeskal, C. Curceanu and A. Scordo
abstract
This work presents the results of a time-based event selection for the search of X-ray signals from kaonic atom transitions using a quasi-hemispherical Cadmium-Zinc-Telluride (CZT) detector at the DAFNE collider. To mitigate the high background level in the measured X-ray spectra, a dedicated event selection strategy was developed, exploiting the precise timing correlation between e+e- collisions and detector signals. This approach enabled, for the first time, the observation of two characteristic X-ray transitions from kaonic aluminum atoms with a CZT detector. For the 5-4 transition at 50 keV, 362 +- 41 (stat.) +- 20 (sys.) signal events were observed over 1698 +- 197 (stat.) +- 25 (sys.) background events within +- 5sigma, with an energy resolution of 9.2% FWHM. For the 4-3 transition at 106 keV, 295 +- 50 (stat.) +- 20 (sys.) signal events were measured over 2939 +- 500 (stat.) +- 16 (sys.) background events, with an energy resolution of 6.6% FWHM. A background suppression of approximately 95% of the triggered data was achieved through this time-based selection. The demonstrated timing capability of the CZT detector proved highly effective in isolating time-correlated events within an 80ns window, setting an important benchmark for the application of compound semiconductors in timing-based X-ray spectroscopy. These results highlight the potential of CZT-based detection systems for future precision measurements in high-radiation environments, paving the way for compact, room-temperature X-ray and gamma-ray spectrometers in fundamental physics and related fields.
EXKALIBUR: Towards a Kaonic Atoms Periodic Table to Test Fundamental Interactions
S. Manti, A. Khreptak, J. Marton, P. Moskal, H. Ohnishi, K. Pischicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. Sirgh, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, L. Toscano, O. Vazquez Doce, M. Iwasaki, P. Indelicato, M. Iliescu, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, F. Clozza, A. Clozza, L. De Paolis, R. Del Grande, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Curceanu
abstract
Kaonic atoms, formed when a negatively charged kaon replaces an electron, provide a unique laboratory to test fundamental interactions at low energies. EXKALIBUR (EXtensive Kaonic Atoms research: from LIthium and Beryllium to URanium) is a program to perform systematic, high-precision X-ray spectroscopy of selected kaonic atoms across the periodic table at the DAFNE accelerator at the National Laboratory of Frascati. Here, we outline its detector-driven strategy: silicon drift detectors for 10-40 keV transitions in light targets (Li, Be, B, O), CdZnTe detectors for 40-300 keV lines in intermediate-Z systems (Mg, Al, Si, S), and a high-purity germanium detector for high-Z atoms (Se, Zr, Ta, Mo, W, Pb), complemented by VOXES, a high-resolution crystal spectrometer for sub eV studies. EXKALIBUR plans to (i) reduce the charged-kaon mass uncertainty below 10 keV, (ii) produce a database of nuclear shifts and widths to constrain multi-nucleon K--nucleus interactions models, and (iii) provide precision data for testing bound-state quantum electrodynamics in strong fields. We summarize the planned measurements and expected sensitivities within DAFNE luminosities.
High precision X-ray spectroscopy of kaonic neon
F. Sgaramella, D. Sirghi, K. Toho, F. Clozza, L. Abbene, C. Amsler, M. Bazzi, G. Borghi, D. Bosnar, A. M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, R. Del Grande, L. De Paolis, K. Dulski, L. Fabbietti, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, L. G. Toscano, M. Tuchler, O. Vazquez Doce, E. Widmann, J. Zmeskal, C. Curceanu
abstract
The high-precision kaonic neon X-ray transitions measurement performed by the SIDDHARTA-2 collaboration at the DAFNE collider is reported. Both the X-ray energies and yields for high-n transitions were measured, demonstrating the feasibility of sub-eV X-ray spectroscopy for kaonic atoms using low-Z gaseous targets. The measurement provides valuable insights into the de-excitation processes in kaonic atoms, providing new input data for the refinement of the corresponding theoretical models, and a framework for testing Quantum Electrodynamics in strange exotic atoms.
Kaonic Atoms with the SIDDHARTA-2 Experiment at DAFNE
F. Napolitano, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, M. Cargnelli, A. Clozza, F. Clozza, G. Deda, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, D. Sirghi, F. Sirghi, M. Skurzok, M. Silarski, A. Spallone, K. Toho, L.G. Toscano, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTA-2 experiment aiming at measuring for the first time the X-ray transitions in kaonic deuterium, has successfully completed its 2024 physics run at the DAFNE collider of the INFN Laboratori Nazionali di Frascati. This work presents an overview of the scientific and technical achievements of SIDDHARTA-2 so far, including the most precise measurement of kaonic helium-4 Lalpha transitions and yields in gas, the observation of the kaonic helium-4 M-series transitions, and the measurement of high-n transitions in kaonic carbon, oxygen, nitrogen, and aluminium. The results of these measurements are discussed in the context of the kaonic atoms physics program at DA?NE, including future prospects within the EXKALIBUR proposal.
First Stability Characterization for a CZT Detection System in an e+e- Collider Environment
L. Abbene, F. Artibani, M. Bettelli, A. Buttacavoli, F. Principato, A. Zappettini, M. Bazzi, G. Borghi, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, L. de Paolis, R. del Grande, K. Dulski, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedzwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, L. Toscano, M. Tuchler, O. Vazquez Doce, J. Zmeskal, C. Curceanu, A. Scordo
abstract
The SIDDHARTA-2 collaboration has developed a novel X-ray detection system based on cadmium-zinc-telluride (CZT, CdZnTe), marking the first application of this technology at the DAFNE electron-positron collider at INFN-LNF. This work aims to demonstrate the stability of the detectors' performance in terms of linearity and resolution over short and long periods, thereby establishing their suitability for precise spectroscopic measurements within a collider environment. A reference calibration spectrum is presented in association with findings from assessments of linearity and resolution stability. Additionally, this study introduces a validated model of the response function of the detector. The relative deviations from the nominal values for the source transitions, obtained by fitting the entire spectrum with a background function and the previously introduced response function, are reported. Finally, a comparison of the calibration performance with and without beams circulating in the collider's rings is presented. These promising results pave the way for applying CZT detectors in kaonic atom studies and, more generally, in particle and nuclear physics spectroscopy.
SIDDHARTA-2 apparatus for kaonic atoms research on the DAFNE collider
F. Sirghi, F. Sgaramella, L. Abbene, C. Amsler, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Carminati, M. Cargnelli, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, D. Sirghi, M. Skurzok, M. Silarski, A. Spallone, K. Toho, L. Toscano, M. Tüchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
SIDDHARTA-2 represents a state-of-the-art experiment designed to perform dedicated measurements of kaonic atoms, which are particular exotic atom configurations composed of a negatively charged kaon and a nucleus. Investigating these atoms provides an exceptional tool to comprehend the strong interactions in the non-perturbative regime involving strangeness. The experiment is installed at the DAFNE electron-positron collider, of the INFN National Laboratory of Frascati (INFN-LNF) in Italy, aiming to perform the first-ever measurement of the 2p->1s X-ray transitions in kaonic deuterium, a crucial step towards determining the isospin-dependent antikaon-nucleon scattering lengths. Based on the experience gained with the previous SIDDHARTA experiment, which performed the most precise measurement of the kaonic hydrogen 2p->1s X-ray transitions, the present apparatus has been upgraded with innovative Silicon Drift Detectors (SDDs), distributed around a cryogenic gaseous target placed in a vacuum chamber at a short distance above the interaction region of the collider. We present a comprehensive description of the SIDDHARTA-2 setup including the optimization of its various components during the commissioning phase of the collider.
A feasibility study of the measurement of kaonic lead X-rays at DAFNE for the precise determination of the charged kaon mass
D. Bosnar, L. Abbene, C. Amsler, F. Artibani, M. Bazzi, A. Buttacavoli, M. Carminati, M. Cargnelli, A. Clozza, F. Clozza, G. Deda, L. De Paolis, R. Del Grande, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, M. Makek S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, A. Scordo, F. Sgaramella, D. Sirghi, F. Sirghi, M. Skurzok, M. Silarski, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
An HPGe detector equipped with a transistor reset preamplifier and readout with a CAEN DT5781 fast pulse
digitizer was employed in the measurement of X-rays from kaonic lead at the DAFNE e+e- collider at the
Laboratori Nazionali di Frascati of INFN. A thin scintillator in front of a lead target was used to select kaons
impinging on it and to form the trigger for the HPGe detector. We present the results of the kaonic lead
feasibility measurement, where we show that the resolution of the HPGe detector in regular beam conditions
remains the same as that without the beam and that a satisfactory background reduction can be achieved.
This measurement serves as a test bed for future dedicated kaonic X-rays measurements for the more precise
determination of the charged kaon mass.
The SIDDHARTA-2 experiment for high precision kaonic atoms X-ray spectroscopy at DAFNE
F. Sgaramella, L. Abbene, C. Amsler, F. Artibani, M. Bazzi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
High precision X-ray spectroscopy of light kaonic atoms provides
valuable information on kaon-nucleus interaction at threshold, allowing to investigate
the strong interaction in the strangeness sector at the low-energy frontier. The
SIDDHARTA-2 experiment at the DAFNE collider of INFN-LNF is performing the
challenging measurement of the kaonic deuterium 2p->1 s transition which together
with the kaonic hydrogen measurement performed by SIDDHARTA, will allow to
extract the isospin-dependent antikaon-nucleon scattering lengths. To achieve this
goal, the optimization of the setup to maximize the signal over background ratio
is a crucial step. This paper presents the SIDDHARTA-2 experiment and its optimization
through the first observation of kaonic neon transitions. The excellent
electromagnetic background reduction factor (~10^4) paves the way not only to the
measurement of kaonic deuterium, but also to a new era of selected kaonic atom
measurements along the periodic table.
The Odyssey of kaonic atoms studies at the DAFNE collider: From DEAR to SIDDHARTA-2
F. Artibani, F. Clozza, M. Bazzi, C. Capoccia, A. Clozza, L. De Paolis, K. Dulski, C. Guaraldo, M. Iliescu, A. Khreptak, S. Manti, F. Napolitano, O. Vazquez Doce, A. Scordo, F. Sgaramella, F. Sirghi, A. Spallone, M. Cargnelli, J. Marton, M. Tüchler, J. Zmeskal, L. Abbene, A. Buttacavoli, F. Principato, D. Bosnar, I. Friščić, M. Bragadireanu, G. Borghi, M. Carminati, G. Deda, C. Fiorini, R. Del Grande, M. Iwasaki, P. Moskal, S. Niedźwiecki, M. Silarski, M. Skurzok, H. Ohnishi, K. Toho, D. Sirghi, K. Piscicchia, C.O. Curceanu
abstract
In this paper, an overview of kaonic atoms studies from the late 90s to nowadays at the DAFNE collider at INFN-LNF is presented. Experiments on kaonic atoms are an important tool to test and optimize phenomenological models on the low-energy strong interaction. Since its construction, the DAFNE collider has represented an ideal machine to perform kaonic atoms measurements, thanks to the unique beam of kaons coming from the Phi_s produced in the collider decays. The DEAR and SIDDHARTA experiments achieved the precise evaluation of the shift and width of the 2p -> 1s transition in kaonic hydrogen due to the strong interaction, and thus provided a measurement strictly linked to isospin-dependent antikaon-nucleon scattering lengths. To fully disentangle the iso-scalar and iso-vector scattering lengths, the measurement of kaonic deuterium is necessary as well. The SIDDHARTA-2 experiment is now taking data at the DAFNE collider with the aim to fulfill the need of this measurement, and therefore provide important information to the various phenomenological models on low-energy strong interactions with strangeness. The SIDDHARTA-2 Collaboration is also exploring the possibility to perform future kaonic atoms experiments, developing X-ray detector systems beyond the current stateof-art. These measurements are crucial for a deeper understanding of the kaon interactions with nuclei and for solving the kaon mass ''puzzle''.
First measurement of kaonic helium-4 M-series transitions
F. Sgaramella, D. Sirghi, L. Abbene, F. Artibani, M. Bazzi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, L. Fabbietti, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedzwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
In this paper we present the results of a new kaonic helium-4 measurement with a 1.37 g/l gaseous target by the SIDDHARTA-2 experiment at the DAFNE collider. We measured, for the first time, the energies and yields of three transitions belonging to the Mseries. Moreover, we improved by a factor about three, the statistical precision of the 2p level energy shift and width induced by the strong interaction, obtaining the most precise measurement for gaseous kaonic helium, and measured the yield of the L_alpha transition at the employed density, providing a new experimental input to investigate the density dependence of kaonic atoms transitions yield.
CdZnTe detectors tested at the DAFNE collider for future kaonic atoms measurements
A. Scordo, L. Abbene, F. Artibani, M. Bazzi, M. Bettelli, D. Bosnar, G. Borghi, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, G. Deda, R. Del Grande, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, Y. Sada, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, A. Zappettini, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTA-2 collaboration at the INFN Laboratories of Frascati (LNF) aims to perform groundbreaking measurements on kaonic atoms. In parallel and beyond the ongoing kaonic deuterium, presently running on the DAFNE collider at LNF, we plan to install additional detectors to perform further kaonic atoms' studies, taking advantage of the unique low energy and low momentum spread K- beam delivered by the at-rest decay of the phi meson. CdZnTe devices are ideal for detecting transitions toward both the upper and lower levels of intermediate-mass kaonic atoms, like kaonic carbon and aluminium, which have an important impact on the strangeness sector of nuclear physics. We present the results obtained in a set of preliminary tests conducted on DAFNE, in view of measurements foreseen in 2024, with the twofold aim to tune the timing window required to reject the extremely high electromagnetic background, and to quantify the readout electronics saturation effect due to the high rate, when placed close to the Interaction Region (IR). In the first test we used commercial devices and electronics, while for the second one both were customized at the IMEM-CNR of Parma and the University of Palermo. The results confirmed the possibility of finding and matching a proper timing window where to identify the signal events and proved better performances, in terms of energy resolution, of the custom system. In both cases, strong saturation effects were confirmed, accounting for a loss of almost 90% of the events, which will be overcome by a dedicated shielding structure foreseen for the final experimental setup.
Characterization of the SIDDHARTA-2 Setup via the Kaonic Helium Measurement
F. Sgaramella, A. Clozza, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedzwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, J. Zmeskal, C. Curceanu
abstract
The aim of the SIDDHARTA-2 experiment is to perform the first measurement ever of the width and shift induced by the strong interaction to the 2????->1????
energy transition of kaonic deuterium. This ambitious goal implies a challenging task due to the very low X-ray yield of kaonic deuterium, which is why an accurate and thorough characterization of the experimental apparatus is mandatory before starting the data-taking campaign. Helium-4 is an excellent candidate for this characterization since it exhibits a high yield in particular for the 3????->2????
transition, roughly 100 times greater than that of the kaonic deuterium. The ultimate goal of the work reported in this paper is to study the performances of the full experimental setup in view of the kaonic deuterium measurement. This is carried out by measuring the values of the shift and the width for the 3?????2????
energy transition of kaonic helium-4, induced by the strong interaction. The values obtained for these quantities, for a total integrated luminosity of ~31/pb, are epsilon_2????=2.0+-1.2(stat)+-1.5(syst)eV
and Gamma_2????=1.9+-5.7(stat)+-0.7(syst)eV. The results, compared to the value of the shift measured by the SIDDHARTA experiment epsilon_2????=0+-6(stat)+-2(syst)eV, show a net enhancement of the resolution of the apparatus, providing strong evidence of the potential to perform the challenging measurement of the kaonic deuterium.
Efficiency analysis and promising applications of silicon drift detectors
A. Khreptak, M. Skurzok
abstract
Silicon drift detectors (SDDs) stand as a groundbreaking technology with a diverse range of applications, particularly in the fields of physics and medical imaging. This paper provides an analysis of the performance of SDDs as detectors for X-ray radiation measurement, shedding light on their exceptional capabilities and potential in medical imaging. Compared to conventional detectors, SDDs have several notable advantages. Their high efficiency in capturing X-rays allows them to provide outstanding sensitivity and accuracy in detecting even low-energy X-rays. In addition, SDDs exhibit significantly low electronic-noise levels, contributing to better signal-to-noise ratio and better data quality. Furthermore, their high resolution enables exact spatial localization of radiation sources, which is essential for accurate diagnosis. This research is devoted to the evaluation of efficiency and potential application of SDDs in X-ray spectroscopy, with particular emphasis on their application in medical imaging. We focus on evaluating the performance characteristics of SDDs, such as their linearity, stability and sensitivity in detecting X-rays. The aim is to highlight the suitability of SDDs for a wide range of applications.
The SIDDHARTA-2 Veto-2 system for X-ray spectroscopy of kaonic atoms at DAFNE
M. Tüchler, C. Amsler, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton1, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, O. Vazquez Doce, E. Widmann, C. Yoshida, J. Zmeskal and C. Curceanu
abstract
The Veto-2 is a fundamental component of a multiple-stage veto system for the SIDDHARTA-2 experiment installed at the DAFNE collider at INFN-LNF in Italy. It was developed to improve the signal-to-background ratio for the challenging measurement of X-ray transitions to the fundamental level in kaonic deuterium. Its purpose is the suppression of hadronic background in the form of Minimum Ionizing Particles by using the topological correlation between signals in the X-ray and Veto-2 detectors. The Veto-2 system consists of a barrel of plastic scintillators read out by Silicon Photomultipliers. The system performed its first successful test run within the apparatus with a helium-4 target in 2022. The efficiency of the Veto-2 was determined and found to be 0.62 +- 0.01. The Veto-2 improved the signal-to-background ratio for the kaonic helium-4 L_alpha measurement by about 16%, which is crucial due to the low expected X-ray yield of kaonic deuterium.
Kaonic atoms at the DAFNE collider: a strangeness adventure
C. Curceanu, L. Abbene, C. Amsler, M. Bazzi, M. Bettelli, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedzwiecki, H. Ohnishi, K. Piscicchia, F. Principato, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, O. Vazquez Doce, C. Yoshida, A. Zappettini, J. Zmeskal
abstract
Kaonic atoms are an extremely efficient tool to investigate the strong interaction at the low energy Frontier, since they provide direct access to the K?N interaction at threshold, eliminating the necessity for extrapolation, unlike in the case of scattering experiments. During the 1970s and 1980s, extensive studies were performed on kaonic atoms spanning across a broad spectrum of elements in the periodic table, ranging from lithium to uranium. These measurements provided inputs and constraints for the theoretical description of the antikaon-nuclei interaction potential. Nevertheless, the existing data suffer from significant experimental uncertainties, and numerous measurements have been found to be inconsistent with more recent measurements that utilize advanced detector technology. Furthermore, there remain numerous transitions of kaonic atoms that have yet to be measured. For these reasons, a new era of kaonic atoms studies is mandatory. The DA?NE electron-positron collider at the INFN Laboratory of Frascati (INFN-LNF) stands out as a unique source of low-energy kaons, having been utilized by Collaborations such as DEAR, SIDDHARTA, and AMADEUS for groundbreaking measurements of kaonic atoms and kaon-nuclei interactions. Presently, the SIDDHARTA-2 experiment is installed at DA?NE, aiming to perform the first-ever measurement of the 2p ? 1s x-ray transition in kaonic deuterium, a crucial step towards determining the isospin-dependent antikaon-nucleon scattering lengths. Based on the experience gained with the SIDDHARTA experiment, which performed the most precise measurement of the kaonic hydrogen 2p ? 1s x-ray transition, the SIDDHARTA-2 setup is now fully equipped for the challenging kaonic deuterium measurement. In this paper, we present a comprehensive description of the SIDDHARTA-2 setup and of the first kaonic atoms measurements performed during the commissioning phase of the DA?NE collider. We also outline a proposal for future measurements of kaonic atoms at DA?NE beyond SIDDHARTA-2, which is intended to stimulate discussions within the broad scientific community performing research, directly or indirectly, related to this field.
Potentialities of CdZnTe Quasi-Hemispherical Detectors for Hard X-ray Spectroscopy of Kaonic Atoms at the DAFNE Collider
L. Abbene, A. Buttacavoli, F. Principato, G. Gerardi, M. Bettelli, A. Zappettini, M. Bazzi, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, L. De Paolis, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedzwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal, A. Scordo, C. Curceanu
abstract
Kaonic atom X-ray spectroscopy is a consolidated technique for investigations on the physics of strong kaon?nucleus/nucleon interaction. Several experiments have been conducted regarding the measurement of soft X-ray emission (<20 keV) from light kaonic atoms (hydrogen, deuterium, and helium). Currently, there have been new research activities within the framework of the SIDDHARTA-2 experiment and EXCALIBUR proposal focusing on performing precise and accurate measurements of hard X-rays (>20 keV) from intermediate kaonic atoms (carbon, aluminum, and sulfur). In this context, we investigated cadmium?zinc?telluride (CdZnTe or CZT) detectors, which have recently demonstrated high-resolution capabilities for hard X-ray and gamma-ray detection. A demonstrator prototype based on a new cadmium?zinc?telluride quasi-hemispherical detector and custom digital pulse processing electronics was developed. The detector covered a detection area of 1 cm2 with a single readout channel and interesting room-temperature performance with energy resolution of 4.4% (2.6 keV), 3% (3.7 keV), and 1.4% (9.3 keV) FWHM at 59.5, 122.1, and 662 keV, respectively. The results from X-ray measurements at the DAFNE collider at the INFN National Laboratories of Frascati (Italy) are also presented with particular attention to the effects and rejection of electromagnetic and hadronic background.
The KAMEO proposal: Investigation of the E2 nuclear resonance effects in kaonic atoms
L. De Paolis on behalf of M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, C. Fiorini, I. Frišči`c, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Nied`zwiecki, O. Ohnishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, S. Wycech, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
The E2 nuclear resonance effect is a phenomenon that occurs whenthe energy of an atomic de-excitation state closely matches that of a nuclear excita-tion state, resulting in the attenuation of certain atomic X-ray lines in the resonantisotope target. The study of this effect in kaonic atoms can provide important insightinto the mechanisms of the strong kaon-nucleus interaction. In 1975, Goldfrey, Lum,and Wiegand at Lawrence Berkeley Laboratory observed the effect in9842Mo, but theydid not have enough data to reach a conclusive result. The E2 nuclear resonanceeffect is expected to occur in four kaonic molybdenum isotopes (9442Mo,9642Mo,9842Mo,and10042Mo) with similar energy values. The KAMEO (Kaonic Atoms MeasuringNuclear Resonance Effects Observables) proposal plans to study this effect in theseisotopes at the DA?NE ? factory during the SIDDHARTA-2 experiment. KAMEOwill use four solid strip targets, each enriched with a different molybdenum isotope,and expose them to negatively charged kaons produced by ? meson decays. TheX-ray transition measurements will be performed using a high-purity germaniumdetector, and an additional solid strip target of non-resonant9242Mo isotope will beexposed and used as a reference for standard non-resonant transitions.
New opportunities for kaonic atoms measurements from CdZnTe detectors
L. Abbene, M. Bettelli, A. Buttacavoli, F. Principato, A. Zappettini, C. Amsler, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal, A. Scordo and C. Curceanu
abstract
We present the tests performed by the SIDDHARTA-2 collaboration at the DAFNE collider with
a quasi-hemispherical CdZnTe detector. The very good room-temperature energy resolution and efficiency
in a wide energy range show that this detector technology is ideal for studying radiative transitions in
intermediate and heavy mass kaonic atoms. The CdZnTe detector was installed for the first time in an
accelerator environment to perform tests on the background rejection capabilities, which were achieved by
exploiting the SIDDHARTA-2 Luminosity Monitor. A spectrum with an 241Am source has been acquired,
with beams circulating in the main rings, and peak resolutions of 6% at 60 keV and of 2.2% at 511 keV
have been achieved. The background suppression factor, which turned out to be of the order of ~10^5?6,
opens the possibility to plan for future kaonic atom measurements with CdZnTe detectors.
Measurements of high-n transitions in intermediate mass kaonic atoms by SIDDHARTA-2 at DAFNE
F. Sgaramella, M. Tuchler, C. Amsler, M. Bazzi, D. Bosnar, A. M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, O. Vazquez Doce, J. Zmeskal, E. Widmann, C. Yoshida, C. Curceanu
abstract
The SIDDHARTA-2 experiment installed at the DAFNE collider of INFN-LNF performed, for the first time,
measurements of high-n transitions in intermediate mass kaonic atoms during the data taking campaigns of 2021 and
2022. Kaonic carbon, oxygen, nitrogen and aluminium transitions, which occur in the setup materials, were measured
by using the kaons stopped in the gaseous helium target cell with aluminium frames and Kaptonwalls, and are reported in
this paper. These new kaonic atoms measurements add valuable input to the kaonic atoms transitions data base, which is
used as a reference for theories and models of the low-energy strong interaction between antikaon and nuclei. Moreover,
these results pave the way for future dedicated kaonic atoms measurements through the whole periodic table and to a new
era for the antikaon-nuclei studies at low energy.
New measurements of kaonic helium-4 L-series X-rays yields in gas with the SIDDHARTINO setup
D. L. Sirghi, H. Shi, C. Guaraldo, F. Sgaramella, C. Amsler, M. Bazzi, D. Bosnar, A. M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, M. Iliescu, M. Iwasaki, J. Marton, M.. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Yoshida, C. Curceanu
abstract
The L-series X-rays transitions of the kaonic helium-4 exotic atom were measured by SIDDHARTINO,
the reduced configuration of the SIDDHARTA-2 experiment, at the DANE collider of INFN-LNF, with
gaseous 4He targets at densities of 1.90 g/l and 0.82 g/l, corresponding to 1.5% and 0.66%, respectively, of
the liquid helium-4 density. The absolute yields for the L? transition are determined to be 0.15 ?0.03 and
0.12 ?0.03, for the two target densities. The yields for the L? and L? transitions are presented relatively
to that of the L? transition. These results are compatible with the yields measured by the SIDDHARTA
experiment at the densities of 1.65 g/l and 2.15 g/l and contribute to refine the cascade models describing
the de-excitation of kaonic atoms as function of density.
? 2022 Elsevier B.V. All rights reserved.
First Tests of the Full SIDDHARTA-2 Experimental Apparatus with a 4He Gaseous Target
A. Scordo, C. Amsler, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, P. King, P. Levi Sandri, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, F. Sgaramella, H. Shi, M. Silarski, D.L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
In this paper, we present the first tests performed after the full installation of the SIDDHARTA-2 experimental apparatus on the interaction region of the DA?NE collider at the INFN National Laboratories of Frascati. Before starting the first measurement of the kaonic deuterium 2p->1s transition, an accurate evaluation of the background rejection was required, mainly achieved with the kaon trigger system. This run, performed in the period 04-26/05/2022 with a 4He gaseous target, confirmed the 105 order of magnitude of the rejection factor obtained with the reduced version of the setup and different machine conditions in 2021. This important outcome motivated the filling of the target cell with deuterium and the start of the measurement campaign of the kaonic deuterium 2p->1s transition.
Kaonic Atoms at the DAFNE Collider with the SIDDHARTA-2 Experiment
F. Napolitano, F. Sgaramella, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedźwiecki, K. Piscicchia, A. Scordo, H. Shi, D. Sirghi, F. Sirghi, M. Silarski, M. Skurzok, A. Spallone, M. Tüchler, J. Zmeskal, C. Curceanu
abstract
Kaonic atoms are a unique tool to explore quantum chromodynamics in the strangeness sector at low energy, with implications reaching neutron stars and dark matter. Precision X-ray spectroscopy can fully unlock the at-threshold isospin dependent antikaon-nucleon scattering lengths, via the atomic transitions to the fundamental level. While the SIDDHARTA experiment at the INFN-LNF DAFNE collider successfully measured kaonic hydrogen, its successor SIDDHARTA-2 is starting now its data taking campaign aiming to finally fully disentangle the isoscalar and isovector scattering lengths via the measurement of kaonic deuterium. An overview of the first experimental results from a preparatory run for the SIDDAHARTA-2 experiment is presented.
The SIDDHARTA-2 calibration method for high precision kaonic atoms X-ray spectroscopy measurements
F. Sgaramella, M. Miliucci, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTA-2 experiment at the DAFNE collider aims to perform the first kaonic deuterium X-ray transitions to the fundamental level measurement, with a systematic error at the level of a few eV. To achieve this challenging goal the experimental apparatus is equipped with 384 Silicon Drift Detectors (SDDs) distributed around its cryogenic gaseous target. The SDDs developed by the SIDDHARTA-2 collaboration are suitable for high precision kaonic atoms spectroscopy, thanks to their high energy and time resolutions combined with their radiation hardness. The energy response of each detector must be calibrated and monitored to keep the systematic error, due to processes such as gain fluctuations, at the level of 2-3 eV. This paper presents the SIDDHARTA-2 calibration method which was optimized during the preliminary phase of the experiment in the real background conditions of the DAFNE collider, which is a fundamental tool to guarantee the high precision spectroscopic performances of the system over long periods of data taking, as that required for the kaonic deuterium measurement.
Towards the first kaonic deuterium measurement with the SIDDHARTA-2 experiment at DAFNE
M. Miliucci, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, J. Zmeskal
abstract
The SIDDHARTA-2 experiment is going to perform the longawaited
high precision X-ray measurement of kaonic deuterium, obtaining for the
first time the values of the shift and the width induced by the strong interaction
on the fundamental level. By combining this unprecedented result with the
analogous kaonic hydrogen measurement performed by the SIDDHARTA experiment,
it will be possible to extract the isospin-dependent antikaon-nucleon scattering
lengths, providing direct information on the Quantum Chromodynamics (QCD)
in the non-perturbative Chromodynamics (QCD) in the non-perturbative regime
in the strangeness sector. This paper describes the SIDDHARTA-2 experiment,
presently installed at the DA?NE collider of Istituto Nazionale di Fisica Nucleare -
Laboratori Nazionali di Frascati, and the results obtained during the kaonic helium
run, preparatory for the kaonic deuterium data taking campaign planned for 2022.
Large area silicon drift detectors system for high precision timed x-ray spectroscopy
M. Miliucci, M. Iliescu, F. Sgaramella, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce and J. Zmeskal
abstract
The current work presents the optimization of large area silicon drift detectors developed by the SIDDHARTA-2 collaboration for high precision x-ray measurements of light exotic atom transitions. Two different radiation sources were employed in the study: an x-ray tube, for investigating the energy resolution and the charge collection efficiency of the device in the range 4000 eV-13000 eV, and a beta-90Sr radioactive source for measuring the timing response, thus qualifying the charge drift parameters inside the semiconductor. The study reports the spectroscopic response optimization, together with the tuning of the electron dynamics for the given Silicon technology, by adjusting the applied electric field and the working temperature, which allow a good control of the device's performances for high precision, timed x-ray spectroscopy applications.
A new kaonic helium measurement in gas by SIDDHARTINO at the DAFNE collider
D. Sirghi, F. Sirghi, F. Sgaramella, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S Niedźwiecki, K. Piscicchia, A. Scordo, H. Shi, M. Skurzok, M. Silarski, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTINO experiment at the DAFNE Collider of INFN-LNF, the pilot run for the SIDDHARTA-2 experiment which aims to perform the measurement of kaonic deuterium transitions to the fundamental level, has successfully been concluded. The paper reports the main results of this run, including the optimization of various components of the apparatus, among which the degrader needed to maximize the fraction of kaons stopped inside the target, through measurements of kaonic helium transitions to the 2p level. The obtained shift and width values are epsilon_2p = E_exp-E_e.m = 0.2 pm 2.5(stat) pm 2(syst) eV and Gamma_2p = 8 pm 10 eV (stat), respectively. This new measuremnt of the shift, in particular, represents the most precise one for a gaseous target and is expected to contribute to a better understanding of the kaon-nuclei interaction at low energy.
Silicon Drift Detectors' Spectroscopic Response during the SIDDHARTA-2 Kaonic Helium Run at the DAFNE Collider
M. Miliucci, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
A large-area silicon drift detectors (SDDs) system has been developed by the SIDDHARTA-2 collaboration for high precision light kaonic atom X-ray spectroscopy at the DAFNE collider of Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali di Frascati. The SDDs' geometry and electric field configuration, combined with their read-out electronics, make these devices suitable for performing high precision light kaonic atom spectroscopy measurements in the background of the DA phi NE collider. This work presents the spectroscopic response of the SDDs system during the first exotic atoms run of SIDDHARTA-2 with kaonic helium, a preliminary to the kaonic deuterium data taking campaign. The SIDDHARTA-2 spectroscopic system has good energy resolution and a 2 mu s timing window which rejects the asynchronous events, scaling the background by a factor of 10-5. The results obtained for the first exotic atoms run of SIDDHARTA-2 prove this system to be ready to perform the challenging kaonic deuterium measurement.
Kaonic Atoms Measurements at DAFNE: SIDDHARTA-2 and Future Perspectives
C. Curceanu,, M. Miliucci, A. Scordo, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
High precision light kaonic atoms X-ray spectroscopy is a unique tool for performing experiments equivalent to scattering at vanishing relative energies, to determine the antikaon-nucleus interaction at threshold without the need of extrapolation to zero energy. The SIDDHARTA-2 collaboration is going to perform the first measurement of kaonic deuterium transitions to the fundamental level, which is mandatory to extract the isospin dependent antikaon-nucleon scattering lengths. The SIDDHARTA-2 experiment is presently installed on the DA Phi NE collider of INFN-LNF. The preliminary results obtained during the machine commissioning phase in preparation for the kaonic deuterium data taking campaign, together with future perspectives for extreme precision kaonic atoms studies at DA Phi NE are presented.
Low energy kaon-nuclei interaction at DAFNE: The SIDDHARTA-2 experiment
M. Miliucci, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
Light kaonic atoms spectroscopy is a unique tool for the investigation of the low-energy quantum chromodynamics (QCD) in the strangeness sector. The precise measurements of the X-ray emission from light kaonic atoms provide information on the kaon-nucleus interaction at the threshold without the need for an extrapolation as in the case of scattering experiments. In 2009, the SIDDHARTA Collaboration performed the most precise measurement of kaonic hydrogen (K - H) X-ray transition to the fundamental level. Nowadays, the SIDDHARTA-2 Collaboration is ready to perform the more challenging measurement of kaonic deuterium (K - d) 2p -> 1s transition. To achieve this unprecedented result, which is fundamental to extract the isospin-dependent antikaon-nucleon scattering lengths, an upgraded experimental apparatus with respect to the SIDDHARTA one was realized. This paper presents an overview of the SIDDHARTA-2 setup installed on the DAFNE collider of LNF-INFN and the first results obtained during the machine optimization phase, in preparation for the kaonic deuterium data taking campaign planned in 20212022.
Silicon Drift Detectors system for high precision light kaonic atoms spectroscopy
M. Miliucci, A. Scordo, D. Sirghi, A. Amirkhani, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, F. Sgaramella, H. Shi, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
A large area Silicon Drift Detectors (SDDs) system and its readout electronics have been developed by the SIDDHARTA-2 Collaboration, aiming to perform high precision light kaonic atoms X-ray spectroscopy for the investigation of the ?-N strong interaction in the low-energy QCD regime. To perform these measurements, a linear energy response and a good energy resolution are mandatory requirements for the system, to be preserved along the whole DAQ (analog and digital) chain; such task is made even harder in the experimental environment of particles colliders, where the high background due to ionizing particles and radiation is present. The energy response of the SDDs system has been characterized with the beam-originating background generated during the commissioning phase of the DAFNE electron-positron collider (INFN-LNF) in early 2020. The data analysis has been optimized to describe the system's response and the background. The calibration procedure demonstrates that, despite the high and variable background of the collider, the energy response of the system is linear at the level of few eV (?E/E <10e-3), with an energy resolution of 157.8?0.3(+0.2)(-0.2)eV for the Fe Kalpha line.
Characterization of the SIDDHARTA-2 luminosity monitor
M. Skurzok, A. Scordo, S. Niedzwiecki, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, K. Piscicchia, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
A luminosity monitor, based on plastic scintillator detectors, has been developed for the SIDDHARTA-2 experiment aiming to perform high precision measurements of kaonic atoms and was installed in 2020 on the DAFNE e+e- collider at LNF (Laboratori Nazionali di Frascati, INFN). The main goal of this system is to provide the~instantaneous and integrated luminosity of the DAFNE facility by measuring the rate of K+K- correlated pairs emitted by the Phi meson decay. This task requires an accurate timing of the DAQ signals, as well as timing resolution below 1ns, in order to disentangle the K+- signals from the background minimum ionizing particles (MIPs) produced during the e+e- collisions at DAFNE. In this paper the luminosity monitor concept as well as its laboratory characterization and the first results inside DAFNE are presented.
Kaonic Atoms to Investigate Global Symmetry Breaking
C. Curceanu, C. Guaraldo, D. Sirghi, A. Amirkhani, A. Baniahmad , M. Bazzi, G. Bellotti, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, L. De Paolis, R. Del Grande, C. Fiorini, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedzwiecki, S. Okada, K. Piscicchia, A. Scordo, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, M. Tuchler, G. Utica, O. Vazquez Doce, J. Zmeskal
abstract
Kaonic atoms measure the antikaon-nucleus interaction at almost zero relative energy, allowing one to determine basic low-energy quantum chromodynamics (QCD) quantities, namely, the antikaon-nucleon (KN) scattering lengths. The latter are important for extracting the sigma terms which are built on the symmetry breaking part of the Hamiltonian, thereby providing a measure of chiral and SU(3) symmetries breaking. After discussing the sigma terms and their relations to the kaonic atoms, we describe the most precise measurement in the literature of kaonic hydrogen, performed at LNF-INFN by the SIDDHARTA experiment. Kaonic deuterium is still to be measured, and two experiments are planned. The first, SIDDHARTA-2 at LNF-INFN was installed on DAFNE in spring 2019 and will collect data in 2020. The second, E57 at J-PARC, will become operative in 2021.
Revisiting the Charged Kaon Mass
D. Bosnar, M. Bazzi, M. Cargnelli, A. Clozza, C. Curceanu, R. Del Grande, C. Guaraldo, M. Iliescu, M. Makek, J. Marton, M. Miliucci, L. De Paolis, K. Piscicchia, A. Scordo, D.L. Sirghi, F. Sirghi, M. Skurzok, M. Tüchler, J. Zmeskal, P. Žugec
abstract
The precision of the charged kaon mass is an order of magnitude worse than the precision of the charged pion mass mainly due to two inconsistent measurements. We plan to improve this precision by determining the charged kaon mass with the requested accuracy in the measurements of X-ray transitions in kaonic atoms of selected solid targets with the HPGe detector at DAFNE in Laboratori Nazionali di Frascati, Italy. The measurements will be performed in parallel with SIDDHARTA-2 measurements of X-ray transitions in gaseous targets. The status of the preparation of the measurements will be presented.
Kaonic Deuterium Measurement with SIDDHARTA-2 on DAFNE
C. Curceanu, A. Amirkhani, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedźwiecki, S. Okada, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D.L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, M. Tüchler, O. Vazquez Doce, E. Widmann, J. Zmeskal
abstract
The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA Collaboration at the DAFNE electron-positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise Silicon-Drift X-ray detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA.
The modern era of light kaonic atom experiments
C. Curceanu, C. Guaraldo, M. Iliescu, M. Cargnelli, R. Hayano, J. Marton, J. Zmeskal, T. Ishiwatari, M. Iwasaki, S. Okada, D. L. Sirghi, and H. Tatsuno
abstract
This review covers the modern era of experimental kaonic atom studies, encompassing 20 years of activity, defined by breakthroughs in technological developments which allowed performing a series of long-awaited precision measurements. Kaonic atoms are atomic systems where an electron is replaced by a negatively charged kaon, containing the strange quark, which interacts in the lowest orbits with the nucleus also by the strong interaction. As a result, their study offers the unique opportunity to perform experiments equivalent to scattering at vanishing relative energy. This allows one to study the strong interaction between the antikaon and the nucleon or the nucleus ?at threshold,? namely, at zero relative energy, without the need of ad hoc extrapolation to zero energy, as in scattering experiments. The fast progress achieved in performing precision light kaonic atom experiments, which also solved long-pending inconsistencies with theoretical calculations generated by old measurements, relies on the development of novel cryogenic targets, x-ray detectors, and the availability of pure and intense charged kaon beams, which propelled an unprecedented progress in the field. Future experiments, based on new undergoing technological developments, will further boost the kaonic atom studies, thus fostering a deeper understanding of the low-energy strong interaction extended to the second family of quarks.
X-ray Detectors for Kaonic Atoms Research at DAFNE
C. Curceanu, A. Amirkhani, A. Baniahmad , M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, A. Clozza, R. Del Grande, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci , P. Moskal, S. Niedźwiecki, S. Okada, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann and J. Zmeskal
abstract
This article presents the kaonic atom studies performed at the INFN National Laboratory of Frascati (Laboratori Nazionali di Frascati dell'INFN, LNF-INFN) since the opening of this field of research at the DAFNE collider in early 2000. Significant achievements have been obtained by the DAFNE Exotic Atom Research (DEAR) and Silicon Drift Detector for Hadronic Atom Research by Timing Applications (SIDDHARTA) experiments on kaonic hydrogen, which have required the development of novel X-ray detectors. The 2019 installation of the new SIDDHARTA-2 experiment to measure kaonic deuterium for the first time has been made possible by further technological advances in X-ray detection
Low-Energy Kaon-Nuclei Interaction studies at the DAFNE Collider: a Strangeness Odyssey
F. Artibani, F. Clozza, L. Abbene, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, L. G. Toscano, M. Tüchler, J. Zmeskal and C. Curceanu
abstract
Kaonic atoms provide important observables for the study of the low-energy strong interactions with strangeness. Following SIDDHARTA?s kaonic hydrogen measurement, the SIDDHARTA-2 collaboration is performing the kaonic deuterium measurement, which will significantly enhance our understanding of kaon-nucleon interactions. Alongside this groundbreaking goal, the collaboration has provided other important measurements of kaonic atom transitions, which are significant not only for understanding low-energy strong interactions but also for studies in Quantum Electrodynamics. The experiment is also testing state-of-the-art X-ray detectors, paving the way for new technologies and future measurements of kaonic atoms with heavier nuclei.
Tests of New CZT detectors at DAFNE collider for Kaonic Atoms Measurements
F. Artibani, L. Abbene, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. L. Sirghi, F. C. Sirghi, M. Skurzok, A. Spallone, K. Toho, L.G. Toscano, M. Tuchler, J. Zmeskal and C. Curceanu
abstract
Kaonic atom spectroscopy provides key observables for investigating low-energy strong interactions in strange systems. In this paper, we present an overview of the SIDDHARTA-2 collaboration's activities in the field of kaonic atoms, with a particular focus on the development of a new Cadmium-Zinc-Telluride (CZT) detector system for the study of intermediate-mass kaonic atoms.
This novel detection system, applied for the first time in fundamental physics research at a collider, is designed to extend the energy range accessible in kaonic atom spectroscopy. We report on the characteristics of the detector and the results of test measurements conducted at the DAFNE collider between 2022 and 2024.The tests demonstrated that the detector's energy resolution, efficient background rejection, and good timing performance make it ideal for performing kaonic atom measurements.
The ultimate goal of these developments is to refine our understanding of kaon-multinucleon low-energy strong interactions by providing high-precision measurements of intermediate-mass kaonic atoms.
New Opportunities in Kaonic Atoms Spectroscopy With Novel CZT Detector
F. Artibani, L. Abbene, M. Bettelli, A. Buttacavoli, F. Principato, A. Zappettini, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, R. Del Grande, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, F. Sgaramella, D. L. Sirghi, F. Sirghi, M. Skurzok, M. Silarski, A. Spallone, K. Toho, L. Toscano, M. Tuchler, J. Zmeskal, C. Curceanu, A. Scordo
abstract
Kaonic atoms spectroscopy provides important observables for low-energy strong interactions in strange systems studies. In this paper, an overview of the SIDDHARTA-2 activities in kaonic atoms field is presented. Particular attention is given to the development of the new cadmium-zinc-telluride detection systems to measure intermediate-mass kaonic atoms. The characteristics of the detector, the results of the two first test measurements in DAFNE, and some of the physics goals are presented.
Kaonic atoms studies with SIDDHARTA-2 at DAFNE
K. Toho, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, F. Clozza, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, L. Toscano, M. Tuchler, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTA-2 experiment advances the study of kaonic atoms, focusing on kaonic deuterium
and other kaonic atoms, such as neon, to explore low-energy Quantum Chromodynamics (QCD). Utilizing
Silicon Drift Detectors and sophisticated veto systems, the experiment conducts high-precision X-ray
spectroscopy to measure strong interaction-induced shifts and broadenings of atomic energy levels. This
enables investigations of both electromagnetic and non-perturbative QCD effects, with high-n transitions
facilitating precision tests of Quantum Electrodynamics (QED) and lower-level transitions providing
insights into antikaon-nuclei strong interaction. Preliminary observation
A new measurement of the kaonic helium L-lineswith SIDDHARTA-2 at DAFNE
F. Clozza, L. Abbene, F. Artibani, M. Bazzi, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, F. Principato, A. Scordo, F. Sgaramella, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, J. Zmeskal, C. Curceanu
abstract
The ultimate goal of the SIDDHARTA-2 experiment at the LNF-INFN is to perform the first ever
measurement, via X-ray spectroscopy, of the width and shift induced by the strong interaction to the
2p -> 1s energy transition of kaonic deuterium. Such a measurement has not been performed yet due
to its high difficulty level; in fact, this transition exhibits an extremely low X-ray yield. For this reason,
before starting the kaonic deuterium data taking campaign, an accurate and thorough characterisation
of the experimental apparatus is of primary importance to gauge its performance. To finalize such a task
the best candidate is Helium-4, since the 3d ->2p transition of kaonic helium-4 exhibits a much higher
yield of X-rays. This work reports the results of the characterisation of the SIDDHARTA-2 apparatus in
preparation for the kaonic deuterium measurement. This is done by measuring the shift and width for
the 3d ? 2p transition of kaonic helium-4. The measured values are epsilon_2p = 2.0 pm 1.2(stat) pm 1.5(syst) eV
and Gamma_2p = 1.9 pm 5.7(stat) pm 0.7(syst) eV. The result shows a net enhancement of the performance
of the apparatus when compared to the previous measurement done by the SIDDHARTA experiment
epsilon_2p = 0 pm 6(stat) pm 2(syst) eV, thus providing strong evidence of the potential to perform the kaonic
deuterium measurement.
PANTHEON: Towards high-precision tests of the Pauli Exclusion Principle in Nuclear Reaction as a Testbed of Theories Beyond the Standard Model
C. Curceanu, F. Napolitano, M. Bazzi, I. Bolognino, N. Bortolotti, A. Clozza, L. De Paolis, M. Iliescu, S. Manti, A. Marciano, P. Moskal, H. Onishi, K. Piscicchia, A. Scordo, F. Sgaramella, D. L. Sirghi, F. C. Sirghi, M. Skurzok, A. W. Thomas
abstract
The PANTHEON project aims to test the Pauli Exclusion Principle (PEP) in Nuclear Reactions by searching for nuclear transitions prohibited by PEP in processes respecting the Messiah-Greenberg super-selection rule. The project aims to use the proton beam from the 3.5 MV Singletron accelerator of the Bellotti facility located at the Gran Sasso underground Laboratory, to perform a measurement based on a test setup able to disentangle protons coming from PEP prohibited processes. The goal is to prepare a dedicated setup for future measurements to improve by orders of magnitude the limit on PEP violation established in previous studies and
challenge theories beyond the Standard Model at a precision level presently unattained.
Kaonic helium-4 L-series yield measurement at 2.25 g/l density by SIDDHARTA-2 at DAFNE
F. Sgaramella, M. Bazzi, A. Clozza, C. Curceanu, L. De Paolis, K. Dulski, C. Guaraldo, M. Iliescu, A. Khreptak, S. Manti, F. Napolitano, A. Scordo, F. Sirghi, A. Spallone, M. Miliucci, F. Artibani, F. Clozza, M. Cargnelli, J. Marton, M. Tüchler, J. Zmeskal, L. Abbene, A. Buttacavoli, F. Principato, D. Bosnar, I. Friščić, M. Bragadireanu, G. Borghi, M. Carminati, G. Deda, C. Fiorini, R. Del Grande, M. Iwasaki, P. Moskal, S. Niedźwiecki, M. Silarski, M. Skurzok, H. Ohnishi, K. Toho, C. Yoshida, D. Sirghi, K. Piscicchia
abstract
This article presents the results of the kaonic helium-4 measurement conducted by the SIDDHARTA-2 experiment, aiming to provide crucial insights into the low-energy strong interaction in the strangeness sector. High-precision X-ray spectroscopy is used to examine the interaction between negatively charged kaons and nuclei in atomic systems. The SIDDHARTA-2setup was optimized through the kaonic helium-4 measurement in preparation for the challenging kaonic deuterium measurement. The kaonic helium-4 measurement at a new density of 2.25 g/l is reported, providing the absolute and relative yields for the L-series transitions, which are essential data for understanding kaonic atom cascade processes.
The measurement of the E2 nuclear resonance effects in kaonic atoms at DA?NE: The KAMEO proposal
L. De Paolis, L. Abbene, M. Bazzi, M. Bettelli, G. Borghi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, J. Obertova, O. Ohnishi, K. Piscicchia, F. Principato, Y. Sada, A. Scordo, F. Sgaramella, M. Silarski, D.L. Sirghi, F. Sirghi, M. Skurzok, S. Wycech, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, A. Zappettini, J. Zmeskal, C. Curceanu
abstract
KAMEO (Kaonic Atoms Measuring Nuclear Resonance Effects Ob-servables) is a proposal for an experiment aiming to perform the first consistent measurement of the E2 nuclear resonance effects in kaonic molybdenum A=94,96,98,100 isotopes. The E2 nuclear resonance mixes atomic states, due to the electrical quadrupole excitation of nuclear rotational states. It occurs in atoms having the energy of a nuclear excitation state closely matching an atomic de-excitation state energy, and affects the rates of X-ray atomic transitions matching the energy of the resonance. The measurement E2 nuclear resonance effect in KMO isotopes allows the study of the strong kaon-nucleus interaction in a rotational excited nuclear state. Moreover, the effect enables the K- to access an inner atomic level not easily reachable by the kaon normal cascade, due to the nuclear absorption. The KAMEO proposed apparatus consists of 4 enriched Mo A=94,96,98,100 isotope strips, exposed to the kaons produced by the DA?NE collider, for kaonic atoms formation, with a high-purity germanium detector, cooled with liquid nitrogen, used to measure the X-ray atomic transitions. The DA?NE collider is located at the National Laboratories of Frascati (LNF-INFN), in Italy. It is already suited for kaonic atoms measurement by the SIDDHARTA-2 collaboration.
Kaonic atoms with SIDDHARTA-2 at the DAFNE collider
F. Sirghi, L. Abbene, M. Bazzi, D. Bosnar, M. Bragadireanu, A. Buttacavoli, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, L. De Paolis, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, F. Sgaramella, S. Niedźwiecki, O. Ohnishi, K. Piscicchia, Y. Sada, A. Scordo, M. Silarski, D.L. Sirghi, M. Skurzok, A. Spallone, S. Wycech, K. Toho, M. Tüchler, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
. The most important information still missing in the field of the low-energy antikaon-nucleon interactions studies is the experimental determination of the hadronic energy shift and width of kaonic deuterium.
This measurement will be performed by the SIDDHARTA-2 experiment, installed at the DA?NE collider
and presently in data taking campaign. The precise measurement of the shift and width of the 1s level with
respect to the purely electromagnetic calculated values, generated by the presence of the strong interaction,
through the measurement of the X-ray transitions to this level, in kaonic hydrogen, was performed by the SIDDHARTA collaboration, the kaonic deuterium is underway by SIDDHARTA-2. These measurement will allow
the first precise experimental extraction of the isospin dependent antikaon-nucleon scattering lengths, fundamental quantities for understanding low-energy QCD in the strangeness sector. The experimental challenge of
the kaonic deuterium measurement is the very small X-rays yield, the even larger width (compared to kaonic hydrogen), and the difficulty to perform X-rays spectroscopy with weak signals in the high radiation environment
of DA?NE. It was, therefore, crucial to develop a new apparatus involving large-area X-rays detector system,
to optimize the signal and to control and by improve the signal-to-background ratio by gaining in solid angle,
increasing the timing capability, and as well implementing additional charge particle tracking veto systems.
SIDDHARTA-2 veto system design and performance for kaonic atoms studies at DAFNE
F. Sgaramella, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, L. De Paolis, L. Fabbietti, C. Fiorini, I. Friscic, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
Light kaonic atoms spectroscopy provides a unique approach to study the low-energy strong interaction in the strangeness sector. Precise measurements of X-ray emission from light kaonic atoms provide valuable information on kaon-nucleus interaction at threshold without the need for extrapolation as required in scattering experiments. The SIDDHARTA-2 experiment at the DA?NE collider of INFN-LNF is now poised to perform the challenging measurements of the K?- d 2p -> 1s transition to extract the isospin-dependent antikaonnucleon scattering lengths. To achieve this goal, the background reduction is a crucial factor. This paper provides an overview of the SIDDHARTA-2 Veto-1 system, which uses scintillators outside the vacuum chamber to detect charged particles produced by K? absorption by the nucleus. The arrival time of these particles is correlated with the position where the kaonic atom has been created inside the setup, allowing for the rejection of kaons stopped outside the target cell, which is a critical component for reducing the background and improve the accuracy of the measurement.
Towards the first kaonic deuterium measurement with the SIDDHARTA-2 experiment
C. Curceanu, L. De Paolis, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, P. Levi Sandri, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, M. Silarski, D. L. Sirghi, F. C. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tuchler, C. Yoshida, J. Zmeskal
abstract
The SIDDHARTA-2 experiment is presently installed at the interaction point of the DA??NE electron-positron collider of the National Laboratories of Frascati (LNF-INFN), in Italy, ready to perform the first measurement of the 2p?1s2p?1s x-ray transition in kaonic deuterium. This measurement, together with that of the kaonic hydrogen 2p?1s2p?1s x-ray transition, performed by the SIDDHARTA experiment in 2009, will allow the determination of antikaon-nucleon isospin-dependent scattering lengths. This paper presents a description of the SIDDHARTA-2 setup, which is getting ready for the kaonic deuterium measurement.
Investigating the E2 nuclear resonance effect in kaonic atoms
L. De Paolis, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, A. Khreptak, P. Levi Sandri, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi. F. Sirghi, M. Skurzok, S. Wycech, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, C. Yoshida, J. Zmeskal and C. Curceanu
abstract
The nuclear E2 resonance effect occurs when an atomic de-excitation energy is closely matched by a nuclear excitation energy. It produces an attenuation of some of the atomic X-ray lines in the resonant isotope target. Investigating the nuclear E2 resonance effect in kaonic atoms, important information about kaon-nucleus strong interaction can be provided. The only ${K}^{-}{-}_{42}^{98}mathrm{Mo}$ nuclear resonance effect was measured by G. L. Goldfrey, G- K. Lum and C. E. Wiegand at Lawrence Berkeley Laboratory, in 1975. The nuclear E2 resonance effect was observed in 25 hours of data taking, not enough to provide a conclusive result. In four kaonic Molybdenum isotopes (${}_{42}^{94}mathrm{Mo}$, ${}_{42}^{96}mathrm{Mo}$, ${}_{42}^{98}mathrm{Mo}$ and ${}_{42}^{100}mathrm{Mo}$), the nuclear E2 resonance effect is expected at the same transition, with similar energy values. The KAMEO (Kaonic Atoms Measuring nuclear resonance Effects Observables) experiment plans to study the E2 nuclear resonance effect in kaonic Molybdenum isotopes at the DA?NE e+e? collider, during the SIDDHARTA-2 experiment. The experimental strategy consists of exposing four solid strip targets, each enriched with one Molybdenum isotope, to negatively charged kaons, using a germanium detector for X-ray transition measurements. A further exposure of a non-resonant ${}_{42}^{92}mathrm{Mo}$ isotope solid strip target will be used as reference for standard non-resonant transitions.
Kaonic atoms measurements with SIDDHARTA-2
F. Sgaramella, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, L. De Paolis, K. Dulski, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Ohnishi, K. Piscicchia, Y. Sada, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M .Skurzok, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, J. Zmeskal, C. Curceanu
abstract
The SIDDHARTA-2 collaboration is aiming to perform the challenging measurement of kaonic deuterium X-ray transitions to the ground state. This will allow to extract the isospin-dependent antikaon-nucleon scattering lengths, providing input to the theory of Quantum Chromodynamics (QCD) in the non-perturbative regime with strangeness. This work describes the SIDDHARTA-2 experimental apparatus and presents the results obtained during the commissioning phase realized with kaonic helium measurements. In particular, the first observation of the kaonic helium transitions to the 3s level (M-lines), reported in this work, represents a new source of information to study the kaonic helium cascade process and demonstrates the potential of the SIDDHARTA-2 apparatus, in the view of the ambitious kaonic deuterium measurement.
The SIDDHARTA-2 experiment: preparation for the first kaonic deuterium measurement
L. De Paolis, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, K. Dulski, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, A. Khreptak, P. Levi Sandri, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi. F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, J. Zmeskal and C. Curceanu
abstract
The SIDDHARTA-2 experiment aims to perform the first measurement of the kaonic deuterium 2p -> 1s x-ray transitions. The apparatus is presently installed at the interaction region of the DAFNE electron-positron collider at the National Laboratories of Frascati (LNF-INFN), in Italy. Kaonic deuterium and kaonic hydrogen 2p -> 1s x-ray transitions measurements, the latter one already performed by the SIDDHARTA collaboration, allow the determination of antikaon-nucleon scattering lengths. A description of the SIDDHARTA-2 apparatus in preparation for the kaonic deuterium measurement is provided in this paper.
Trigger rejection factor in the first kaonic helium run with the complete SIDDHARTA-2 setup
L. De Paolis, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, R. Del Grande, L. Fabbietti, C. Fiorini, I. Friščić, C. Guaraldo, M. Iliescu, M. Iwasaki, A. Khreptak, P. King, P. Levi Sandri, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. L. Sirghi. F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, C. Yoshida, J. Zmeskal and C. Curceanu
abstract
The SIDDHARTA-2 experiment aims to perform the first measurement of the kaonic deuterium 2p -> 1s x-ray transition energy. Such measurement, together with the measurement of kaonic hydrogen 2p -> 1s x-ray energy transition performed by the SIDDHARTA experiment in 2011, allows the determination of kaon proton and kaon neutron scattering lengths and represents a fundamental input for the low energies QCD in the strangeness sector theory. The SIDDHARTA-2 experiment is presently installed at the DAFNE electronpositron collider at the National Laboratories of Frascati, in Italy. In May 2022, the kaonic 4He x-ray transitions measurement was performed by the complete SIDDHARTA-2 setup, by using a gaseous target. The result of this measurement is presented in this paper, with a specific focus on the background rejection performed by the kaon trigger system.
Studies of the Linearity and Stability of Silicon Drift Detectors for Kaonic Atoms X-ray Spectroscopy
A. Khreptak, C. Amsler, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, M. Carminati, A. Clozza, G. Deda, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, S. Manti, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, H. Onishi, K. Piscicchia, Y. Sada, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, K. Toho, M. Tüchler, O. Vazquez Doce, J. Zmeskal, C. Yoshida, C. Curceanu
abstract
The SIDDHARTA-2 experiment at the DAFNE collider aims to perform
precision measurements of kaonic atoms X-ray spectroscopy for the
investigation of the antikaon?nucleon strong interaction. To achieve this
goal, novel large-area Silicon Drift Detectors (SDDs) have been developed.
These devices have special geometry, field configuration, and readout electronics
that ensure excellent performance in terms of linearity and stability.
The paper presents preliminary results for the linearity determination and
stability monitoring of the SDDs system during the measurement of kaonic
deuterium carried out in the summer of 2022.
Status and perspectives for low energy kaon-nucleon interaction studies at DAFNE: from SIDDHARTA to SIDDHARTA-2
F. Sirghi, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
The study of the antikaon nucleon system at very low energies plays a key role for the understanding
of the strong interaction between hadrons in the strangeness sector. The information provided
by the low energy kaon- nucleon interaction is accessible through the study of kaonic atoms.
The lightest atomic systems, namely the kaonic hydrogen and the kaonic deuterium, provide the
isospin dependent kaon-nucleon scattering lengths by measuring the X-rays emitted during their
de-excitation to the 1s level. Until now, the most precise kaonic hydrogen measurement and an
exploratory measurement of kaonic deuterium were carried out at the DA?NE collider by the
SIDDHARTA collaboration, combining the excellent quality kaon beam delivered by the collider
with new experimental techniques, as fast and very precise X-ray detectors, like the Silicon Drift
Detectors. Today, the most important experimental information missing in the field of the lowenergy antikaon-nucleon interactions is the experimental determination of the hadronic energy
shift and width of kaonic deuterium, and will be measured by the new SIDDHARTA-2 experiment,
which is installed in DA?NE and is ready to start the data taking campaign.
High precision Kaonic Deuterium measurement at the DAFNE collider: theSIDDHARTA-2 experiment and the SIDDHARTINO run
M. Miliucci, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, L. De Paolis, R. Del Grande, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, P. Moskal, F. Napolitano, S. Niedźwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi , M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. T ?uchler, O. Vazquez Doce, J. Zmeskal
abstract
The kaonic deuterium 2p?1s transition X-ray measurement, a fundamental information needed for a deeper understanding of the QuantumChromoDynamics (QCD) in the strangeness sector, is still missing. The SIDDHARTA-2 collaboration is now ready to achieve this unprece-dented result thanks to the dedicated experimental apparatus that will allow to obtain the values of the kaonic deuterium K-transitions witha precision comparable to the most precise kaonic hydrogen measurement to-date performed by SIDDHARTA in 2009. Both the kaonichydrogen and kaonic deuterium X-ray spectroscopy measurements of the de-excitation towards the fundamental level are a direct probe onKN interaction at threshold, as opposed to the scattering experiments which need an extrapolation to zero energy. Combining these resultsthrough the Deser-Truemann like formula, the isospin-dependent kaon-nucleon scattering lengths can be obtained in a model-independentway. The SIDDHARTA-2 setup is presently installed at the DAFNE (Double Annular Phi Factory for Nice Experiments) collider of IstitutoNazionale di Fisica Nucleare- Laboratori Nazionali di Frascati and it is ready to perform the challenging kaonic deuterium measurement. Thispaper provides an overview on the SIDDHARTA-2 experimental apparatus and a preliminary result of the kaonic helium run, preparatory forthe SIDDHARTA-2 data taking campaign, is also presented.
Main Features of the SIDDHARTA-2 Apparatus for Kaonic Deuterium X-Ray Measurements
M. Tüchler, F. Sirghi, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, G. Deda, R. Del Grande, L. De Paolis, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. King, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, F. Napolitano, S. Niedzwiecki, K. Piscicchia, A. Scordo, F. Sgaramella, H. Shi, M. Silarski, D. Sirghi, M. Skurzok, A. Spallone, O. Vazquez Doce, E. Widmann, J. Zmeskal
abstract
The low-energy, non-perturbative regime of QCD can be studied directly by X-ray spectroscopy of light kaonic atoms. The SIDDHARTA-2 experiment, located at the DAFNE collider, aims to measure the 2p -> 1s transition in kaonic deuterium for the first time to extract the antikaon-nucleon scattering lengths. This measurement is impeded, inter alia, by the low K?d X-ray yield. Hence, several updates have been implemented on the apparatus to increase the signal-to-background ratio, which are discussed in detail in this paper: a lightweight gas target cell, novel Silicon Drift Detectors for the X-ray detection with excellent performance, and a veto system for active background suppression. The experiment has undergone a first preparatory run during DAFNE?s commissioning phase in 2021, concluding with a successful kaonic helium measurement.
Kaonic atoms measurements at the DAFNE collider: the SIDDHARTA-2 experiment
Catalina Curceanu, Marco Miliucci, Massimiliano Bazzi, Damir Bosnar, Mario Bragadireanu, Marco Carminati, Michael Cargnelli, Alberto Clozza, Griseld Deda, Luca De Paolis, Raffaele Del Grande, Carlo Fiorini, Carlo Guaraldo, Mihail Iliescu, Masahiko Iwasaki, Pietro King, Paolo Levi Sandri, Johann Marton, Paweł Moskal, Fabrizio Napolitano, Szymon Niedźwiecki, Kristian Piscicchia, Alessandro Scordo, Francesco Sgaramella, Hexi Shi, Michał Silarski, Diana Sirghi, Florin Sirghi, Magdalena Skurzok, Antonio Spallone, Marlene Tüchler, Oton Vazquez Doce, Johann Zmeskal
abstract
The X-ray spectroscopy measurements of light kaonic atoms? deexcitation towards the fundamental level provide unique information on the low-energy Quantum ChromoDynamics (QCD) in the strangeness sector, being a direct probe of the kaon/nucleon interaction at threshold, unobtainable through the scattering experiments. In this framework, the SIDDHARTA-2 collaboration is going to perform the first kaonic deuterium 2p -> 1s transition measurement at the DAFNE collider of Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati. Combining this measurement with the kaonic hydrogen one performed by SIDDHARTA in 2009 it will be possible to obtain, in a model-independent way, the isospin-dependent antikaon-nucleon scattering lengths. The paper introduces the SIDDHARTA-2 setup, an upgraded version with respect to the one used for the kaonic hydrogen measurement, dedicated to the ambitious kaonic deuterium measurement, together with the preliminary results obtained during the kaonic helium run, preparatory for the SIDDHARTA-2 data taking campaign.
Probing low-energy QCD with kaonic atoms at DAFNE
M. Tuchler, J. Zmeskal, A. Amirkhani, C. Amsler, A. Baniahmad, M. Bazzi, D. Bosnar, M. A. Bragadireanu, P. Buhler, M. Cargnelli, M. Carminati, A. Clozza, C. Curceanu, R. Del Grande, L. De Paolis, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedzwiecki, S. Okada, K. Piscicchia, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, O. Vazquez Doce and E. Widmann
abstract
X-ray spectroscopy of kaonic atoms provides a versatile tool to study the strong interaction at low energies via a direct observation of its influence on the ground state of kaonic hydrogen atoms. The SIDDHARTA experiment provided precise results on the energy shift and width of the kaonic hydrogen 1s state induced by the strong interaction. To enable the extraction of the antikaon-nucleon scattering lengths a0 and a1, SIDDHARTA-2 aims to determine the energy shift and width in kaonic deuterium with precisions of 30 eV and 75 eV, respectively. This measurement is aggravated by the low kaonic deuterium X-ray yield and a high background environment and will only be possible by implementing a severe upgrade on the SIDDHARTA apparatus.
Low-energy Kaon Nucleon/Nuclei Studies at DAFNE: the SIDDHARTA-2 Experiment
M. Miliucci, A. Amirkhani, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, C. Curceanu, A. Clozza, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, P. Moskal, S. Niedźwiecki, S. Okada, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, J. Zmeskal
abstract
The experimental studies of light kaonic atoms offer the unique opportunity to investigate the kaon-nucleus interaction at threshold, performing experiments equivalent to scattering at vanishing relative energies without the need of an extrapolation. In this framework, the SIDDHARTA-2 experiment is going to perform the first measurement of kaonic deuterium 2p->1s transition, which is fundamental to extract the isospin-dependent antikaon-nucleon scattering lengths. The setup was installed on the DAFNE collider of LNF-INFN in spring 2019 and is presently in optimization phase. The SIDDHARTA-2 data taking campaign for the kaonic deuterium is planned in 2020-2021.
Studies of kaonic atoms at the DAFNE collider: from SIDDHARTA to SIDDHARTA-2
D. Sirghi, A. Amirkhani, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedźwiecki, S. Okada, D.Pietreanu, K. Piscicchia, A. Scordo, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, M. Tüchler, O. Vazquez Doce, E. Widmann, J. Zmeskal
abstract
The DA?NE electron-positron collider of the Laboratori Nazionali di Frascati of INFN is a worldwide unique low-energy kaon source and for this reason is suitable for low-energy kaon physics like kaonic atoms and kaon-nucleons/nuclei interaction studies. Kaonic atoms are atomic systems where an electron is replaced by a negatively charged kaon, containing the strange quark, which interacts in the lowest orbits with the nucleus also by the strong interaction. As a result, their study offers the unique opportunity to perform experiments equivalent to scattering at vanishing relative energy. This allows to study the strong interaction between the antikaon and the nucleon or the nucleus at threshold, without the need of ad hoc extrapolation to zero energy, as in scattering experiments. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA collaboration at the DA?NE electron-positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise Silicon-Drift X-ray Detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA.
Kaonic Deuterium Precision Measurement at DAFNE: The SIDDHARTA-2 Experiment
M. Miliucci, A. Amirkhani, A. Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, C. Curceanu, A. Dawood Butt, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, P. Moskal, S. Nied ? wiecki, z S. Okada, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann and J. Zmeskal
abstract
Light kaonic atoms spectroscopy offers the unique opportunity to perform experiments equivalent to scattering at vanishing relative energies. This allows the determination of the antikaon-nucleus interaction at threshold, without the need of extrapolation to zero energy, as in the case of scattering experiments. In this framework, the SIDDHARTA-2 collaboration aims to perform the first measurement of kaonic deuterium transition to the fundamental level, which is mandatory to extract the isospin dependent antikaon-nucleon scattering lengths. The experiment will be carried out at the DA?NE collider of LNF-INFN in 2019-2020.
Kaonic atoms experiment at the DAFNE collider by SIDDHARTA/SIDDHARTA-2
M. Skurzok, A. Amirkhani, A. Baniahmad, M. Bazzi, D. Bosnar, M. Bragadireanu, M. Carminati, M. Cargnelli, A. Clozza, C. Curceanu, L. De Paolis, R. Del Grande, L. Fabbietti, C. Fiorini, C. Guaraldo, M. Iliescu, M. Iwasaki, P Levi Sandri, J. Marton, M. Miliucci, P Moskal, S. Niedzwiecki, S. Okada, D. Pietreanu, K. Piscicchia, A. Scordo, M. Silarski, D. Sirghi, F. Sirghi, A. Spallone, M. Tüchler, O. Vazquez Doce, E. Widmann and J. Zmeskal
abstract
The excellent quality kaon beam provided by the DAFNE collider of LNF-INFN (Italy)
together with SIDDHARTA/SIDDHARTA-2 new experimental techniques, as very precise
and fast-response X-ray detectors, allow to perform unprecedented measurements on
light kaonic atoms crucial for a deeper understanding of the low-energy quantum chro-
modynamics (QCD) in the strangeness sector. In this paper an overview of the main
results obtained by the SIDDHARTA collaboration, as well as the future plans related to
the SIDDHARTA-2 experiment, are discussed.
Probing Strong Interaction with SIDDHARTA-2
J. Zmeskal, A. Scordo, A. Amirkhani, C. Amsler, A. Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, C. Curceanu, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. L. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, M. Tuechler, O. Vazquez Doce, E. Widmann
abstract
The antikaon-nucleon interaction close to threshold provides crucial information on the
interplay between spontaneous and explicit chiral symmetry breaking in low-energy QCD
involving strangeness. The unique feature of DAFNE, namely the production of low-energy
kaons, has led to a series of successfully conducted experiments with light kaonic atoms like
SIDDHARTA, where the most precise value for the antikaon-proton scattering length was
determined. Kaonic deuterium X-ray spectroscopy is still missing and with SIDDHARTA-2 the
ground state 1s-level shift and width should be measured with a precision of 30 eV and 75 eV,
respectively.
Kaonic atoms measurements at the DAFNE Collider
D. Sirghi, A. Amirkhani, A. Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, C. Curceanu, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, J. Martona, M. Miliucci, P. Moskal, S. Niedzwiecki, S. Okada, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, E. Widmann, J. Zmeskal
abstract
The DAFNE electron-positron collider of the Laboratori Nazionali di Frascati of INFN is a worldwide unique low-energy kaon source, which is being used to produce and to study kaonic atoms by the SIDDHARTA collaboration. The X-ray measurements of kaonic atoms play an important role for understanding the low-energy QCD in the strangeness sector. Significant achievements have been obtained by the SIDDHARTA experiment, among which: the most precise kaonic hydrogen measurement of the 1s level shift and width induced by the presence of the strong interaction; an upper limit of the X-ray yield for kaonic deuterium K-series; the accurate measurement of the 2p level shift and width of kaonic helium-4 and kaonic helium-3; yields of various light kaonic atoms transitions. Using the experience gained with SIDDHARTA experiment, the first kaonic deuterium measurement is in preparation in the framework of the SIDDHARTA-2 experiment with the goal to determine the antikaon-nucleon isospin dependent scattering lengths, which is possible only by combining the K-p and the upcoming K-d results. An overview of the experimental results of SIDDHARTA and an outlook to SIDDHARTA-2 experiments are given in this paper.
Kaonic Atoms Measurement at DAFNE: SIDDHARTA and SIDDHARTA-2
L. De Paolis, D. Sirghi, A. Amirkhani, A. Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, C. Curceanu, A. Dawood Butt, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedźwiecki, S. Okada, D. Pietreanu, K. Piscicchia, H. Shi, M. Silarski, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann and J. Zmeskal
abstract
Light kaonic atoms studies provide the unique opportunity to perform experiments equivalent to scattering at threshold, being their atomic binding energies in the keV range. High precision atomic X-rays spectroscopy ensures that the energy shift and broadening of the lowest-lying states of the kaonic atoms, induced by the strong interaction between the kaon and nucleus, can be detected. Kaonic hydrogen and kaonic deuterium are the lightest atomic systems and their study deliver the isospin-dependent kaon-nucleon scattering lengths. The SIDDHARTA collaboration was able to perform the most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium. The measurement of the kaonic deuterium will be realized in the near future by a major upgrade of SIDDHARTA: SIDDHARTA-2. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans are presented.
Spectroscopy of kaonic atoms at DAFNE and J-PARC
J. Marton, A. Amirkhan, A. Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, M. Bragadireanu, M. Cargnelli, C. Curceanu, A. Dawood Butt, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P. Levi Sandri, M. Miliucci, P. Moskal, S. Niedźwiecki, S. Okada, D. Pietreanu, K. Piscicchia, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann and J. Zmeskal
abstract
The interaction of antikaons (K-) with nucleons and nuclei in the low-energy regime represents a very active research field in hadron physics. A unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states in the lightest kaonic atoms (i.e. kaonic hydrogen and deuterium). In the SIDDHARTA experiment at the electron-positron collider DAFNE of LNFINFN we measured the most precise values of the strong interaction observables in conic hydrogen. The strong interaction on the 1s ground state of the electromagnetically bound K-p atom causes an energy shift and broadening of the 1s state. SIDDHARTA will extend the spectroscopy to kaonic deuterium to get access to the antikaon-neutron interaction and thus the isospin dependent scattering lengths. At J-PARC a kaon beam is used in a complementary experiment with a different setup for spectroscopy of kaonic deuterium atoms. The talk will give an overview of the of the upcoming experiments SIDDHARTA and the complementary experiment at J-PARC.Furthermore, the implications of the experiments for the theory of low-energy strong interaction with strangeness will be discussed.
A charged particle veto detector for kaonic deuterium measurements at DAFNE
M. Tüchler, J. Zmeskal, A. Amirkhani, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, A.M. Bragadireanu, M. Cargnelli, C. Curceanu, A. Dawood Butt, R. Del Grande, L. De Paolis, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, R.S. Hayano, M. Iliescu, M. Iwasaki, P.Levi Sandri, J. Marton, M. Miliucci, P. Moskal, D. Pietreanu, K. Piscicchia, A. Scordo, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, O. Vazquez Doce, E. Widmann
abstract
The antikaon-nucleon interaction close to threshold provides crucial information on the interplay between spontaneous and explicit chiral symmetry breaking in low-energy QCD. In this context, the importance of kaonic deuterium x-ray spectroscopy has been well recognized, but no experimental results have yet been obtained due to the difficulty of the measurement. To measure the shift and width of the kaonic deuterium 1s state with an accuracy of 30 eV and 75 eV, respectively, an apparatus is under construction at the Laboratori Nazionali di Frascati. A detailed Monte Carlo simulation has shown that an increase of the signal to background ratio by a factor of ten will be required compared to the successfully performed kaonic hydrogen measurement (SIDDHARTA). Three pillars are essential for the newly developed experimental apparatus: a large area x-ray detector system (consisting of Silicon Drift Detectors), a lightweight cryogenic target system and a veto system, consisting of an outer veto detector (Veto-1) for active shielding and an inner veto detector (Veto-2) for charged particle suppression. For both veto systems, an excellent time resolution is required to distinguish kaons stopping in gas from direct kaon stops in the entrance window or side wall of the target. First test measurements on the Veto-2 system were performed. An average time resolution of (54 +- 2) ps and detection efficiencies of ~ 99 % were achieved.
The kaonic atoms research program at DAFNE: overview and perspectives
C. Curceanu, A. Amirkhani, A Baniahmad, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, A.M. Bragadireanu, M. Cargnelli, A. Dawood Butt, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, M. Iliescu, M. Iwasaki, P.Levi Sandri, J. Marton, M. Miliucci, P. Moskal, S. Niedzwiecki, S. Okada, D. Pietreanu, K. Piscicchia, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann, J. Zmeskal
abstract
The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The energy shift and broadening of the lowest-lying states of such atoms, induced by the kaon-nucleus strong interaction, can be determined with high precision from atomic X-ray spectroscopy. This experimental method provides unique information to understand the low energy kaon-nucleus interaction at threshold. The lightest atomic systems, kaonic hydrogen and kaonic deuterium, deliver the isospin-dependent kaon-nucleon scattering lengths. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA collaboration at the DAFNE electron-positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise X-ray detectors: Silicon Drift Detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans, are given.
A New Silicon Drift Detector System for Kaonic Atom Measurements
C. Trippl, ..., R. Del Grande, ..., P. Moskal, ...
abstract
The kaonic deuterium measurement at J-PARC and DAFNE will provide a piece of information still missing to the antikaon-nucleon interaction close to threshold, providing valuable information to answer one of the most fundamental problems in hadron physics today - to the yet unsolved puzzle of how the hadron mass is generated. For this a new X-ray detector system has been developed to measure the shift and width of the 2p -> 1s transition of kaonic deuterium with a precision of 60 eV and 140 eV, respectively.
The kaonic atoms research program at DAFNE: from SIDDHARTA to SIDDHARTA-2
A. Scordo, A. Amirkhani, M. Bazzi, G. Bellotti, C. Berucci, D. Bosnar, A.M. Bragadireanu, M. Cargnelli, C. Curceanu, A. Daewood Butt, R. Del Grande, L. Fabbietti, C. Fiorini, F. Ghio, C. Guaraldo, R.S. Hayano, M. Iliescu, M. Iwasaki, P. Levi Sandri, J. Marton, M. Miliucci, P. Moskal, D. Pietreanu, K. Piscicchia, H. Shi, M. Silarski, D. Sirghi, F. Sirghi, M. Skurzok, A. Spallone, H. Tatsuno, O. Vazquez Doce, E. Widmann, J. Zmeskal
abstract
The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms, in which one electron is replaced by a negatively charged kaon, is a unique tool to provide precise information on this interaction; the energy shift and the broadening of the low-lying states of such atoms, induced by the kaon-nucleus hadronic interaction, can be determined with high precision from the atomic X-ray spectroscopy, and this experimental method provides unique information to understand the low energy kaon-nucleus interaction at the production threshold. The lightest atomic systems, like the kaonic hydrogen and the kaonic deuterium deliver, in a model-independent way, the isospin-dependent kaon-nucleon scattering lengths. The most precise kaonic hydrogen measurement to-date, together with an exploratory measurement of kaonic deuterium, were carried out in 2009 by the SIDDHARTA collaboration at the DA?NE electron-positron collider of LNF-INFN, combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and very precise X-ray detectors, like the Silicon Drift Detectors. The SIDDHARTA results triggered new theoretical work, which achieved major progress in the understanding of the low-energy strong interaction with strangeness reflected by the antikaon-nucleon scattering lengths calculated with the antikaon-proton amplitudes constrained by the SIDDHARTA data. The most important open question is the experimental determination of the hadronic energy shift and width of kaonic deuterium; presently, a major upgrade of the setup, SIDDHARTA-2, is being realized to reach this goal. In this paper, the results obtained in 2009 and the proposed SIDDHARTA-2 upgrades are presented.
Probing Strong Interaction with Kaonic Atoms from DAFNE to J-PARC
J. Zmeskal, ...,P. Moskal, et al.
abstract
The study of the antikaon nucleon system at very low energies plays a key role to study strong interaction with strangeness, touching one of the fundamental problems in hadron physic today???the still unsolved question of how hadron masses are generated. Exotic atoms offer a unique possibility to determine s-wave kaon-nucleon scattering lengths at vanishing energy. At the DAFNE electron positron collider of Laboratori Nazionali di Frascati in the SIDDHARTA experiment kaonic atoms were formed with Z = 1 (K-p) and Z = 2 (K-He), which were measured with up to now unrivalled precision. This experiment is taking advantage of the low-energy charged kaons from phi-mesons decaying nearly at rest. Finally, using the experience gained with SIDDHARTA, a proposal to measure kaonic deuterium for the first time was submitted to J-PARC with the goal to determine the isospin dependent scattering lengths, which is only possible by combining the K-p and the upcoming K-d results.
