Doctoral thesis
Study of the phi->eta e+e- dalitz decay using KLOE detector
Supervisor: prof. Paweł Moskal
abstractIn this thesis the results of the investigation of the phi -> eta e+ e- -> pi+ pi- pi0 e+ e- reaction are presented. The goal of this work is to extract the branching ratio of the phi -> eta e+ e- decay, the slope of an electromagnetic transition form factor of phi-eta mesons and a charge radius of the phi meson. For this aim the phi mesons were produced in the electron-positron collisions and the eta mesons were identified via the eta -> pi0 pi+ pi- decay channel. The measurement was performed using the KLOE detector and the electron-positron beams circulated in the DAPhiNE accelerator. The experimental data used in this thesis has been collected in 2004-2005 years. After selection of the final sample, we reconstructed around 13000 events coming from phi -> eta e+e- -> pi0 pi+ pi- e+ e- decay with less than 2% background. Thus improving the statisticscollected by previous experiments by about two orders of magnitude. The extracted values of form factor slope parameter,b , branching ratio, BR and the radius of phi meson for analyzed reaction are: b = 1.32 +/- 0.23stat +/- 0.02syst GeV-2 , BR = (1.170 +/- 0.035stat +/- 0.008syst ) * 10-4 , radius = 0.56 +/- 0.05 fm, respectively. The results for slope of transition form factor, branching ratio and the charge radius of phi meson are delivered with the biggest precision ever.
Diploma thesis
Merging and splitting of clusters in the electromagnetic calorimeter of the KLOE detector
Supervisor: prof. Paweł Moskal
The work was carried out in the framework of the KLOE collaboration studying the decays of the phi meson produced in the DAFNE accelerator in the collisions of electron and positron. The main aim of this thesis was investigation of the influence of the merging and splitting of clusters in decays with the high multiplicity of gamma quanta, which are at most biased by these effects. For this aim we implemented the full geometry and realistic material composition of the barrel electromagnetic calorimeter in FLUKA package. The prepared Monte Carlo based simulation program permits to achieve a fast generation of the detector response separately for each interested reaction. The program was used to study the reconstruction efficiency with the KLOE clustering algorithm as a function of the photocathode quantum efficiency. It was also used to investigate merging and splitting probabilities as a function of the quantum efficiency. The conducted studies indicated that the increase of quantum efficiency does not improve significantly the identification of clusters. The influence of these effects was estimated for eta meson decays into 3 neutral pions and K_short meson into 2 neutral pions.
Publications
ARTICLES CONFERENCE PROCEEDINGS POSTERS
- Search for light vector boson production in e+e- -> mi+mi- gamma interactions with the KLOE experimentD. Babusci, I. Balwierz-Pytko, E. Czerwiński, A. Gajos, D. Kamińska, W. Krzemień, P. Moskal, M. Silarski, J. Zdebik, et al.We have searched for a light vector boson U, the possible carrier of a dark force, with the KLOE detector at the DAFNE e+e- collider, motivated by the astrophysical evidence for the presence of dark matter in the universe. Using e+e- collisions collected for an integrated luminosity of 239.3~pb?1, we look for a dimuon mass peak in the reaction e+e- -> mu+mu-gamma, corresponding to the decay U->mu+mu-. We find no evidence for a U vector boson signal. We set a 90% CL upper limit for the mixing parameter squared between the photon and the U boson of 1.6×10^5 to 8.6×10^7 for the mass region 520Test of CPT and Lorentz symmetry in entangled neutral kaons with the KLOE experimentD. Babusci, ..., I. Balwierz-Pytko, E. Czerwiński, A. Gajos, K. Kacprzak, D. Kamińska, P. Moskal, M. Silarski, W. Wiślicki, J. Zdebik et al.Neutral kaon pairs produced in phi decays in anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis of the CP-violating process phi->K_S K_L->pi+pi-pi+pi- based on 1.7 fb-1 of data collected by the KLOE experiment at the Frascati phi-factory DAFNE. The data are used to perform a measurement of the CPT-violating parameters Delta_amu for neutral kaons in the contest of the Standard Model Extension framework. The parameters measured in the reference frame of the fixed stars are: Delta_ao = (-6.0 +- 7.7_{stat} +- 3.1_{syst}) x 10^{-18} GeV Delta_ax = ( 0.9 +- 1.5_{stat} +- 0.6_{syst}) x 10^{-18} GeV Delta_ay = (-2.0 +- 1.5_{stat} +- 0.5_{syst}) x 10^{-18} GeV Delta_az = ( 3.1 +- 1.7_{stat} +- 0.5_{syst}) x 10^{-18} GeV These are presently the most precise measurements in the quark sector of the Standard Model Extension.A new limit on the CP violating decay KS -> 3pi0 with the KLOE experimentD. Babusci, ..., I. Balwierz-Pytko, E. Czerwiński, P. Moskal, M. Silarski, W. Wiślicki, J. Zdebik et al.We have carried out a new direct search for the CP violating decay KS -> 3pi0 with 1.7 fb^-1 of e+e- collisions collected by the KLOE detector at the phi-factory DAFNE. We have searched for this decay in a sample of about 5.9 x 10^8 KS KL events tagging the KS by means of the KL interaction in the calorimeter and requiring six prompt photons. With respect to our previous search, the analysis has been improved by increasing of a factor four the tagged sample and by a more effective background rejection of fake KS tags and spurious clusters. We find no candidates in data and simulated background samples, while we expect 0.12 standard model events. Normalizing to the number of KS -> 2pi0 events in the same sample, we set the upper limit on BR(KS -> 3pi0 < 2.6 x 10^-8 at 90% C.L., five times lower than the previous limit. We also set the upper limit on the eta_000 parameter, |eta_000 | < 0.0088 at 90% C.L., improving by a factor two the latest direct measurement.TOF-PET detector concept based on organic scintillatorsP. Moskal, T. Bednarski, P. Białas, M. Ciszewska, E. Czerwiński, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka-Cupiał, G. Korcyl, W. Krzemień, K. Łojek, J. Majewski, W. Migdał, M. Molenda, S. Niedźwiecki, M. Pałka, Z. Rudy, P. Salabura, M. Silarski, A. Słomski, J. Smyrski, J. Zdebik, M. ZielińskiIn this contribution we present a new concept of the large acceptance detector systems based on organic scintillators which may allow for simultaneous diagnostic of large fraction of the human body. Novelty of the concept lies in employing large blocks of polymer scintillators instead of crystals as detectors of annihilation quanta, and in using predominantly the timing of signals instead of their amplitudes.Strip-PET: a novel detector concept for the TOF-PET scannerP. Moskal, T. Bednarski, P. Białas, M. Ciszewska, E. Czerwiński, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka-Cupiał, G. Korcyl, W. Krzemień, K. Łojek, J. Majewski, W. Migdał, M. Molenda, S. Niedźwiecki, M. Pałka, Z. Rudy, P. Salabura, M. Silarski, A. Słomski, J. Smyrski, J. Zdebik, M. ZielińskiWe briefly present a design of a new PET scanner based on strips of polymer scintillators arranged in a barrel constituting a large acceptance detector. The solution proposed is based on the superior timing properties of the polymer scintillators. The position and time of the reaction of the gamma quanta in the detector material will be determined based on the time of arrival of light signals to the edges of the scintillator strips.Measurement of eta meson production in gamma-gamma interactions and Gamma(eta-->gamma gamma) with the KLOE detectorD. Babusci, ..., I. Balwierz-Pytko, E. Czerwiński, P. Moskal, M. Silarski, W. Wiślicki, J. Zdebik et al.We present a measurement of {eta} meson production in photon-photon interactions produced by electron-positron beams colliding with sqrt{s}=1 GeV. The measurement is done with the KLOE detector at the phi-factory DA{Phi}NE with an integrated luminosity of 0.24 fb^{-1}. The e^+e^- --> e^+e^-{eta} cross section is measured without detecting the outgoing electron and positron, selecting the decays {eta}-->{pi}^+{pi}^-{pi}^0 and {eta}-->{pi}^0{pi}^0{pi}^0. The most relevant background is due to e^+e^- --> {eta}{gamma} when the monochromatic photon escapes detection. The cross section for this process is measured as {sigma}(e^+e^- -->{eta}{gamma}) = (856 pm 8_{stat} pm 16_{syst}) pb. The combined result for the e^+e^- -->e^+e^-{eta} cross section is {sigma}(e^+e^- -->e^+e^-{eta}) = (32.72 pm 1.27_{stat} pm 0.70_{syst}) pb. From this we derive the partial width {Gamma}({eta}-->{gamma}{gamma}) = (520 pm 20_{stat} pm 13_{syst}) eV. This is in agreement with the world average and is the most precise measurement to date.Limit on the production of a light vector gauge boson in phi meson decays with the KLOE detectorD. Babusci, ..., I. Balwierz-Pytko, E. Czerwiński, P. Moskal, M. Silarski, W. Wiślicki, J. Zdebik, et alWe present a new limit on the production of a light dark-force mediator with the KLOE detector at DAPHNE. This boson, called U, has been searched for in the decay phi -->eta U, with the hypothesis U-->e+e-, analyzing the decay eta-->pi0pi0pi0 in a data sample of 1.7 fb-1 integrated luminosity. This search is combined with a previous result obtained using the decay eta-->pi+pi-pi0, increasing substantially the sensitivity. No structures are observed in the e+e- invariant mass distribution over the background. Combining the two eta decay modes, we set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of alpha'/alpha <= 1.5x10^-5 for 30Precision measurement of sigma(e+e-->pi+pi-gamma)/sigma(e+e-->mu+mu-gamma) and determination of the pi+pi- contribution to the muon anomaly with the KLOE detectorD. Babusci, ..., P. Moskal, E. Czerwiński, I. Balwierz-Pytko, M. Silarski, W. Wiślicki, J. Zdebik et al.We have measured the ratio $sigma(e^+e^- ightarrowpi^+pi^-gamma)/sigma(e^+e^- ightarrow mu^+mu^-gamma)$, with the KLOE detector at DA$Phi$NE for a total integrated luminosity of $sim$ 240 pb$^{-1}$. From this ratio we obtain the cross section $sigma(e^+e^- ightarrowpi^+pi^-)$. From the cross section we determine the pion form factor $|F_pi|^2$ and the two-pion contribution to the muon anomaly $a_mu$ for $0.592Measurement of Gamma(eta->pi^+pi^-gamma)/Gamma(eta->pi^+pi^-pi^0) with the KLOE DetectorD. Babusci, ..., I. Balwierz-Pytko, E. Czerwiński, M. Silarski, P. Moskal, J. Zdebik, et al.Measurement of gamma(eta->pi+pi-gamma)/gamma(eta->pi+pi-pi0) with KLOE experimentD. Babusci, ..., P. Moskal, ..., E. Czerwiński, ..., J. Balwierz, ..., M. Silarski, ..., J. Zdebik et al.We report the measurement of the ratio $Gamma(eta o pi^+pi^-gamma)/Gamma(eta o pi^+pi^-pi^0)$ analyzing a large sample of $phi o eta gamma$ decays recorded with the KLOE experiment at the DA$Phi$NE $e^+ e^-$ collider, corresponding to an integrated luminosity of 558 pb$^{-1}$. The $eta o pi^+pi^-gamma$ process is supposed to proceed both via a resonant contribution, mediated by the $ ho$ meson, and a non resonant direct term, connected to the box anomaly. The presence of the direct term affects the partial width value. Our result $R_{eta}=Gamma(eta o pi^+ pi^- gamma)/Gamma(eta o pi^+ pi^- pi^0)= 0.1838pm 0.0005_{stat} pm 0.0030_{syst}$ is in agreement with a recent CLEO measurement, which differs by more 3 $sigma$ from the average of previous results.On the possibility to measure the (pi0 to gamma gamma) decay width and the (gamma* gamma to pi0) transition form factor with the KLOE-2 experimentD. Babusci, ..., and KLOE-2 Collaboration: F. Archilli, ..., I. Balwierz, E. Czerwiński, P. Moskal, M. Silarski, J. Zdebik et al.A possibility of KLOE-2 experiment to measure the width Gamma(pi0 to gamma gamma) and the (pi0 gamma gamma*) form factor F(Q^2) at low invariant masses of the virtual photon in the space-like region is considered. This measurement is an important test of the strong interaction dynamics at low energies. The feasibility is estimated on the basis of a Monte-Carlo simulation. The expected accuracy for Gamma(pi0 to gamma gamma) is at a per cent level, which is better than the current experimental world average and theory. The form factor will be measured for the first time at Q^2 less or equal 0.1 GeV^2 in the space-like region. The impact of these measurements on the accuracy of the pion-exchange contribution to the hadronic light-by-light scattering part of the anomalous magnetic moment of the muon is also discussed.Search for a vector gauge boson in phi meson decays with the KLOE detectorF. Ambrosino, ..., I. Balwierz, E. Czerwiński, P. Moskal, M. Silarski, J. Zdebik et al.The existence of a light dark force mediator has been tested with the KLOE detector at DAFNE. This particle, called U, is searched for using the decay chain phi->eta U, eta->pi+pi-pi0, U->e+e-. No evidence is found in 1.5 fb-1 of data. The resulting exclusion plot covers the mass range 5Novel detector systems for the Positron Emission TomographyP. Moskal, P. Salabura, M. Silarski, J. Smyrski, J. Zdebik, M. ZielińskiIn this contribution we describe a novel solution for the construction of Positron Emission Tomograph. We present the device allowing for determination of the impact position as well as time and depth of interaction of the annihilation gamma quanta. The device is comprised of scintillation chamber consisting of organic scintillators surrounding the body of the patient. We discuss two possible solutions: (i) the tomograph built out of scintillator strips, and (ii) the tomograph built out of the scintillator plates. The application of the fast scintillators will enable to take advantage of the difference between time of the registration of the annihilation quanta. The invented method will permit to use a thick layers of detector material with the possibility of measuring the depth of the gamma quantum interaction (DOI) and the determination of their time of fl ight (TOF), and will allow for increasing the size of the diagnostic chamber without a signifi cant increase of costs. The method is a subject of two patent applications [1, 2] which are based on the techniques used in the particle physics experiments [3, 4].Observation of the rare eta->e+e-e+e- decay with the KLOE experimentF. Ambrosino, ..., I. Balwierz, E. Czerwiński, P. Moskal, M. Silarski, J. Zdebik et al.We report the first observation of the rare eta->e+e-e+e- decay based on 1.7 fb^{-1} collected by the KLOE experiment at the DAFNE phi-factory. The selection of the e+e-e+e- final state is fully inclusive of radiation. We have identified 362 +- 29 events resulting in a branching ratio of (2.4 +- 0.2_stat+bckg +- 0.1_syst) x 10^{-5}.gamma gamma physics with the KLOE experimentF. Archilli, ..., P. Moskal, E. Czerwiński, J. Zdebik, J. Balwierz, M. Silarski et al.The processes $e^+e^- o e^+e^-X$, with $X$ being either the $eta$ meson or $pi^0pi^0$, are studied at DA$Phi$NE, with $e^+e^-$ beams colliding at $sqrt{s}simeq1$ GeV, below the $phi$ resonance peak. The data sample is from an integrated luminosity of 240 pb$^{-1}$, collected by the KLOE experiment without tagging of the outgoing $e^+e^-$. Preliminary results are presented on the observation of the $gammagamma oeta$ process, with both $eta opi^+pi^-pi^0$ and $eta opi^0pi^0pi^0$ channels, and the evidence for $gammagamma opi^0pi^0$ production at low $pi^0pi^0$ invariant mass.Determination of the total width of the eta-prime mesonE. Czerwiński, P. Moskal, D. Grzonka, R. Czyżykiewicz, D. Gil, B. Kamys, A. Khoukaz, J. Klaja, P. Klaja, W. Krzemień, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Täschner, M. Wolke, P. Wüstner, J. Zdebik, M. Zieliński, W. ZipperTaking advantage of both the low-emittance proton beam of the cooler synchrotron COSY and the high momentum precision of the COSY-11 detector system, the mass distribution of the eta-prime meson was measured with a resolution of 0.33??MeV/c2 (FWHM), improving the experimental mass resolution by almost an order of magnitude with respect to previous results. Based on the sample of more than 2300 reconstructed pp->pp eta-prime events, the total width of the eta-prime meson was determined to be Gamma(eta-prime) = 0.226+-0.017(stat)+-0.014(syst)??MeV/c2.Proposal for taking data with the KLOE-2 detector at the DAFNE collider upgraded in energyD. Babusci, ..., P. Moskal, E. Czerwiński, I. Balwierz, M. Silarski, J. Zdebik, et al.This document reviews the physics program of the KLOE-2 detector at DA$Phi$NE upgraded in energy and provides a simple solution to run the collider above the $phi$-peak (up to 2, possibly 2.5 GeV). It is shown how a precise measurement of the multihadronic cross section in the energy region up to 2 (possibly 2.5) GeV would have a major impact on the tests of the Standard Model through a precise determination of the anomalous magnetic moment of the muon and the effective fine-structure constant at the $M_Z$ scale. With a luminosity of about $10^{32}$cm$^{-2}$s$^{-1}$, DA$Phi$NE upgraded in energy can perform a scan in the region from 1 to 2.5 GeV in one year by collecting an integrated luminosity of 20 pb$^{-1}$ (corresponding to a few days of data taking) for single point, assuming an energy step of 25 MeV. A few years of data taking in this region would provide important tests of QCD and effective theories by $gammagamma$ physics with open thresholds for pseudo-scalar (like the $eta'$), scalar ($f_0,f'_0$, etc...) and axial-vector ($a_1$, etc...) mesons; vector-mesons spectroscopy and baryon form factors; tests of CVC and searches for exotics. In the final part of the document a technical solution for the energy upgrade of DA$Phi$NE is proposed.Physics with the KLOE-2 experiment at the upgraded DAFNEG. Amelino-Camelia, ..., E. Czerwiński, P. Moskal, M. Silarski, J. Zdebik et al.Investigation at a $phi$--factory can shed light on several debated issues in particle physics. We discuss: i) recent theoretical development and experimental progress in kaon physics relevant for the Standard Model tests in the flavor sector, ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled kaon states, iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and eta/eta$^prime$ mesons, iv) the contribution to understand the nature of light scalar mesons, and v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the $e^+ e^-$ physics in the continuum with the measurements of (multi)hadronic cross sections and the study of gamma gamma processes.Two-proton correlation function for the pp -> pp + eta and pp to pp + pions reactionsP. Klaja, P. Moskal, E. Czerwiński, R. Czyżykiewicz, A. Deloff, D. Gil, D. Grzonka, B. Kamys, A. Khoukaz, J. Klaja, W. Krzemień, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Täschner, M. Wolke, J. Zdebik, M. Zieliński, W. ZipperFor the very first time, the correlation femtoscopy method is applied to a kinematically complete measurement of meson production in the collisions of hadrons. A two-proton correlation function was derived from the data for the pp -> ppX reaction, measured near the threshold of eta meson production. A technique developed for the purpose of this analysis permitted the correlation function to be established separately for the production of the pp + eta and of the pp + pions systems. The shape of the two-proton correlation function for pp-eta differs from that for pp(pions) and both do not show a peak structure, opposite to the results determined for inclusive measurements of heavy ion collisions.Two-proton correlation function for the pp -> pp plus eta and pp -> pp plus pions reactionsP. Klaja, P. Moskal, E. Czerwinski, R. Czyzykiewicz, A. Deloff, D. Gil, D. Grzonka, B. Kamys, A. Khoukaz, J. Klaja, W. Krzemien, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, J. Zdebik, M. Zielinski, W. ZipperFor the very first time, the correlation femtoscopy method is applied to a kinematically complete measurement of meson production in the collisions of hadrons. A two-proton correlation function was derived from the data for the pp -> ppX reaction, measured near the threshold of eta meson production. A technique developed for the purpose of this analysis permitted the correlation function to be established separately for the production of the pp + eta and of the pp + pions systems. The shape of the two-proton correlation function for pp eta differs from that for pp(pions) and both do not show a peak structure, opposite to the results determined for inclusive measurements of heavy ion collisions.Upper limit of the total cross section for the pn->pn eta-prime reactionJ. Klaja, P. Moskal, S. D. Bass, E. Czerwiński, R. Czyżykiewicz, D. Gil, D. Grzonka, T. Johansson, B. Kamys, A. Khoukaz, P. Klaja, W. Krzemień, W. Oelert, B. Rejdych, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Täschner, M. Wolke, P. Wüstner, J. Zdebik, M. Zieliński, W. ZipperThe upper limit of the total cross section for the pn->pneta-prime reaction has been determined near the kinematical threshold in the excess energy range from 0 to 24 MeV. The measurement was performed using the COSY-11 detector setup, a deuteron cluster target, and the proton beam of COSY with a momentum of 3.35 GeV/c. The energy dependence of the upper limit of the cross section was extracted exploiting the Fermi momenta of nucleons inside the deuteron. Comparison of the determined upper limit of the ratio R(eta-prime)=sigma(pn->pneta-prime)/sigma(pp->ppeta-prime) with the corresponding ratio for eta-meson production does not favor the dominance of the N*(1535) resonance in the production process of the eta-prime meson and suggests nonidentical production mechanisms for eta and eta-prime mesons.Measurement of the invariant mass distributions fot he pp->pp eta-prime reaction at excess energy of Q = 16.4 MeVP. Klaja, P. Moskal, E. Czerwiński, R. Czyżykiewicz, A. Deloff, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, K. Nakayama, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Täschner, M. Wolke, J. Zdebik, M. Zieliński, W. ZipperThe proton?proton and proton? invariant mass distributions have been determined for the reaction at an excess energy of . The measurement was carried out using the COSY-11 detector setup and the proton beam of the cooler synchrotron COSY. The shapes of the determined invariant mass distributions are similar to those of the reaction and reveal an enhancement for large relative proton?proton momenta. This result, together with the fact that the proton?? interaction is much stronger that the proton? interaction, excludes the hypothesis that the observed enhancement is caused by the interaction between the proton and the meson.Upper limit of the total cross section for the pn -> pn eta' reactionJ. Klaja, P. Moskal, SD. Bass, E. Czerwinski, R. Czyzykiewicz, D. Gil, D. Grzonka, T. Johansson, B. Kamys, A. Khoukaz, P. Klaja, W. Krzemien, W. Oelert, B. Rejdych, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, M. Zielinski, W. ZipperThe upper limit of the total cross section for the pn -> pn eta' reaction has been determined near the kinematical threshold in the excess energy range from 0 to 24 MeV. The measurement was performed using the COSY-11 detector setup, a deuteron cluster target, and the proton beam of COSY with a momentum of 3.35 GeV/c. The energy dependence of the upper limit of the cross section was extracted exploiting the Fermi momenta of nucleons inside the deuteron. Comparison of the determined upper limit of the ratio R-eta' = sigma(pn -> pn eta')/sigma(pp -> pp eta') with the corresponding ratio for eta-meson production does not favor the dominance of the N*(1535) resonance in the production process of the eta' meson and suggests nonidentical production mechanisms for eta and eta' mesons.Technical Design Report of the Inner Tracker for the KLOE-2 experimentF. Archilli, ..., E. Czerwiński, J. Balwierz, P. Moskal, M. Silarski, J. Zdebik, et al.The technical design report of the Inner Tracker for the KLOE-2 experiment is presentedMeasurement of the invariant mass distributions for the pp -> pp eta ' reaction at excess energy of Q=16.4 MeVP. Klaja, P. Moskal, E. Czerwinski, R. Czyzykiewicz, A. Deloff, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, K. Nakayama, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, J. Zdebik, M. Zielinski, W. ZipperThe proton-proton and proton-eta' invariant mass distributions have been determined for the pp -> pp eta' reaction at an excess energy of Q = 16.4 MeV. The measurement was carried Out using the COSY-11 detector setup and the proton beam of the cooler synchrotron COSY. The shapes of the determined invariant mass distributions are similar to those of the pp -> pp eta reaction and reveal an enhancement for large relative proton-proton momenta. This result, together with the fact that the proton-eta interaction is Much stronger that the proton-eta' interaction, excludes the hypothesis that the observed enhancement is caused by the interaction between the proton and the meson. (C) 2010 Elsevier B.V. All rights reserved.Invariant-mass distributions for the pp -> pp eta reaction at Q=10 MeVP. Moskal, R. Czyzykiewicz, E. Czerwinski, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, P. Klaja, W. Krzemien, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, MJ. Zielinski, W. ZipperProton-proton and proton-eta invariant-mass distributions and the total cross-section for the pp -> pp eta reaction have been determined near the threshold at an excess energy of Q = 10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q = 15.5 MeV and Q = 40 MeV.Invariant mass distributions for the pp->pp eta reaction at Q = 10 MeVP. Moskal, R. Czyżykiewicz, E. Czerwiński, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, P. Klaja, W. Krzemień, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, M. Zieliński, W. ZipperProton-proton and proton-eta invariant-mass distributions and the total cross-section for the pp -> pp h reaction have been determined near the threshold at an excess energy of Q = 10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q = 15.5 MeV and Q = 40 MeV.Generalized Dalitz plot analysis of the near-threshold pp -> ppK(+)K(-) reaction in view of the K+K- final state interactionM. Silarski, P. Moskal, E. Czerwinski, R. Czyzykiewicz, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, P. Klaja, W. Krzemien, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, J. Smyrski, A. Taschner, P. Winter, M. Wolke, P. Wustner, M. Zielinski, W. Zipper, J. ZdebikThe excitation function for the pp -> ppK(+)K(-) reaction revealed a significant enhancement close to threshold that may plausibly be assigned to the influence of the pK(-) and K+K- final-state interactions. In an improved reanalysis of COSY-11 data for the pp -> ppK(+)K(-) reaction at excess energies of Q = 10 and 28 MeV, including the proton-K- interaction, the enhancement is confirmed. Invariant mass distributions for the two- and three-particle subsystems allow us to test at low excess energies the ansatz and parameters for the description of the interaction in the ppK(+)K(-) system as derived from the COSY-ANKE data. Finally, based for the first time on the low-energy K+K- invariant mass distributions and the generalized Dalitz plot analysis, we estimate the scattering length for the K+K- interaction to be vertical bar Re(a(K+K-))vertical bar = 0.5(-0.5)(+4.0) fm and Im(a(K+K-)) = 3.0 +/- 3.0 fm.Generalized Dalitz plot analysis of the near-threshold pp->ppK+K- reaction in view of the K+K- final state interactionM. Silarski, P. Moskal, E. Czerwiński, R. Czyżykiewicz, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, J. Klaja, P. Klaja, W. Krzemień, W. Oelert, J. Ritman, T. Sefzick, M. Siemaszko, J. Smyrski, A. Täschner, P. Winter, M. Wolke, P. Wüstner, M. Zieliński, W. Zipper, J. ZdebikThe excitation function for the pp->ppK+K- reaction revealed a significant enhancement close to threshold which may plausibly be assigned to the influence of the pK- and K+K- final state interactions. In an improved reanalysis of COSY-11 data for the pp-> ppK+K- reaction at excess energies of Q = 10 MeV and 28 MeV including the proton-K- interaction the enhancement is confirmed. Invariant mass distributions for the two- and three-particle subsystems allow to test at low excess energies the ansatz and parameters for the description of the interaction in the ppK+K- system as derived from the COSY-ANKE data. Finally, based for the first time on the low energy K+K- invariant mass distributions and the generalized Dalitz plot analysis, we estimate the scattering length for the K+K- interaction to be |Re(a_K+K-)| = 0.5 + 4.0 -0.5 fm and Im(a_K+K-) = 3.0 +- 3.0 fm.Near-threshold production of the eta meson via the quasi-free pn->pneta reactionP. Moskal, R. Czyżykiewicz, H.-H. Adam, S. D. Bass, A. Budzanowski, E. Czerwiński, D. Gil, D. Grzonka, M. Janusz, L. Jarczyk, T. Johansson, B. Kamys, A. Khoukaz, K. Kilian, P. Klaja, J. Majewski, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, B. Rejdych, J. Ritman, T. Rozek, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taeschner, M. Wolke, P. Wuestner, M. Zieliński, W. Zipper, J. ZdebikTotal cross sections for the quasifree pn->pn? reaction in the range from the kinematical threshold up to 20 MeV excess energy have been determined. At threshold they exceed corresponding cross sections for the pp?pp? reaction by a factor of about 3 in contrast to the factor of 6 established for higher excess energies. To large extent, the observed decrease of the ratio sigma(pn->pn?)/sigma(pp->pp?) toward threshold may be assigned to the different energy dependence of the proton-proton and proton-neutron final-state interactions. The experiment was conducted using a proton beam of the cooler synchrotron COSY and a cluster jet deuteron target. The proton-neutron reactions were tagged by the spectator proton whose momentum was measured for each event. Protons and neutron outgoing from the pn?pn? reaction have been registered by means of the COSY-11 facility, an apparatus dedicated for threshold meson production.Isospin dependence of the eta-prime meson production in nucleon-nucleon collisionsJ. Przerwa, P. Moskal, A. Budzanowski, E. Czerwiński, R. Czyżykiewicz, D. Gil, D. Grzonka, L. Jarczyk, T. Johansson, B. Kamys, A. Khoukaz, P. Klaja, W. Krzemień, W. Oelert, C. Piskor-Ignatowicz, J. Ritman, B. Rejdych, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, M. Zieliński, W. ZipperA comparison of the close-to-threshold total cross section for the eta prime production in pp -> pp eta prime and pn -> pn eta prime reactions constitutes a tool to investigate the eta prime meson structure and the reaction mechanism in the channels of isospin I=0 and I=1 and may provide insight into the flavour-singlet (perhaps also into gluonium) content of the eta prime meson. In this contribution we present preliminary results of measurement of the quasi-free production of the eta prime meson in the proton-neutron collisions conducted using the COSY-11 facility.ISOSPIN DEPENDENCE OF THE eta ' MESON PRODUCTION IN NUCLEON-NUCLEON COLLISIONSJ. Przerwa, P. Moskal, A. Budzanowski, E. Czerwinski, R. Czyzykiewicz, D. Gil, D. Grzonka, L. Jarczyk, T. Johansson, B. Kamys, A. Khoukaz, P. Klaja, W. Krzemien, W. Oelert, C. Piskor-Ignatowicz, J. Ritman, B. Rejdych, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, MJ. Zielinski, W. ZipperA comparison of the close-to-threshold total cross section for the eta' production in pp -> pp eta' and pn -> pn eta' reactions constitutes a tool to investigate the eta' meson structure and the reaction mechanism in the channels of isospin I = 0 and I = 1 and may provide insight into the flavour-singlet (perhaps also into gluonium) content of the eta' meson. In this contribution we present preliminary results of measurement of the quasifree production of the eta' meson in the proton-neutron collisions conducted using the COSY-11 facility.SEARCH FOR THE He-3-eta BOUND STATE AT COSY-11W. Krzemien, J. Smyrski, A. Budzanowski, E. Czerwinski, R. Czyzykiewicz, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, P. Klaja, P. Moskal, W. Oelert, J. Przerwa, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, A. Taschner, M. Wolke, P. Wustner, J. Zdebik, MJ. Zielinski, W. ZipperWe have measured excitation function for dp -> ppp pi(-) reaction near the. production threshold. We observe an enhancement of the counting rate above the threshold which can originate from the production of the. meson in the reaction dp -> He-3 eta and its subsequent absorption on neutron in the 3He nucleus leading to creation of the p pi(-) pair.Search for the 3He-eta bound state at COSY-11W. Krzemien, J. Smyrski, A. Budzanowski, E. Czerwiński, R. Czyżykiewicz, D. Gil, D. Grzonka, L. Jarczyk, B. Kamys, A. Khoukaz, P. Klaja, P. Moskal, W. Oelert, J. Przerwa, J. Ritman, T. Sefzick, M. Siemaszko, M. Silarski, A. Taeschner, M. Wolke, P. Wuestner, J. Zdebik, M. Zieliński, W. ZipperWe have measured excitation function for dp -> ppp_pi- reaction near the eta production threshold. We observe an enhancement of the counting rate above the threshold which can originate from the production of the eta meson in the reaction dp -> 3He eta and its subsequent absorption on neutron in the 3He nucleus leading to creation of the p_pi- pair.Near-threshold production of the eta meson via the quasifree pn -> pn eta reactionP. Moskal, R. Czyzykiewicz, HH. Adam, SD. Bass, A. Budzanowski, E. Czerwinski, D. Gil, D. Grzonka, M. Janusz, L. Jarczyk, T. Johansson, B. Kamys, A. Khoukaz, K. Kilian, P. Klaja, J. Majewski, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, B. Rejdych, J. Ritman, T. Rozek, T. Sefzick, M. Siemaszko, M. Silarski, J. Smyrski, A. Taschner, M. Wolke, P. Wustner, M. Zielinski, W. Zipper, J. ZdebikTotal cross sections for the quasifree pn -> pn eta reaction in the range from the kinematical threshold up to 20 MeV excess energy have been determined. At threshold they exceed corresponding cross sections for the pn -> pn eta reaction by a factor of about 3 in contrast to the factor of 6 established for higher excess energies. To large extent, the observed decrease of the ratio s(pn -> pn eta)/s=sigma(pn -> pn eta) toward threshold may be assigned to the different energy dependence of the proton-proton and proton-neutron final-state interactions. The experiment was conducted using a proton beam of the cooler synchrotron COSY and a cluster jet deuteron target. The proton- neutron reactions were tagged by the spectator proton whose momentum was measured for each event. Protons and neutron outgoing from the pn -> pn eta reaction have been registered by means of the COSY-11 facility, an apparatus dedicated for threshold meson production.Study of the hadronic production of kaon pairs below the threshold for the phi mesonP. Moskal, M. Silarski, A. Budzanowski, E. Czerwinski, R. Czyzykiewic, D. Gil, D. Grzonka, M. Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, P. Klaja, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, B. Rejdych, J. Ritman, T. Sefzick, M. Siemaszko, J. Smyrski, A. Taschner, P. Winter, M. Wolke, P. Wustner, MJ. Zielinski, W. Zipper, J. ZdebikThe near threshold production of K(+)K(-) pairs in proton-proton collisions has been investigated at the cooler synchrotron COSY below and above the threshold for the phi meson using the COSY-11 and ANKE facilities., respectively. The excitation function determined for the pp -> ppK(+)K(-) reaction revealed a statistically significant enhancement close to the threshold which may plausibly be assigned to the influence of the K(-)p interaction. In addition, observed consistently by both groups, a strong enhancement at low values of the ratio of the K(-)p to K(+)p invariant mass distributions shows that the proton interacts much stronger with K(-) than with K(+). In this report we focus on the measurements performed by the COSY-11 collaboration. We explain the experimental method used and present main results of completed analyses as well as a new qualitative elaboration of the ppK(+)K(-) events population on the Goldhaber plot. We conclude with the observation that event densities increase at the region where the influence from the K(+)K(-) interaction is expected.
- Status and perspectives of the KLOE-2 experimentF. Achilli, ..., I. Balwierz, E. Czerwiński, P. Moskal, M. Silarski, J. Zdebik et al.published in: Particle Physics at the Tercentenary of Mikhail Lomonosov: pp. 324-327.The KLOE experiment has acquired an integrated luminosity greater than 2.5 fb?1 at the peak of ?-resonance on the e+e? DA?NE collider in the Frascati National Laboratory (LNF). New data taking with the upgraded detector (KLOE-2) and DA?NE should start in the end of 2011. Main modifications of the detector and new interaction region give a unique possibility to collect about 20 fb?1 in 3 years. The KLOE-2 wide scientific program which contains the experimental study of CP and CPT symmetries, quantum decoherence, ?? physics and search of the dark matter is presented and briefly discussed.
- Recent results on hadron physics at KLOED. Babusci, ..., I. Balwierz - Pytko, E. Czerwiński, A. Gajos, K. Kacprzak, P. Moskal, M. Silarski, W. Wiślicki, J. Zdebik et al.published in: 2013 : QCD and High Energy Interactions : proceedings of the XLVIIIth Rencontres de Moriond La Thuile, Aosta Valley, Italy-MarchOne of the basic motivations of the KLOE and KLOE-2 collaborations is the test of fundamental symmetries and the search for phenomena beyond the Standard Model via the hadronic and leptonic decays of ground-state mesons and via their production in the fusion of virtual gamma quanta exchanged between colliding electrons and positrons. This contribution includes brief description of results of recent analysis of the KLOE data aimed at (i) the search for the dark matter boson, (ii) determination of the hadronic and light-by-light contributions to the g-2 muon anomaly and (iii) tests of QCD anomalies.
- MATRIX-PET: A novel PET detector concept based on large blocks of organic scintillatorsP. Moskal, T. Bednarski, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka - Cupiał, G. Korcyl, W. Krzemień, K. Łojek, W. Migdał, M. Molenda, S. Niedzwiecki, P. Salabura. M. Silarski, A. Słomski, J. Smyrski, Z. Rudy, J. Zdebik, M. Zielińskipublished in: Nuclear Medicine Review 15 (2012) A47-A48Matrix-PET is a novel detector solution for the Positron Emission Tomography. It is one of the two methods which is developed at present at the Jagiellonian University.
- STRIP-PET: Concept of TOF-PET scanner based on polymer scintillator stripsP. Moskal, T. Bednarski, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka - Cupiał, G. Korcyl, W. Krzemień, K. Łojek, W. Migdał, M. Molenda, S. Niedźwiecki, P. Salabura. M. Silarski, A. Słomski, J. Smyrski, Z. Rudy, J. Zdebik, M. Zielińskipublished in: Nuclear Medicine Review 15 (2012) A61-A63The aim of the poster is to present an idea of a new PET scanner based on strips of polymer scintillators arranged in a large acceptance detector system which may allow a simultaneous diagnostic of a large fraction of (or even the whole) human body.
- Polymer Scintillator Detectors for TOF-PET with Large Longitudinal Field of ViewP. Moskal, T. Bednarski, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka - Cupiał, G. Korcyl, W. Krzemień, K. Łojek, W. Migdał, M. Molenda, S. Niedzwiecki, P. Salabura. M. Silarski, A. Słomski, J. Smyrski, Z. Rudy, J. Zdebik, M. Zielińskipublished in: Nuclear Medicine Review 15 (2012) A25-A26In this contribution we present a concept of the large acceptance detector systems based on the organic scintillators which in the future may allow for simultaneous diagnostic of large fraction of the human body.
- U boson searches at KLOEF. Archilli, ..., I. Balwierz, .., E. Czerwiński, ..., P. Moskal, ..., M. Silarski, ..., W. Wiślicki, ..., J. Zdebik, et al.published in: J. Phys. Conf. Ser. 335 (2011) 012067The existence of a secluded gauge sector could explain several puzzling astrophysical observations. This hypothesis can be tested at low energy e+e- colliders such as DAPHNE. Preliminary results obtained with KLOE data and perpectives for the KLOE-2 run, where a larger data sample is expected, are discussed.
- Hadron physics with KLOE-2E. Czerwiński, ..., I. Balwierz, P. Moskal, M. Silarski, J. Zdebik et alpublished in: Nucl. Phys. Proc. Suppl. 207-208:137-140 (2010)In the upcoming month the KLOE-2 data taking campaign will start at the upgraded DAFNE phi-factory of INFN Laboratori Nazionali di Frascati. The main goal is to collect an integrated luminosity of about 20 fb (-1) in 3-4 years in order to refine and extend the KLOE program on both kaon physics and hadron spectroscopy. Here the expected improvements on the results of hadron spectroscopy are presented and briefly discussed.
- Study of the near threshold total cross sesctions for the quasi-free pn -> pn eta-prime reaction with the COSY-11 detector.J. Klaja, P. Moskal, J. Zdebikpublished in: Acta Phys. Polon. Supp. 2 (2009) 31The measurement of the quasi-free production of the eta prime meson has been carried out at the COSY-11 detection setup using a proton beam and a deuteron cluster target. The energy dependence of the cross section is extracted using a fixed proton beam momentum of p_beam=3.35 GeV/c and exploiting the Fermi momenta of nucleons inside deuterons. The data cover a range of centre-of-mass excess energies from 0 to 24 MeV. Due to the low statistics at the present stage only upper limits for the cross sections could be extracted. In this article we focus on the functioning and efficiency determination of the neutron detector.
- Study of the hadronic production of kaon pairs below the threshold for the phi mesonP. Moskal, M. Silarski, A. Budzanowski, E. Czerwiński, R. Czyżykiewicz, D. Gil, D. Grzonka, M. Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, P. Klaja, W. Oelert, C. Piskor-Ignatowicz, J. Przerwa, B. Rejdych, J. Ritman, T. Sefzick, M. Siemaszko, J. Smyrski, A. Taschner, P. Winter, M. Wolke, P. Wustner, M. Zieliński, W. Zipper, J. Zdebikpublished in: Nucl. Phys. Proc. Suppl. 194 (2008) 181-182The near threshold production of K+K- pairs in proton-proton collisions has been investigated at the cooler synchrotron COSY below and above the threshold for the phi meson using the COSY-11 and ANKE facilities, respectively. The excitation function determined for the pp ->ppK+K- reaction revealed a statistically significant enhancement close to the threshold which may plausibly be assigned to the influence of the K-p interaction. In addition, observed consistently by both groups, a strong enhancement at low values of the ratio of the K-p to K+p invariant mass distributions shows that the proton interacts much stronger with K- than with K+. In this report we focus on the measurements performed by the COSY-11 collaboration. We explain the experimental method used and present main results of completed analyses as well as a new qualitative elaboration of the ppK+K- events population on the Goldhaber plot. We conclude with the observation that event densities increase at the region where the influence from the K+K- interaction is expected.
- Matrix-PET: A novel PET detector concept based on large blocks of organic scintillatorsP. Moskal, T. Bednarski, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka-Cupiał, G. Korcyl, W. Krzemień, K. Łojek, W. Migdał, M. Molenda, S. Niedzwiecki, Z. Rudy, P. Salabura, M. Silarski, A. Słomski, J. Smyrski, J. Zdebik, M. ZielińskiPETRAD, Conference on Positron Emission Tomography in Research and Diagnostics 2012
- STRIP-PET: Concept of TOF-PET scanner based on polymer scintillator strips.P. Moskal, T. Bednarski, A. Heczko, M. Kajetanowicz, Ł. Kapłon, A. Kochanowski, G. Konopka - Cupiał, G. Korcyl, W. Krzemień, K. Łojek, W. Migdał, M. Molenda, S. Niedzwiecki, P. Salabura. M. Silarski, A. Słomski, J. Smyrski, Z. Rudy, J. Zdebik, M. ZielińskiPETRAD, Conference on Positron Emission Tomography in Research and Diagnostics 2012
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