First Positronium Lifetime Imaging using 52Mn and 55Co with a plastic-based PET scanner
Manish Das, Sushil Sharma, Ermias Yitayew Beyene, Aleksander Bilewicz, Jarosław Choiński, Neha Chug, Catalina Curceanu, Eryk Czerwiński, Jakub Hajduga, Sharareh Jalali, Krzysztof Kacprzak, Tevfik Kaplanoglu, Łukasz Kapłon, Kamila Kasperska, Aleksander Khreptak, Grzegorz Korcyl, Tomasz Kozik, Karol Kubat, Deepak Kumar, Sumit Kumar Kundu, Anoop Kunimmal Venadan, Edward Lisowski, Filip Lisowski, Justyna Medrala-Sowa, Simbarashe Moyo, Wiktor Mryka, Szymon Niedźwiecki, Anand Pandey, Piyush Pandey, Szymon Parzych, Alessio Porcelli, Bartłomiej Rachwał, Martin Rädler, Narendra Rathod, Noman Razzaq, Axel Rominger, Kuangyu Shi, Magdalena Skurzok, Maciej Słotwiński, Anna Stolarz, Tomasz Szumlak, Pooja Tanty, Keyvan Tayefi Ardebili, Satyam Tiwari, Kavya Valsan Eliyan, Rafał Walczak, Ewa Ł. Stępień, Paweł Moskal

abstract
This study demonstrates applicability of 52Mn and 55Co radionuclides for positronium imaging. Positronium Lifetime Imaging
(PLI) extends positron emission tomography by using the lifetime of positronium atoms as a probe of tissue molecular
architecture. However, its practical use requires ?+ emitters that also provide an additional prompt ? ray to mark the positron creation time. In this work, we report the first PLI measurements performed with 52Mn and 55Co using the modular J-PET. Four samples were studied in each experiment: two Certified Reference Materials (polycarbonate and fused silica) and two
human tissues (cardiac myxoma and adipose). The selection of PLI events was based on the registration of two 511 keV
annihilation photons and one prompt gamma in triple coincidence. From the resulting lifetime spectra we extracted the mean
ortho-positronium lifetime ?oPs and the mean positron lifetime ?Tmean for each sample. The measured values of ?oPs in
polycarbonate using both isotopes matches well with the certified reference values. Furthermore, 55Co reproduced identical
results for fused-silica measurements at their respective uncertainty levels. In contrast, measurements with 52Mn in fused silica show a minor deviation, which could be caused by the Parafilm spacer. In myxoma and adipose tissue, the reduced ?oPs values are mainly linked to the long storage history of the samples rather than to the choice of isotope. Comparing peak-to-background ratios and spectral purity, 55Co provides cleaner PLI data under the same experimental conditions. Although 52Mn offers a longer half-life and a multi gamma cascade enhancing ?+ + ? coincidences, but at the expense of higher background. In this study, we demonstrate that the applied selection criteria on the data measured with the modular J-PET can be used for PLI studies even with radionuclides with complex decay patterns.
Studies of CPT symmetry in positronium decays with 192 plastic strip J-PET detector
N. Chug, S. D. Bass, E. Y. Beyene, C. Curceanu, E. Czerwiński, M. Das, K. V. Eliyan, M. Gorgol, J. Hajduga, S. Jalali, B. Jasińska, K. Kacprzak, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, A. Kierys, G. Korcyl, T. Kozik, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, E. Pérez del Río, A. Porcelli, B. Rachwał, M. Rädler, A. Sienkiewicz, S. Sharma, M. Skurzok, E. Ł. Stępień, T. Szumlak, P. Tanty, K. Tayefi Ardebili, S. Tiwari, P. Moskal

abstract
Accepted in Phys. Rev. D.
Mirror Matter: Towards Precise Measurement of Ortho-Positronium Lifetime
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal

abstract
Positronium (Ps), an exotic atom composed of an electron and a positron, provides a unique system for testing fundamental physics and verifying quantum electrodynamic predictions. At Jagiellonian University, the J-PET detector enables high-precision studies of positronium decays and the search for dark matter. This work focuses on mirror matter, a hypothetical dark matter candidate, by comparing measured o-Ps lifetimes with quantum electrodynamic predictions to probe potential deviations.
Quality control of plastic scintillators for the total-body J-PET scanner
Ł. Kapłon, E. Beyene, N. Chug, C. Curceanu, E. Czerwiński, M. Das, K. Eliyan, K. Kacprzak, T. Kaplanoglu, G. Korcyl, K. Kubat, D. Kumar, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, G. Moskal, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, E. Pérez del Rio, S. Sharma, M. Skurzok, P. Tanty, K. Tayefi, A. Venadan, E. Stępień and P. Moskal

abstract
The construction of the total-body Jagiellonian positron emission tomography scanner requires component verification before detector assembly. The purpose of this research is to verify the quality of BC-408 plastic scintillators with dimensions 6 mm × 30 mm × 330 mm. The scintillators were inspected for optical and mechanical defects and all dimensions were measured. Scratches, mechanically damaged corners and edges, as well as encapsulated dust and fibers within the scintillators, were identified under ceiling lamp illumination. Line defects on the as-cast surfaces were easily visible in a plane polariscope setup consisting of crossed horizontal and vertical polarizer foils. The transmittance at the wavelength of maximum emission through 6 mm thick scintillator samples and the technical attenuation length along 330 mm long scintillator samples were measured on a linear CCD array spectrometer for randomly selected scintillators from each delivered batch. Selected properties of the emission spectra, such as their FWHM and the values of the emission maxima as a function of the distance between the excitation point and the spectrometer fiber, were measured. Additionally, the scintillators optical homogeneity was measured on a light transfer setup consisting of an LED and photodiode matrix. The majority of the obtained plastic scintillators meets the transparency criteria and falls within the dimensional tolerances.
muPPET: Investigating the Muon Puzzle with J-PET Detectors
A. Porcelli, K. Valsan Eliyan, G. Moskal, N. Nasrin Protiti, D. L. Sirghi, E. Yitayew Beyene, N. Chug, C. Curceanu, E. Czerwiński, M. Das, M. Gorgol, J. Hajduga, S. Jalali, B. Jasińska, K. Kacprzak, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, T. Kozik, D. Kumar, K. Kubat, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, W. Mryka, S. Moyo, S. Niedźwiecki, S. Parzych, P. Pandey, E. Perez del Rio, B. Rachwał, M. Rädler, S. Sharma, M. Skurzok, E. Ł. Stępień, T. Szumlak, P. Tanty, K. Tayefi Ardebili, S. Tiwari, and P. Moskal

abstract
The muPPET [muon Probe with J-PET] project aims to investigate the Muon
Puzzle seen in cosmic ray air showers. This puzzle arises from the observation of a significantly
larger number of muons on Earth's surface than that predicted by the current
theoretical models. The investigated hypothesis is based on recently observed asymmetries
in the parameters for the strong interaction cross-section and trajectory of an outgoing particle
due to projectile-target polarization. The measurements require detailed information
about muons at the ground level, including their track and charge distributions. To achieve
this, the two PET scanners developed at the Jagiellonian University in Krakow (Poland),
the J-PET detectors, will be employed, taking advantage of their well-known resolution
and convenient location for detecting muons that reach long depths in the atmosphere.
One station will be used as a muon tracker, while the second will reconstruct the core of
the air shower. In parallel, the existing hadronic interaction models will be modified and
fine-tuned based on the experimental results. In this work, we present the conceptualization
and preliminary designs of muPPET.
Development of correction techniques for a J-PET scanner
M. Das, R. Bayerlein, S. Sharma, S. Parzych, S. Niedźwiecki, R. Badawi, E. Yitayew Beyene, N. Chug, C. Curceanu, E. Czerwiński, K. Valsan Eliyan, B. Głowa, A. Hubalewska-Dydejczyk, K. Kacprzak, T. Kaplanoglu, K. Kasperska, G. Korcyl, A. Khreptak, K. Kubat, D. Kumar, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, M. Opalińska, P. Pandey, M. Rädler, M. Skurzok, A. Sowa-Staszczak, B. A. Spencer, P. Tanty, K. Tayefi Ardebili, A. Kunimmal Venadan, E. Stępień, P. Moskal

abstract
Objective: Positron Emission Tomography (PET) is a widely used medical imaging technique that allows for non-invasive imaging of metabolic processes. However, traditional PET scanners rely on costly inorganic scintillators, which limit their accessibility ? especially in light of emerging long axial field-of-view devices. The modular J-PET scanner, an innovative alternative, uses 50-cm long plastic scintillator strips, offering a cost-effective and modular solution. In this study, we develop and assess the PET data correction techniques required for quantitative image reconstruction. Methods: We present methods for attenuation correction, random coincidence correction using the Delayed Time Window (DTW) technique, and scatter correction based on Monte Carlo simulations. Phantom studies using the NEMA IQ phantom were performed to qualitatively evaluate these corrections. Results: The results demonstrate that our implemented corrections for attenuation, randoms, and scattered coincidences successfully improve the uniformity of tracer distribution in homogenous volumes and significantly reduce undesired activity in cold regions. Despite limitations in sensitivity and axial resolution, the applied correction techniques effectively enhance image quality, providing promising results for future applications. Conclusions: These findings highlight the potential of the modular J-PET system to offer affordable PET imaging and to pave the way towards a total-body PET scanner based on plastic scintillators. Future work will focus on quantitative validation and the implementation of these corrections for human subject imaging.
First Experimental Demonstration of Positronium Lifetime Imaging with 44Sc Using the J-PET Scanner
M. Das, S. Sharma, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P.D. Río, M. Rädler, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E.Ł. Stępień, P. Moskal
published in: 2025 IEEE Nuclear Science Symposium (NSS), Medical Imaging Conference (MIC) and Room Temperature Semiconductor Detector Conference (RTSD)
Positronium lifetime imaging (PLI) [1], an extension of PET, provides insight into the submolecular properties of tissues by imaging the lifetime of the positronium atom [2]. Currently, the method is under rapid development as regards reconstruction [3], [4] and detection systems [5], [6]. The first studies with the J-PET scanner using 68Ga have demonstrated the feasibility of this technique in human subjects [6]. However, the Ga68 isotope has limitations due to its low yield of de-excitation photons necessary for positronium lifetime estimation. In this context, 44Sc emerges as a promising candidate for PLI [7], offering a clinically optimal half-life of 3.97 hours and a high deexcitation photon yield of 94.3 % with an energy of 1157 keV. In this work, we report the results of the successful demonstration of PLI with 44 Sc using the Modular J-PET tomograph, featuring triggerless data acquisition that enables simultaneous multiphoton detection [8]. 44Sc was produced at the Heavy Ion Laboratory in Warsaw and transported to Jagiellonian University in Kraków. A NEMA IQ phantom with six spheres was used. The three largest spheres were filled with 44Sc, and the three smallest with 18 F, both diluted with water, having an initial activity concentration ratio of 1:3. Event selection was based on the simultaneous detection of two 511 keV photons and one de-excitation photon, enabling reconstruction of images of the mean positronium lifetime [2], [6]. The measured mean o-Ps lifetime shows good agreement with previously reported values in water [9]. This study presents the first-ever demonstration of PLI with 44 Sc, marking a significant advancement and opening new possibilities for developing PLI for clinical applications.
Mirror Matter in Ortho-positronium Decay Searches Using the J-PET Detector
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal
published in: Acta Phys. Pol. B Proc. Suppl. 17 (2024) 7-A8
Positronium (Ps), governed by Quantum Electrodynamics (QED), provides a rich domain for exploring fundamental physics. Monte Carlo simulations of its decay provide insights into various aspects of particle physics. The development of J-PET, an innovative tomography system at the Jagiellonian University using high-resolution scintillator detectors, facilitates interdisciplinary studies encompassing fundamental physics tests, medical research, and quantum entanglement measurements but also enhances our capacity to investigate positronium decays in pursuit of potential dark matter (DM) candidates, a lingering enigma within the current Standard Model (SM) framework. In our research, we employ the J-PET detector to study ortho-positronium (o-Ps) decays as a part of our ongoing quest for the discovery of DM. Our primary goal is to explore mirror matter, which seeks to restore parity invariance and is proposed as a candidate for the Universe?s DM. Our study aims to push the boundaries of precision measurement in the decay width of o-Ps to three gamma quanta, contributing to our understanding of the elusive nature of dark matter. The article presents the preliminary lifetime distribution of o-Ps as a search for mirror matter obtained from data collected during a portion of a long-term measurement conducted with the J-PET detector in 2020. The long-term aim of the study is to achieve 10^-6 lifetime sensitivity.
Feasibility studies of dark photon searches with the J-PET detector
J. Mędrala-Sowa, E. Perez del Rio, W. Krzemień
published in: Acta Phys. Pol. B Proc. Suppl. 17 (2024) 1-A5
The positronium, a bound state of electron and positron, is a unique system to perform highly precise tests, due to no hadronic background and precise Quantum Electrodynamics (QED) predictions. Being a system of lepton and antilepton, its properties are precisely described by QED in the Standard Model (SM). The final events topology can be simulated using Monte Carlo techniques. The J-PET detector is a multi-purpose, large acceptance system that is very well-suitable to the studies of positronium decay due to its excellent angular (1?) and timing resolutions. We present preliminary results on the feasibility of searching for Dark Matter (DM) candidates in the decay o-Ps -> invisible with the J-PET, which is wellsuited for the detection of positronium-decay products. Toy Monte Carlo simulations have been prepared to incorporate DM decay models to the oPs decay expectations in order to assess the detector capabilities to search for such an elusive component of our Universe.
First Experimental Demonstration of Positronium Lifetime Imaging with 44Sc Using the J-PET Scanner
M. Das, S. Sharma, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, K. Kasperska, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P.D. Río, M. Rädler, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E.Ł. Stępień, P. Moskal
2025 IEEE Nuclear Science Symposium (NSS), Medical Imaging Conference (MIC) and Room Temperature Semiconductor Detector Conference (RTSD), Yokohama, Japan (1-8 November 2025))
Simulation studies of a brain PET insert for the total body J-PET tomograph
M. Rädler, E. Y. Beyene, A. Bilewicz, J. Choiński, N. Chug, C. Curceanu, E. Czerwiński, M. Das, J. Hajduga, S. Jalali, T. Kaplanoglu, Ł. Kapłon, A. Khreptak, G. Korcyl, K. Kubat, D. Kumar, A. Kunimmal Venadan, E. Lisowski, F. Lisowski, J. Mędrala-Sowa, S. Moyo, W. Mryka, S. Niedźwiecki, P. Pandey, S. Parzych, A. Porcelli, B. Rachwał, E. P. d. Río, S. Sharma, M. Skurzok, A. Stolarz, T. Szumlak, S. Tiwari, P. Tanty, K. Tayefi Ardebili, K. Valsan Eliyan, R. Walczak, E. Ł. Stępień, P. Moskal
IEEE NSS MIC RTSD in Yokohama
Mirror matter: towards a precise measurement of ortho-positronium lifetime
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal
2nd Symposium on New Trends in Nuclear and Medical Physics, Krakow, Poland (24-26 September 2025)
Probing Mirror Matter via Ortho-Positronium Decays with J-PET detector
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal
Mirror Matter in Positronium Decay Searches with the J-PET Detector
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal
EXA/LEAP 2024, Vienna, Austria (25-30 August 2024)
Mirror Matter in Ortho-Positronium Decay Searches using the J-PET Detector
J. Mędrala-Sowa, E. Perez del Rio, P. Moskal
5th Jagiellonian Symposium on Advances in Particle Physics and Medicine in Kraków
Feasibility studies of Dark Photon searches with the J-PET detector
J. Mędrala-Sowa, E. Perez del Rio, W. Krzemień
Symposium on new trends in Nuclear and Medical Physics