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Lovatti G, Nitta M, Javad Safari M, Gianoli C, Pinto M, Dedes G, Zoglauer A, Thirolf PG, Parodi K. Design study of a novel geometrical arrangement for an in-beam small animal positron emission tomography scanner. Phys Med Biol 2023; 68:235005. [PMID: 37906973 DOI: 10.1088/1361-6560/ad0879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 10/31/2023] [Indexed: 11/02/2023]
Abstract
Objective.We designed a geometrical solution for a small animal in-beam positron emission tomography (PET) scanner to be used in the project SIRMIO (Small animal proton irradiator for research in molecular image-guided radiation-oncology). The system is based on 56 scintillator blocks of pixelated LYSO crystals. The crystals are arranged providing a pyramidal-step shape to optimize the geometrical coverage in a spherical configuration.Approach.Different arrangements have been simulated and compared in terms of spatial resolution and sensitivity. The chosen setup enables us to reach a good trade-off between a solid angle coverage and sufficient available space for the integration of additional components of the first design prototype of the SIRMIO platform. The possibility of moving the mouse holder inside the PET scanner furthermore allows for achieving the optimum placement of the irradiation area for all the possible tumor positions in the body of the mouse. The work also includes a study of the scintillator material where LYSO and GAGG are compared with a focus on the random coincidence noise due to the natural radioactivity of Lutetium in LYSO, justifying the choice of LYSO for the development of the final system.Main results.The best imaging performance can be achieved with a sub-millimeter spatial resolution and sensitivity of 10% in the center of the scanner, as verified in thorough simulations of point sources. The simulation of realistic irradiation scenarios of proton beams in PMMA targets with/without air gaps indicates the ability of the proposed PET system to detect range shifts down to 0.2 mm.Significance.The presented results support the choice of the identified optimal design for a novel spherical in-beam PET scanner which is currently under commissioning for application to small animal proton and light ion irradiation, and which might find also application, e.g. for biological image-guidance in x-ray irradiation.
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Affiliation(s)
- Giulio Lovatti
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Munetaka Nitta
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Mohammad Javad Safari
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Chiara Gianoli
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Marco Pinto
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Georgios Dedes
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Andreas Zoglauer
- Space Sciences Laboratory, University of California, Berkeley, United States of America
| | - Peter G Thirolf
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
| | - Katia Parodi
- Department of Medical Physics, Ludwig-Maximilians-Universität München (LMU), Munich, Germany
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Valladares C, Barrio J, Freire M, Cucarella N, Lamprou E, Miyaoka RS, Hunter WCJ, Harrison R, Gonzalez AJ. Timing, Energy, and Spatial Characterization of Highly Sampled Monolithic PET Detectors with Different Thicknesses. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2023; 7:704-711. [PMID: 38524735 PMCID: PMC10957137 DOI: 10.1109/trpms.2023.3280711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
The HyPET project proposes a hybrid dedicated TOF-PET for prostate imaging, with pixelated detector blocks in the front layer and monolithic blocks in the back layer. In this work, four detector configurations have been experimentally evaluated for the rear detector layer. The detector configuration consists of LYSO monolithic blocks with the same size (25.4 mm × 25.4 mm) but different thicknesses (5, 7.5, 10, and 15 mm) coupled to the same SiPM array. Each detector configuration has been experimentally characterized in terms of time, energy and spatial resolution by scanning the crystal surface using a fan beam in steps of 0.25 mm. Regarding spatial resolution, the interaction position was estimated using a Neural Network technique. All resolutions except energy, which remains nearly constant at 17% for all cases, show better values for the 5 mm detector thickness. We have achieved spatial resolution values of FWHM of 1.02 ± 0.10, 1.19 ± 0.13, 1.53 ± 0.17, 2.33 ± 0.55 mm, for the 5, 7.5, 10, and 15 mm blocks, respectively. The detector time resolution obtained was 275 ± 26, 291 ± 21, 344 ± 48, and 433 ± 45 ps respectively, using the energy weighted average method for the time stamps.
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Affiliation(s)
- Celia Valladares
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
| | - John Barrio
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
| | - Marta Freire
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
| | - Neus Cucarella
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
| | - Efthymios Lamprou
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
| | - Robert S Miyaoka
- University of Washington Department of Radiology, Seattle, WA 98195 USA
| | | | - Robert Harrison
- University of Washington Department of Radiology, Seattle, WA 98195 USA
| | - Antonio J Gonzalez
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro mixto CSIC - Universitat Politècnica de València, 46022 Valencia, Spain
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3
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Konstantinou G, Latella R, Moliner L, Zhang L, Benlloch JM, Gonzalez AJ, Lecoq P. A proof-of-concept of cross-luminescent metascintillators: testing results on a BGO:BaF 2metapixel. Phys Med Biol 2023; 68. [PMID: 36595320 DOI: 10.1088/1361-6560/acac5f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Objective: Time-of-flight positron emission tomography (PET) is the next frontier in improving the effective sensitivity. To achieve superior timing for time-of-flight PET, combined with high detection efficiency and cost-effectiveness, we have studied the applicability of BaF2 in metascintillators driven by the timing of cross-luminescence photon production.Approach: Based on previous simulation studies of energy sharing and analytic multi-exponential scintillation pulse, as well as sensitivity characteristics, we have experimentally tested a pixel of 3 × 3 × 15 mm3 based on 300μm BGO and 300μm BaF2 layers. To harness the deep ultraviolet cross-luminescent light component, which carries improved timing, we use the FBK VUV SiPM. Metascintillator energy sharing is addressed through a double integration approach.Main results: We reach an energy resolution of 22%, comparable to an 18% resolution of simple BGO pixels using the same readout, through the optimized use of the integrals of the metascintillator pulse in energy sharing calculation. We measure the energy sharing extent of each pulse with a resolution of 25% and demonstrate that experimental and simulation results agree well. Based on the energy sharing, a timewalk correction is applied, exhibiting significant improvements for both the coincidence time resolution (CTR) and the shape of the timing histogram. We reach 242 ps CTR for the entire photopeak, while for a subset of 13% of the most shared events, the CTR value improves to 108 ps, comparable to the 3 × 3 × 5 mm3 LYSO:Ce:Ca reference crystal.Significance: While we are considering different ways to improve further these results, this proof-of-concept demonstrates the applicability of cross-luminescence for metascintillator designs through the application of VUV compatible SiPM coupling, and easily implementable digital algorithms. This is the first test of BaF2-based metascintillators of sufficient stoppng power to be included in a PET scanner, demonstrating the industrial applicability of such cross-luminescent metascintillators.
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Affiliation(s)
- G Konstantinou
- Multiwave Metacrystal S.A., 34 Route de la Galaise, 1228, Geneva, Switzerland.,Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - R Latella
- Multiwave Metacrystal S.A., 34 Route de la Galaise, 1228, Geneva, Switzerland.,Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - L Moliner
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - L Zhang
- Multiwave Metacrystal S.A., 34 Route de la Galaise, 1228, Geneva, Switzerland
| | - J M Benlloch
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - A J Gonzalez
- Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
| | - P Lecoq
- Multiwave Metacrystal S.A., 34 Route de la Galaise, 1228, Geneva, Switzerland.,Instituto de Instrumentación para Imagen Molecular (I3M), Centro Mixto CSIC-Universitat Politècnica de València, 46022 Valencia, Spain
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Zhang H, Zhou R, Yao R, Yang C, Xu S, Shu Y, Jiang B, Liu L. A study on a nonlinear least-squares fitting method for 3D positioning of gamma rays based on monolithic crystal and SiPM array. RADIATION DETECTION TECHNOLOGY AND METHODS 2022. [DOI: 10.1007/s41605-022-00333-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Yoshida E, Obata F, Kamada K, Yoshikawa A, Yamaya T. Development of crosshair light sharing PET detector with TOF and DOI capabilities using fast LGSO scintillator. Phys Med Biol 2021; 66. [PMID: 34644694 DOI: 10.1088/1361-6560/ac2f8b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 10/13/2021] [Indexed: 11/12/2022]
Abstract
Objective.Time-of-flight (TOF) and depth-of-interaction (DOI) are well recognized as important information to improve PET image quality. Since such information types are not correlated, many TOF-DOI detectors have been developed but there are only a few reports of high-resolution detectors (e.g. 1.5 mm resolution) for brain PET systems. Based on the DOI detector, which enables single-ended readout by optically coupling a pair of crystals and having a loop structure, we have developed the crosshair light sharing (CLS) PET detector that optically couples the four-loop structure, consisting of quadrisected crystals comparable in size to a photo-sensor, to four photo-sensors in close proximity arranged in a windmill shape. Even as a high-resolution detector, the CLS PET detector could obtain both TOF and DOI information. The coincidence resolving time (CRT) of the CLS PET detector needs to be further improved, however, for application to the brain PET system. Recently, a fast LGSO crystal was developed which has advantages in detection efficiency and CRT compared to the GFAG crystal. In this work, we developed the CLS PET detector using the fast LGSO crystal for the TOF-DOI brain PET system.Approach.The crystals were each 1.45 × 1.45 × 15 mm3and all surfaces were chemically etched. The CLS PET detector consisted of a 14 × 14 crystal array optically coupled to an 8 × 8 MPPC array.Main results.The fast LGSO array provided 10.1% energy resolution at 511 keV, 4.7 mm DOI resolution at 662 keV, and 293 ps CRT with the energy window of 440-620 keV.Significance.The developed CLS PET detector has 290% higher coincidence sensitivity, 30% better energy resolution, and 32% better time resolution compared to our previous CLS PET detector.
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Affiliation(s)
- Eiji Yoshida
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Fujino Obata
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
| | - Kei Kamada
- New Industry Creation Hatchery Center, Tohoku University, Japan
| | - Akira Yoshikawa
- New Industry Creation Hatchery Center, Tohoku University, Japan.,Institute for Materials Research, Tohoku University, Japan
| | - Taiga Yamaya
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
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6
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Kang HG, Tashima H, Nishikido F, Akamatsu G, Wakizaka H, Higuchi M, Yamaya T. Initial results of a mouse brain PET insert with a staggered 3-layer DOI detector. Phys Med Biol 2021; 66. [PMID: 34666328 DOI: 10.1088/1361-6560/ac311c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 10/19/2021] [Indexed: 11/11/2022]
Abstract
Objective.Small animal positron emission tomography (PET) requires a submillimeter resolution for better quantification of radiopharmaceuticals. On the other hand, depth-of-interaction (DOI) information is essential to preserve the spatial resolution while maintaining the sensitivity. Recently, we developed a staggered 3-layer DOI detector with 1 mm crystal pitch and 15 mm total crystal thickness, but we did not demonstrate the imaging performance of the DOI detector with full ring geometry. In this study we present initial imaging results obtained for a mouse brain PET prototype developed with the staggered 3-layer DOI detector.Approach.The prototype had 53 mm inner diameter and 11 mm axial field-of-view. The PET scanner consisted of 16 DOI detectors each of which had a staggered 3-layer LYSO crystal array (4/4/7 mm) coupled to a 4 × 4 silicon photomultiplier array. The physical performance was evaluated in terms of the NEMA NU 4 2008 protocol.Main Results.The measured spatial resolutions at the center and 15 mm radial offset were 0.67 mm and 1.56 mm for filtered-back-projection, respectively. The peak absolute sensitivity of 0.74% was obtained with an energy window of 400-600 keV. The resolution phantom imaging results show the clear identification of a submillimetric rod pattern with the ordered-subset expectation maximization algorithm. The inter-crystal scatter rejection using a narrow energy window could enhance the resolvability of a 0.75 mm rod significantly.Significance.In an animal imaging experiment, the detailed mouse brain structures such as cortex and thalamus were clearly identified with high contrast. In conclusion, we successfully developed the mouse brain PET insert prototype with a staggered 3-layer DOI detector.
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Affiliation(s)
- Han Gyu Kang
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Hideaki Tashima
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Fumihiko Nishikido
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Go Akamatsu
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Hidekazu Wakizaka
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Makoto Higuchi
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
| | - Taiga Yamaya
- National Institutes for Quantum Science and Technology (QST), 4-9-1, Anagawa, Inage-ku, Chiba, Japan
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7
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Boscolo D, Kostyleva D, Safari MJ, Anagnostatou V, Äystö J, Bagchi S, Binder T, Dedes G, Dendooven P, Dickel T, Drozd V, Franczack B, Geissel H, Gianoli C, Graeff C, Grahn T, Greiner F, Haettner E, Haghani R, Harakeh MN, Horst F, Hornung C, Hucka JP, Kalantar-Nayestanaki N, Kazantseva E, Kindler B, Knöbel R, Kuzminchuk-Feuerstein N, Lommel B, Mukha I, Nociforo C, Ishikawa S, Lovatti G, Nitta M, Ozoemelam I, Pietri S, Plaß WR, Prochazka A, Purushothaman S, Reidel CA, Roesch H, Schirru F, Schuy C, Sokol O, Steinsberger T, Tanaka YK, Tanihata I, Thirolf P, Tinganelli W, Voss B, Weber U, Weick H, Winfield JS, Winkler M, Zhao J, Scheidenberger C, Parodi K, Durante M. Radioactive Beams for Image-Guided Particle Therapy: The BARB Experiment at GSI. Front Oncol 2021; 11:737050. [PMID: 34504803 PMCID: PMC8422860 DOI: 10.3389/fonc.2021.737050] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/04/2021] [Indexed: 12/11/2022] Open
Abstract
Several techniques are under development for image-guidance in particle therapy. Positron (β+) emission tomography (PET) is in use since many years, because accelerated ions generate positron-emitting isotopes by nuclear fragmentation in the human body. In heavy ion therapy, a major part of the PET signals is produced by β+-emitters generated via projectile fragmentation. A much higher intensity for the PET signal can be obtained using β+-radioactive beams directly for treatment. This idea has always been hampered by the low intensity of the secondary beams, produced by fragmentation of the primary, stable beams. With the intensity upgrade of the SIS-18 synchrotron and the isotopic separation with the fragment separator FRS in the FAIR-phase-0 in Darmstadt, it is now possible to reach radioactive ion beams with sufficient intensity to treat a tumor in small animals. This was the motivation of the BARB (Biomedical Applications of Radioactive ion Beams) experiment that is ongoing at GSI in Darmstadt. This paper will present the plans and instruments developed by the BARB collaboration for testing the use of radioactive beams in cancer therapy.
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Affiliation(s)
- Daria Boscolo
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Daria Kostyleva
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | | | | | - Juha Äystö
- University of Jyväskylä, Jyväskylä, Finland.,Helsinki Institute of Physics, Helsinki, Finland
| | | | - Tim Binder
- Ludwig-Maximilians-Universität München, Munich, Germany
| | | | | | - Timo Dickel
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Vasyl Drozd
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,University of Groningen, Groningen, Netherlands
| | | | - Hans Geissel
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Justus-Liebig-Universität Gießen, Gießen, Germany
| | | | - Christian Graeff
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Tuomas Grahn
- University of Jyväskylä, Jyväskylä, Finland.,Helsinki Institute of Physics, Helsinki, Finland
| | - Florian Greiner
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Emma Haettner
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | | | | | - Felix Horst
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Christine Hornung
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Technische Universität Darmstadt, Darmstadt, Germany
| | - Jan-Paul Hucka
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Technische Universität Darmstadt, Darmstadt, Germany
| | | | - Erika Kazantseva
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Birgit Kindler
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Ronja Knöbel
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | | | - Bettina Lommel
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Ivan Mukha
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Chiara Nociforo
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | | | | | | | | | - Stephane Pietri
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Wolfgang R Plaß
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Justus-Liebig-Universität Gießen, Gießen, Germany
| | | | | | | | - Heidi Roesch
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Technische Universität Darmstadt, Darmstadt, Germany
| | - Fabio Schirru
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Christoph Schuy
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Olga Sokol
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Timo Steinsberger
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Technische Universität Darmstadt, Darmstadt, Germany
| | | | - Isao Tanihata
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan.,Peking University, Beijing, China.,Institute of Modern Physics, Lanzhou, China
| | - Peter Thirolf
- Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Bernd Voss
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Uli Weber
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Helmut Weick
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - John S Winfield
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Martin Winkler
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Jianwei Zhao
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Peking University, Beijing, China
| | - Christoph Scheidenberger
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Justus-Liebig-Universität Gießen, Gießen, Germany
| | - Katia Parodi
- Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marco Durante
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Technische Universität Darmstadt, Darmstadt, Germany
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