Precision Measurement of the Helium Flux in Primary Cosmic Rays of Rigidities 1.9 GV to 3 TV with the Alpha Magnetic Spectrometer on the International Space Station

Aguilar, M.; Aisa, D.; Alpat, B.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bindi, V.; Bizzaglia, S.; Bizzarri, M.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Borsini, S.; Boschini, M. J.; Bourquin, M.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Castellini, G.; Cernuda, I.; Cerreta, D.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, G. M.; Chen, H.; Chen, H. S.; Cheng, L.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Gil, E. Cortina; Coste, B.; Creus, W.; Crispoltoni, M.; Cui, Z.; Dai, Y. M.; Delgado, C.; Della Torre, S.; Demirkoz, M. B.; Derome, L.; Di Falco, S.; Di Masso, L.; Dimiccoli, F.; Diaz, C.; von Doetinchem, P.; Donnini, F.; Duranti, M.; D'Urso, D.; Egorov, A.; Eline, A.; Eppling, F. J.; Eronen, T.; Fan, Y. Y.; Farnesini, L.; Feng, J.; Fiandrini, E.; Fiasson, A.; Finch, E.; Fisher, P.; Formato, V.; Galaktionov, Y.; Gallucci, G.; Garcia, B.; Garcia-Lopez, R.; Gargiulo, C.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Giovacchini, F.; Goglov, P.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guandalini, C.; Guerri, I.; Guo, K. H.; Haas, D.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hsieh, T. H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Korkmaz, M. A.; Kossakowski, R.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Li, H. L.; Li, J. Q.; Li, Q.; Li, T. X.; Li, W.; Li, Y.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, H.; Liu, Hu; Lolli, M.; Lomtadze, T.; Lu, M. J.; Lu, S. Q.; Lu, Y. S.; Luebelsmeyer, K.; Luo, F.; Luo, J. Z.; Lv, S. S.; Majka, R.; Mana, C.; Marin, J.; Martin, T.; Martinez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Mueller, M.; Nelson, T.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Obermeier, A.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Papi, A.; Pauluzzi, M.; Pedreschi, E.; Pensotti, S.; Pereira, R.; Picot-Clemente, N.; Pilo, F.; Piluso, A.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Putze, A.; Quadrani, L.; Qi, X. M.; Qin, X.; Qu, Z. Y.; Raeihae, T.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodriguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Schael, S.; Schmidt, S. M.; von Dratzig, A. Schulz; Schwering, G.; Scolieri, G.; Seo, E. S.; Shan, B. S.; Shan, Y. H.; Shi, J. Y.; Shi, X. Y.; Shi, Y. M.; Siedenburg, T.; Son, D.; Song, J. W.; Spada, F.; Spinella, F.; Sun, W.; Sun, W. H.; Tacconi, M.; Tang, C. P.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Tuerkoglu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vaurynovich, S.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Vitale, V.; Vitillo, S.; Wang, L. Q.; Wang, N. H.; Wang, Q. L.; Wang, R. S.; Wang, X.; Wang, Z. X.; Weng, Z. L.; Whitman, K.; Wienkenhoever, J.; Willenbrock, M.; Wu, H.; Wu, X.; Xia, X.; Xie, M.; Xie, S.; Xiong, R. Q.; Xu, N. S.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Yang, Y.; Ye, Q. H.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, C.; Zhang, J. H.; Zhang, M. T.; Zhang, S. D.; Zhang, S. W.; Zhang, X. B.; Zhang, Z.; Zheng, Z. M.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; Collaboration, AMS

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Author(s): Show less -	Aguilar, M. ^[1] ; Aisa, D. ^{[2, 3]} ; Alpat, B. ^[3] ; Alvino, A. ^[3] ; Ambrosi, G. ^[3] ; Andeen, K. ^[4] ; Arruda, L. ^[5] ; Attig, N. ^{[6, 7]} ; Azzarello, P. ^[8] ; Bachlechner, A. ^{[9, 10, 11]} ; Barao, F. ^[5] ; Barrau, A. ^[12] ; Barrin, L. ^[13] ; Bartoloni, A. ^[14] ; Basara, L. ^[15] ; Battarbee, M. ^[16] ; Battiston, R. ^{[17, 18, 15]} ; Bazo, J. ^[3] ; Becker, U. ^[9] ; Behlmann, M. ^[9] ; Beischer, B. ^{[10, 11]} ; Berdugo, J. ^[1] ; Bertucci, B. ^{[2, 3]} ; Bindi, V. ^[19] ; Bizzaglia, S. ^[3] ; Bizzarri, M. ^{[2, 3]} ; Boella, G. ^{[20, 21]} ; de Boer, W. ^[4] ; Bollweg, K. ^{[22, 23]} ; Bonnivard, V. ^[12] ; Borgia, B. ^{[24, 14]} ; Borsini, S. ^[3] ; Boschini, M. J. ^[21] ; Bourquin, M. ^[8] ; Burger, J. ^[9] ; Cadoux, F. ^[8] ; Cai, X. D. ^[9] ; Capell, M. ^[9] ; Caroff, S. ^{[25, 26]} ; Casaus, J. ^[1] ; Castellini, G. ^[27] ; Cernuda, I. ^[1] ; Cerreta, D. ^{[2, 3]} ; Cervelli, F. ^[28] ; Chae, M. J. ^[29] ; Chang, Y. H. ^[30] ; Chen, A. I. ^[9] ; Chen, G. M. ^[31] ; Chen, H. ^[9] ; Chen, H. S. ^[31] ; Cheng, L. ^[32] ; Chou, H. Y. ^[30] ; Choumilov, E. ^[9] ; Choutko, V. ^[9] ; Chung, C. H. ^{[10, 11]} ; Clark, C. ^{[22, 23]} ; Clavero, R. ^{[33, 34]} ; Coignet, G. ^{[25, 26]} ; Consolandi, C. ^[9] ; Contin, A. ^{[9, 35, 36]} ; Corti, C. ^[19] ; Gil, E. Cortina ^[8] ; Coste, B. ^{[15, 13]} ; Creus, W. ^[30] ; Crispoltoni, M. ^{[2, 3]} ; Cui, Z. ^[32] ; Dai, Y. M. ^[37] ; Delgado, C. ^[1] ; Della Torre, S. ^[21] ; Demirkoz, M. B. ^[38] ; Derome, L. ^[12] ; Di Falco, S. ^[28] ; Di Masso, L. ^{[2, 3]} ; Dimiccoli, F. ^{[17, 15]} ; Diaz, C. ^[1] ; von Doetinchem, P. ^[19] ; Donnini, F. ^{[2, 3]} ; Duranti, M. ^{[2, 3]} ; D'Urso, D. ^{[3, 39]} ; Egorov, A. ^[9] ; Eline, A. ^[9] ; Eppling, F. J. ^[9] ; Eronen, T. ^[16] ; Fan, Y. Y. ^{[40, 41]} ; Farnesini, L. ^[3] ; Feng, J. ^{[42, 40, 25, 26]} ; Fiandrini, E. ^{[2, 3]} ; Fiasson, A. ^{[25, 26]} ; Finch, E. ^[43] ; Fisher, P. ^[9] ; Formato, V. ^{[3, 13]} ; Galaktionov, Y. ^[9] ; Gallucci, G. ^[28] ; Garcia, B. ^[1] ; Garcia-Lopez, R. ^{[33, 34]} ; Gargiulo, C. ^[13] ; Gast, H. ^{[10, 11]} ; Gebauer, I. ^[4] ; Gervasi, M. ^{[20, 21]} ; Ghelfi, A. ^[12] ; Giovacchini, F. ^[1] ; Goglov, P. ^[9] ; Gong, J. ^[44] ; Goy, C. ^{[25, 26]} ; Grabski, V. ^[45] ; Grandi, D. ^[21] ; Graziani, M. ^{[2, 3]} ; Guandalini, C. ^[36] ; Guerri, I. ^{[46, 28]} ; Guo, K. H. ^[42] ; Haas, D. ^[8] ; Habiby, M. ^[8] ; Haino, S. ^[40] ; Han, K. C. ^[47] ; He, Z. H. ^[42] ; Heil, M. ^[9] ; Hsieh, T. H. ^[9] ; Huang, Z. C. ^[42] ; Huh, C. ^[48] ; Incagli, M. ^[28] ; Ionica, M. ^[3] ; Jang, W. Y. ^[48] ; Jinchi, H. ^[47] ; Kanishev, K. ^{[17, 15, 13]} ; Kim, G. N. ^[48] ; Kim, K. S. ^[48] ; Kirn, Th. ^{[10, 11]} ; Korkmaz, M. A. ^[38] ; Kossakowski, R. ^{[25, 26]} ; Kounina, O. ^[9] ; Kounine, A. ^[9] ; Koutsenko, V. ^[9] ; Krafczyk, M. S. ^[9] ; La Vacca, G. ^[21] ; Laudi, E. ^{[2, 3]} ; Laurenti, G. ^[36] ; Lazzizzera, I. ^{[17, 15]} ; Lebedev, A. ^[9] ; Lee, H. T. ^[49] ; Lee, S. C. ^[40] ; Leluc, C. ^[8] ; Li, H. L. ^{[40, 50]} ; Li, J. Q. ^{[9, 44, 51]} ; Li, Q. ^{[9, 44, 51]} ; Li, T. X. ^[42] ; Li, W. ^[52] ; Li, Y. ^{[8, 42]} ; Li, Z. H. ^[31] ; Li, Z. Y. ^{[42, 40]} ; Lim, S. ^[48] ; Lin, C. H. ^[40] ; Lipari, P. ^[14] ; Lippert, T. ^{[6, 7]} ; Liu, D. ^[40] ; Liu, H. ^[44] ; Liu, Hu ^{[1, 53]} ; Lolli, M. ^[36] ; Lomtadze, T. ^[28] ; Lu, M. J. ^{[54, 15]} ; Lu, S. Q. ^{[42, 40]} ; Lu, Y. S. ^[31] ; Luebelsmeyer, K. ^{[10, 11]} ; Luo, F. ^[32] ; Luo, J. Z. ^[44] ; Lv, S. S. ^[42] ; Majka, R. ^[43] ; Mana, C. ^[1] ; Marin, J. ^[1] ; Martin, T. ^{[22, 23]} ; Martinez, G. ^[1] ; Masi, N. ; Maurin, D. ^[12] ; Menchaca-Rocha, A. ^[45] ; Meng, Q. ^[44] ; Mo, D. C. ^[42] ; Morescalchi, L. ^{[55, 28]} ; Mott, P. ^{[22, 23]} ; Mueller, M. ^{[10, 11]} ; Nelson, T. ^[19] ; Ni, J. Q. ^[42] ; Nikonov, N. ^[4] ; Nozzoli, F. ^{[3, 39]} ; Nunes, P. ^[5] ; Obermeier, A. ^{[10, 11]} ; Oliva, A. ^[1] ; Orcinha, M. ^[5] ; Palmonari, F. ; Palomares, C. ^[1] ; Paniccia, M. ^[8] ; Papi, A. ^[3] ; Pauluzzi, M. ^{[2, 3]} ; Pedreschi, E. ^[28] ; Pensotti, S. ^{[20, 21]} ; Pereira, R. ^[19] ; Picot-Clemente, N. ^[56] ; Pilo, F. ^[28] ; Piluso, A. ^{[2, 3]} ; Pizzolotto, C. ^{[3, 39]} ; Plyaskin, V. ^[9] ; Pohl, M. ^[8] ; Poireau, V. ^{[25, 26]} ; Putze, A. ^{[25, 26, 57]} ; Quadrani, L. ; Qi, X. M. ^[42] ; Qin, X. ^{[50, 3]} ; Qu, Z. Y. ^{[40, 58]} ; Raeihae, T. ^{[10, 11]} ; Rancoita, P. G. ^[21] ; Rapin, D. ^[8] ; Ricol, J. S. ^[12] ; Rodriguez, I. ^[1] ; Rosier-Lees, S. ^{[25, 26]} ; Rozhkov, A. ^[9] ; Rozza, D. ^[21] ; Sagdeev, R. ^[59] ; Sandweiss, J. ^[43] ; Saouter, P. ^[8] ; Schael, S. ^{[10, 11]} ; Schmidt, S. M. ^{[6, 7]} ; von Dratzig, A. Schulz ^{[10, 11]} ; Schwering, G. ^{[10, 11]} ; Scolieri, G. ^[3] ; Seo, E. S. ^[56] ; Shan, B. S. ^[52] ; Shan, Y. H. ^[52] ; Shi, J. Y. ^[44] ; Shi, X. Y. ^{[9, 60]} ; Shi, Y. M. ^[61] ; Siedenburg, T. ^{[10, 11]} ; Son, D. ^[48] ; Song, J. W. ^[32] ; Spada, F. ^[14] ; Spinella, F. ^[28] ; Sun, W. ^[9] ; Sun, W. H. ^{[9, 44]} ; Tacconi, M. ^{[21, 13]} ; Tang, C. P. ^[42] ; Tang, X. W. ^[31] ; Tang, Z. C. ^[31] ; Tao, L. ^{[25, 26]} ; Tescaro, D. ^{[33, 34]} ; Ting, Samuel C. C. ^[9] ; Ting, S. M. ^[9] ; Tomassetti, N. ^[12] ; Torsti, J. ^[16] ; Tuerkoglu, C. ^[38] ; Urban, T. ^{[22, 23]} ; Vagelli, V. ^{[4, 3]} ; Valente, E. ^{[24, 14]} ; Vannini, C. ^[28] ; Valtonen, E. ^[16] ; Vaurynovich, S. ^[9] ; Vecchi, M. ^[62] ; Velasco, M. ^[1] ; Vialle, J. P. ^{[25, 26]} ; Vitale, V. ^{[3, 39]} ; Vitillo, S. ^[8] ; Wang, L. Q. ^[32] ; Wang, N. H. ^[32] ; Wang, Q. L. ^[37] ; Wang, R. S. ^[61] ; Wang, X. ^[9] ; Wang, Z. X. ^[42] ; Weng, Z. L. ^[9] ; Whitman, K. ^[19] ; Wienkenhoever, J. ^{[10, 11]} ; Willenbrock, M. ^[9] ; Wu, H. ^[44] ; Wu, X. ^[8] ; Xia, X. ^{[1, 50]} ; Xie, M. ^{[9, 51]} ; Xie, S. ^[61] ; Xiong, R. Q. ^[44] ; Xu, N. S. ^[42] ; Xu, W. ^[9] ; Yan, Q. ^[9] ; Yang, J. ^[29] ; Yang, M. ^[31] ; Yang, Y. ^[63] ; Ye, Q. H. ^[61] ; Yi, H. ^[44] ; Yu, Y. J. ^[37] ; Yu, Z. Q. ^[31] ; Zeissler, S. ^[4] ; Zhang, C. ^[31] ; Zhang, J. H. ^[44] ; Zhang, M. T. ^[42] ; Zhang, S. D. ^{[9, 51]} ; Zhang, S. W. ^[31] ; Zhang, X. B. ^[42] ; Zhang, Z. ^[42] ; Zheng, Z. M. ^[52] ; Zhuang, H. L. ^[31] ; Zhukov, V. ^{[10, 11]} ; Zichichi, A. ^{[35, 36]} ; Zimmermann, N. ^{[10, 11]} ; Zuccon, P. ^[9] ; Collaboration, AMS Total Authors: 298
Affiliation: Show less -	^[1] CIEMAT, E-28040 Madrid - Spain ^[2] Univ Perugia, I-06100 Perugia - Italy ^[3] INFN Sez Perugia, I-06100 Perugia - Italy ^[4] Karlsruhe Inst Technol, Inst Expt Kernphys, D-76128 Karlsruhe - Germany ^[5] LIP, Lab Instrumentacao Fis Expt Particulas, P-1000 Lisbon - Portugal ^[6] Res Ctr Julich, JARA FAME, D-52425 Julich - Germany ^[7] Julich Supercomp Ctr, D-52425 Julich - Germany ^[8] Univ Geneva, DPNC, CH-1211 Geneva 4 - Switzerland ^[9] MIT, Cambridge, MA 02139 - USA ^[10] Rhein Westfal TH Aachen, JARA FAME, D-52056 Aachen - Germany ^[11] Rhein Westfal TH Aachen, Inst Phys, D-52056 Aachen - Germany ^[12] Univ Grenoble Alpes, CNRS, IN2P3, LPSC, F-38026 Grenoble - France ^[13] European Org Nucl Res CERN, CH-1211 Geneva 23 - Switzerland ^[14] INFN Sez Roma, I-100185 Rome - Italy ^[15] INFN TIFPA, I-38123 Trento - Italy ^[16] Univ Turku, Dept Phys & Astron, Space Res Lab, FI-20014 Turku - Finland ^[17] Univ Trent, I-38123 Trento - Italy ^[18] ASI, I-00133 Rome - Italy ^[19] Univ Hawaii, Dept Phys & Astron, Honolulu, HI 96822 - USA ^[20] Univ Milano Bicocca, I-20126 Milan - Italy ^[21] INFN Sez Milano Bicocca, I-20126 Milan - Italy ^[22] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 - USA ^[23] Jacobs Sverdrup, Houston, TX 77058 - USA ^[24] Univ Roma La Sapienza, I-00185 Rome - Italy ^[25] CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux - France ^[26] Univ Savoie Mont Blanc, F-74941 Annecy Le Vieux - France ^[27] CNR IROE, I-50125 Florence - Italy ^[28] INFN Sez Pisa, I-56100 Pisa - Italy ^[29] Ewha Womans Univ, Dept Phys, Seoul 120750 - South Korea ^[30] Natl Cent Univ, Chungli 32054, Tao Yuan - Taiwan ^[31] Chinese Acad Sci, Inst High Energy Phys, Beijing 100039 - Peoples R China ^[32] Shandong Univ SDU, Jinan 250100, Shandong - Peoples R China ^[33] Inst Astrofis Canarias, E-38205 San Cristobal la Laguna - Spain ^[34] Univ La Laguna, Dept Astrofis, E-38206 San Cristobal la Laguna, Tenerife - Spain ^[35] Univ Bologna, I-40126 Bologna - Italy ^[36] INFN Sez Bologna, I-40126 Bologna - Italy ^[37] Chinese Acad Sci, Inst Elect Engn, Beijing 100190 - Peoples R China ^[38] METU, Dept Phys, TR-06800 Ankara - Turkey ^[39] ASDC, I-00133 Rome - Italy ^[40] Acad Sinica, Inst Phys, Taipei 11529 - Taiwan ^[41] Xi An Jiao Tong Univ, Xian 710049 - Peoples R China ^[42] Sun Yat Sen Univ, Guangzhou 510275, Guangdong - Peoples R China ^[43] Yale Univ, Dept Phys, New Haven, CT 06520 - USA ^[44] Southeast Univ, Nanjing 210096, Jiangsu - Peoples R China ^[45] Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF - Mexico ^[46] Univ Pisa, I-56100 Pisa - Italy ^[47] NCSIST, Taoyuan 325 - Taiwan ^[48] Kyungpook Natl Univ, CHEP, Taegu 702701 - South Korea ^[49] ASGC, Taipei 11529 - Taiwan ^[50] Shandong Univ, Jinan 250100, Shandong - Peoples R China ^[51] Harbin Inst Technol, Harbin 150001 - Peoples R China ^[52] Beihang Univ BUAA, Beijing 100191 - Peoples R China ^[53] Huazhong Univ Sci & Technol, Wuhan 430074 - Peoples R China ^[54] Univ Sci & Technol China, Anhua 230026 - Peoples R China ^[55] Univ Siena, I-53100 Siena - Italy ^[56] Univ Maryland, IPST, College Pk, MD 20742 - USA ^[57] CNRS, Lab Annecy Le Vieux Phys Particules, LAPTh, F-74941 Annecy Le Vieux - France ^[58] Nankai Univ, Tianjin 300071 - Peoples R China ^[59] Univ Maryland, East West Ctr Space Sci, College Pk, MD 20742 - USA ^[60] Beijing Normal Univ, Beijing 100875 - Peoples R China ^[61] Shanghai Jiao Tong Univ, Shanghai 200030 - Peoples R China ^[62] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil ^[63] Natl Cheng Kung Univ, Tainan 701 - Taiwan Total Affiliations: 63
Document type:	Journal article
Source:	Physical Review Letters; v. 115, n. 21 NOV 17 2015.
Web of Science Citations:	154
Abstract
Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law. (AU)

FAPESP's process:	14/19149-7 - Indirect dark matter search with the AMS-02 detector
Grantee:	Manuela Vecchi
Support Opportunities:	Research Grants - Young Investigators Grants


FAPESP's process:	14/50747-8 - Indirect dark matter search with AMS-02 data
Grantee:	Manuela Vecchi
Support Opportunities:	Regular Research Grants

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