COMET Phase-I technical design report
The COMET Collaboration
R. Abramishvili10, G. Adamov10,16, R. R. Akhmetshin3,29, A. Allin22, J. C. Angélique4, V. Anishchik1, M. Aoki30, D. Aznabayev14, I. Bagaturia10, G. Ban4, Y. Ban31, D. Bauer11, D. Baygarashev14, A. E. Bondar3,29, C. Cârloganu8, B. Carniol4, T. T. Chau30, J. K. Chen35, S. J. Chen27, Y. E. Cheung27, W. da Silva34, P. D. Dauncey11, C. Densham32, G. Devidze36, P. Dornan11,∗, A. Drutskoy22,25, V. Duginov16, Y. Eguchi30, L. B. Epshteyn3,29,28, P. Evtoukhovitch16,2, S. Fayer11, G. V. Fedotovich3,29, M. Finger Jr6, M. Finger6, Y. Fujii26, Y. Fukao18, J. L. Gabriel4, P. Gay8, E. Gillies11, D. N. Grigoriev3,29,28, K. Gritsay16, V. H. Hai40, E. Hamada18, I. H. Hashim24, S. Hashimoto20, O. Hayashi30, T. Hayashi30, T. Hiasa30, Z. A. Ibrahim24, Y. Igarashi18, F. V. Ignatov3,29, M. Iio18, K. Ishibashi20, A. Issadykov14, T. Itahashi30, A. Jansen38, X. S. Jiang13, P. Jonsson11, T. Kachelhoffer5, V. Kalinnikov16, E. Kaneva16, F. Kapusta34, H. Katayama30, K. Kawagoe20, R. Kawashima20, N. Kazak2, V. F. Kazanin3,29, O. Kemularia10, A. Khvedelidze16,10, M. Koike39, T. Kormoll38, G. A. Kozlov16, A. N. Kozyrev3,29, M. Kravchenko16,1, B. Krikler11, G. Kumsiashvili30, Y. Kuno30, Y. Kuriyama19, Y. Kurochkin2, A. Kurup11, B. Lagrange11,19, J. Lai30, M. J. Lee12,∗, H. B. Li13,7, R. P. Litchfield11, W. G. Li13, T. Loan40, D. Lomidze10, I. Lomidze10, P. Loveridge32, G. Macharashvili36, Y. Makida18, Y. J. Mao31, O. Markin22,25, Y. Matsuda30, A. Melkadze10, A. Melnik2, T. Mibe18, S. Mihara18, N. Miyamoto30, Y. Miyazaki20, F. Mohamad Idris24, K. A. Mohamed Kamal Azmi24, A. Moiseenko16, M. Moritsu18, Y. Mori19, T. Motoishi30, H. Nakai30, Y. Nakai20, T. Nakamoto18, Y. Nakamura30, Y. Nakatsugawa13, Y. Nakazawa30, J. Nash26, H. Natori12,41, V. Niess8, M. Nioradze36, H. Nishiguchi18, K. Noguchi20, T. Numao37, J. O’Dell32, T. Ogitsu18, S. Ohta30, K. Oishi20, K. Okamoto30, T. Okamura18, K. Okinaka30, C. Omori18, T. Ota23, J. Pasternak11, A. Paulau2,16, D. Picters30, V. Ponariadov1, G. Quémener4, A. A. Ruban3,29, V. Rusinov22,25, B. Sabirov16, H. Sakamoto30, P. Sarin15, K. Sasaki18, A. Sato30, J. Sato33, Y. K. Semertzidis12,17, N. Shigyo20, Dz. Shoukavy2, M. Slunecka6, D. Stöckinger38, M. Sugano18, T. Tachimoto30, T. Takayanagi30, M. Tanaka18, J. Tang35, C. V. Tao40, A. M. Teixeira8, Y. Tevzadze†,36, T. Thanh40, J. Tojo20, S. S. Tolmachev3,29, M. Tomasek9, M. Tomizawa18, T. Toriashvili10, H. Trang40, I. Trekov36, Z. Tsamalaidze16,10, N. Tsverava16,10, T. Uchida18, Y. Uchida11,∗, K. Ueno18, E. Velicheva16, A. Volkov16, V. Vrba9, W. A. T. Wan Abdullah24, P. Warin-Charpentier34, M. L. Wong30, T. S. Wong30, C. Wu13,27,30, T. Y. Xing13,7, H. Yamaguchi18, A. Yamamoto18, M. Yamanaka21,42, T. Yamane30, Y. Yang20, T. Yano30, W. C. Yao30, B. Yeo17, H. Yoshida30, M. Yoshida18, T. Yoshioka20, Y. Yuan13, Yu. V. Yudin3,29, M. V. Zdorovets14, J. Zhang13, Y. Zhang13, and K. Zuber38
1Belarusian State University (BSU), 220030, Minsk, Belarus
2B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 220072, Minsk, Belarus
3Budker Institute of Nuclear Physics (BINP), Novosibirsk, 630090, Russia
4Laboratoire de Physique Corpusculaire (LPC), 14000 Caen, France
5Computing Center of the National Institute of Nuclear Physics and Particle Physics (CC-IN2P3), 69627 Villeurbanne, France
6Charles University, Prague, 116 36, Czech Republic
7University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
8Laboratoire de Physique de Clermont (LPC), CNRS-IN2P3 and Université Clermont Auvergne, 63178 Clermont-Ferrand, France
9Czech Technical University, Prague, 160 00, Czech Republic
10Georgian Technical University (GTU), 0160 Tbilisi, Georgia
11Imperial College London, London SW7 2BW, UK
12Institute for Basic Science, Daejeon, 34051, Korea
13Institute of High Energy Physics (IHEP), Beijing 100049, People’s Republic of China
14Institute of Nuclear Physics (INP), Almaty, 050032, Kazakhstan
15Indian Institute of Technology Bombay, Mumbai 400076, India
16Joint Institute for Nuclear Research (JINR), Dubna, 141980, Russia
17Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
18High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0031, Japan
19Research Reactor Institute, Kyoto University, Kyoto 606-8501, Japan
20Kyushu University, Fukuoka 819-0395, Japan
21Kyushu Sangyo University, Fukuoka 813-8503, Japan
22P. N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, 119991, Russia
23Departamento de Fídesica Teórica and Instituto de Fídesica Teórica, IFT-UAM/CSIC, Universidad Autónomade Madrid, 28049 Madrid, Spain
24National Centre for Particle Physics, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
25Moscow Physical Engineering Institute, National University, Moscow, 115409, Russia
26Monash University, Melbourne, Victoria 3800, Australia
27Nanjing University, Nanjing 210093, People’s Republic of China
28Novosibirsk State Technical University (NSTU), Novosibirsk, 630073, Russia
29Novosibirsk State University (NSU), Novosibirsk, 630090, Russia
30Osaka University, Osaka 560-0043, Japan
31Peking University, Beijing 100871, People’s Republic of China
32STFC Rutherford Appleton Laboratory (RAL), Didcot, Oxon OX11 0QX, UK
33Saitama University, Saitama 338-8570, Japan
34Laboratory of Nuclear and High Energy Physics (LPNHE), CNRS-IN2P3 and Sorbonne Université, 75252 Paris, France
35Sun Yat-Sen University, Guangzhou 510275, People’s Republic of China
36High Energy Physics Institute of I. Javakhishvili Tbilisi State University (HEPI-TSU), 0186 Tbilisi, Georgia
37TRIUMF, Vancouver, BC V6T 2A3, Canada
38Technische Universität Dresden, 01062 Dresden, Germany
39Utsunomiya University, Utsunomiya, Tochigi 321-8585, Japan
40University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
41Present address: Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
42Present address: Nambu Yoichiro Institute of Theoretical and Experimental Physics (NITEP), Osaka City University, Osaka 558-8585, Japan
The Technical Design for the COMET Phase-I experiment is presented in this paper. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into electrons in the field of an aluminum nucleus (μ–e conversion, μ−N → e−N ); a lepton flavor-violating process. The experimental sensitivity goal for this process in the Phase-I experiment is 3.1 × 10−15, or 90% upper limit of a branching ratio of 7 × 10−15, which is a factor of 100 improvement over the existing limit. The expected number of background events is 0.032. To achieve the target sensitivity and background level, the 3.2 kW 8 GeV proton beam from J-PARC will be used. Two types of detectors, CyDet and StrECAL, will be used for detecting the μ–e conversion events, and for measuring the beam-related background events in view of the Phase-II experiment, respectively. Results from simulation on signal and background estimations are also described.