Search for the X17 particle in $^{7}\mathrm{Li}(\mathrm{p},\mathrm{e}^+ \mathrm{e}^{-}) ^{8}\mathrm{Be}$ processes with the MEG II detector

Autor: The MEG II collaboration, Afanaciev, K., Baldini, A. M., Ban, S., Benmansour, H., Boca, G., Cattaneo, P. W., Cavoto, G., Cei, F., Chiappini, M., Corvaglia, A., Maso, G. Dal, De Bari, A., De Gerone, M., Barusso, L. Ferrari, Francesconi, M., Galli, L., Gallucci, G., Gatti, F., Gerritzen, L., Grancagnolo, F., Grandoni, E. G., Grassi, M., Grigoriev, D. N., Hildebrandt, M., Ignatov, F., Ikeda, F., Iwamoto, T., Karpov, S., Kettle, P. -R., Khomutov, N., Kolesnikov, A., Kravchuk, N., Krylov, V., Kuchinskiy, N., Leonetti, F., Li, W., Malyshev, V., Matsushita, A., Meucci, M., Mihara, S., Molzon, W., Mori, T., Nicolò, D., Nishiguchi, H., Ochi, A., Ootani, W., Oya, A., Palo, D., Panareo, M., Papa, A., Pettinacci, V., Popov, A., Renga, F., Ritt, S., Rossella, M., Scarpellini, A. Rozhdestvensky. S., Schwendimann, P., Signorelli, G., Takahashi, M., Uchiyama, Y., Venturini, A., Vitali, B., Voena, C., Yamamoto, K., Yokota, R., Yonemoto, T.

The observation of a resonance structure in the opening angle of the electron-positron pairs in the $^{7}$Li(p,\ee) $^{8}$Be reaction was claimed and interpreted as the production and subsequent decay of a hypothetical particle (X17). Similar excesse

Externí odkaz: http://arxiv.org/abs/2411.07994

A search for $\mu^+\to e^+\gamma$ with the first dataset of the MEG II experiment

Autor: MEG II collaboration, Afanaciev, K., Baldini, A. M., Ban, S., Baranov, V., Benmansour, H., Biasotti, M., Boca, G., Cattaneo, P. W., Cavoto, G., Cei, F., Chiappini, M., Chiarello, G., Corvaglia, A., Cuna, F., Maso, G. Dal, De Bari, A., De Gerone, M., Barusso, L. Ferrari, Francesconi, M., Galli, L., Gallucci, G., Gatti, F., Gerritzen, L., Grancagnolo, F., Grandoni, E. G., Grassi, M., Grigoriev, D. N., Hildebrandt, M., Ieki, K., Ignatov, F., Ikeda, F., Iwamoto, T., Karpov, S., Kettle, P. -R., Khomutov, N., Kobayashi, S., Kolesnikov, A., Kravchuk, N., Krylov, V., Kuchinskiy, N., Kyle, W., Libeiro, T., Malyshev, V., Matsushita, A., Meucci, M., Mihara, S., Molzon, W., Mori, Toshinori, Nakao, M., Nicolò, D., Nishiguchi, H., Ochi, A., Ogawa, S., Onda, R., Ootani, W., Oya, A., Palo, D., Panareo, M., Papa, A., Pettinacci, V., Popov, A., Renga, F., Ritt, S., Rossella, M., Rozhdestvensky, A., Schwendimann, P., Shimada, K., Signorelli, G., Takahashi, M., Tassielli, G. F., Toyoda, K., Uchiyama, Y., Usami, M., Venturini, A., Vitali, B., Voena, C., Yamamoto, K., Yanai, K., Yonemoto, T., Yoshida, K., Yudin, Yu. V.

The MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports the result of a search for the decay $\mu^+\to e^+\gamma$ from data taken in the first physics run in 2021. No excess of events over the expected background is observe

Externí odkaz: http://arxiv.org/abs/2310.12614

Search for lepton flavour violating muon decay mediated by a new light particle in the MEG experiment

Autor: Baldini, A. M., Berg, F., Biasotti, M., Boca, G., Cattaneo, P. W., Cavoto, G., Cei, F., Chiappini, M., Chiarello, G., Chiri, C., Corvaglia, A., de Bari, A., De Gerone, M., Francesconi, M., Galli, L., Gatti, F., Grancagnolo, F., Grassi, M., Grigoriev, D. N., Hildebrandt, M., Hodge, Z., Ieki, K., Ignatov, F., Iwai, R., Iwamoto, T., Kobayashi, S., Kettle, P. -R., Kyle, W., Khomutov, N., Kolesnikov, A., Kravchuk, N., Kuchinskiy, N., Libeiro, T., Lim, G. M. A., Malyshev, V., Matsuzawa, N., Meucci, M., Mihara, S., Molzon, W., Mori, Toshinori, Mtchedilishvili, A., Nakao, M., Natori, H., Nicolò, D., Nishiguchi, H., Nishimura, M., Ogawa, S., Onda, R., Ootani, W., Oya, A., Palo, D., Panareo, M., Papa, A., Pettinacci, V., Pizzigoni, G., Popov, A., Renga, F., Ritt, S., Rozhdestvensky, A., Rossella, M., Sawada, R., Schwendimann, P., Signorelli, G., Stoykov, A., Tassielli, G. F., Toyoda, K., Uchiyama, Y., Usami, M., Voena, C., Yanai, K., Yudin, Yu. V.

We present the first direct search for lepton flavour violating muon decay mediated by a new light particle X, $\mu^+ \to \mathrm{e}^+\mathrm{X}, \mathrm{X} \to \gamma\gamma$. This search uses a dataset resulting from $7.5\times 10^{14}$ stopped muon

Externí odkaz: http://arxiv.org/abs/2005.00339

COMET Phase-I Technical Design Report

Autor: The COMET Collaboration, Abramishvili, R., Adamov, G., Akhmetshin, R. R., Allin, A., Angélique, J. C., Anishchik, V., Aoki, M., Aznabayev, D., Bagaturia, I., Ban, G., Ban, Y., Bauer, D., Baygarashev, D., Bondar, A. E., Cârloganu, C., Carniol, B., Chau, T. T., Chen, J. K., Chen, S. J., Cheung, Y. E., da Silva, W., Dauncey, P. D., Densham, C., Devidze, G., Dornan, P., Drutskoy, A., Duginov, V., Eguchi, Y., Epshteyn, L. B., Evtoukhovich, P., Fayer, S., Fedotovich, G. V., Finger Jr, M., Finger, M., Fujii, Y., Fukao, Y., Gabriel, J. L., Gay, P., Gillies, E., Grigoriev, D. N., Gritsay, K., Hai, V. H., Hamada, E., Hashim, I. H., Hashimoto, S., Hayashi, O., Hayashi, T., Hiasa, T., Ibrahim, Z. A., Igarashi, Y., Ignatov, F. V., Iio, M., Ishibashi, K., Issadykov, A., Itahashi, T., Jansen, A., Jiang, X. S., Jonsson, P., Kachelhoffer, T., Kalinnikov, V., Kaneva, E., Kapusta, F., Katayama, H., Kawagoe, K., Kawashima, R., Kazak, N., Kazanin, V. F., Kemularia, O., Khvedelidze, A., Koike, M., Kormoll, T., Kozlov, G. A., Kozyrev, A. N., Kravchenko, M., Krikler, B., Kumsiashvili, G., Kuno, Y., Kuriyama, Y., Kurochkin, Y., Kurup, A., Lagrange, B., Lai, J., Lee, M. J., Li, H. B., Litchfield, R. P., Li, W. G., Loan, T., Lomidze, D., Lomidze, I., Loveridge, P., Macharashvili, G., Makida, Y., Mao, Y. J., Markin, O., Matsuda, Y., Melkadze, A., Melnik, A., Mibe, T., Mihara, S., Miyamoto, N., Miyazaki, Y., Idris, F. Mohamad, Azmi, K. A. Mohamed Kamal, Moiseenko, A., Moritsu, M., Mori, Y., Motoishi, T., Nakai, H., Nakai, Y., Nakamoto, T., Nakamura, Y., Nakatsugawa, Y., Nakazawa, Y., Nash, J., Natori, H., Niess, V., Nioradze, M., Nishiguchi, H., Noguchi, K., Numao, T., O'Dell, J., Ogitsu, T., Ohta, S., Oishi, K., Okamoto, K., Okamura, T., Okinaka, K., Omori, C., Ota, T., Pasternak, J., Paulau, A., Picters, D., Ponariadov, V., Quémener, G., Ruban, A. A., Rusinov, V., Sabirov, B., Sakamoto, H., Sarin, P., Sasaki, K., Sato, A., Sato, J., Semertzidis, Y. K., Shigyo, N., Shoukavy, Dz., Slunecka, M., Stöckinger, D., Sugano, M., Tachimoto, T., Takayanagi, T., Tanaka, M., Tang, J., Tao, C. V., Teixeira, A. M., Tevzadze, Y., Thanh, T., Tojo, J., Tolmachev, S. S., Tomasek, M., Tomizawa, M., Toriashvili, T., Trang, H., Trekov, I., Tsamalaidze, Z., Tsverava, N., Uchida, T., Uchida, Y., Ueno, K., Velicheva, E., Volkov, A., Vrba, V., Abdullah, W. A. T. Wan, Warin-Charpentier, P., Wong, M. L., Wong, T. S., Wu, C., Xing, T. Y., Yamaguchi, H., Yamamoto, A., Yamanaka, M., Yamane, T., Yang, Y., Yano, T., Yao, W. C., Yeo, B., Yoshida, H., Yoshida, M., Yoshioka, T., Yuan, Y., Yudin, Yu. V., Zdorovets, M. V., Zhang, J., Zhang, Y., Zuber, K.

Publikováno v: Progress of Theoretical and Experimental Physics, Volume 2020, Issue 3, March 2020, 033C01

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 aluminium nucleus ($\mu-e$ conversion,

Externí odkaz: http://arxiv.org/abs/1812.09018

Vacuum-Compatible, Ultra-Thin-Wall Straw Tracker; Detector construction, Thinner straw R&D, and the brand-new graphite-straw development

Autor: Nishiguchi, H., Danielsson, H., Hamada, E., Hashimoto, Y., Kamei, N., Mihara, S., Osawa, O., Suzuki, J., Tsamalaidze, Z., Tsverava, N., Ueno, K., Volkov, A., Watanabe, K.

Publikováno v: In Nuclear Inst. and Methods in Physics Research, A 1 November 2022 1042