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1. Determination of the CKM angle ϕ 3 from a combination of Belle and Belle II results

Author

The Belle and Belle II collaborations, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, S. Al Said, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, K. Belous, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, L. Bierwirth, T. Bilka, S. Bilokin, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, R. Cheaib, P. Cheema, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-K. Choi, Y. Choi, S. Choudhury, L. Corona, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dreyer, S. Dubey, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, T. Grammatico, S. Granderath, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, T. Hara, H. Hayashii, S. Hazra, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, K. Inami, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, H. Junkerkalefeld, D. Kalita, A. B. Kaliyar, J. Kandra, T. Kawasaki, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, J. Kumar, M. Kumar, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, M. J. Lee, D. Levit, P. M. Lewis, C. Li, L. K. Li, Y. Li, Y. B. Li, J. Libby, M. H. Liu, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, L. Martel, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, C. Miller, M. Mirra, K. Miyabayashi, H. Miyake, G. B. Mohanty, N. Molina-Gonzalez, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, K. R. Nakamura, M. Nakao, Y. Nakazawa, A. Narimani Charan, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, M. Neu, C. Niebuhr, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, P. Oskin, F. Otani, P. Pakhlov, G. Pakhlova, A. Panta, S. Pardi, K. Parham, H. Park, S.-H. Park, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schmitt, G. Schnell, C. Schwanda, M. Schwickardi, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, M. Sumihama, K. Sumisawa, W. Sutcliffe, N. Suwonjandee, M. Takizawa, U. Tamponi, K. Tanida, F. Tenchini, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, Y. Uematsu, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, X. L. Wang, Z. Wang, A. Warburton, S. Watanuki, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. Yelton, J. H. Yin, K. Yoshihara, C. Z. Yuan, B. Zhang, Y. Zhang, V. Zhilich, Q. D. Zhou, and V. I. Zhukova

Subjects
B Physics, CKM Angle Gamma, CP Violation, e +-e − Experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We report a determination of the CKM angle ϕ 3, also known as γ, from a combination of measurements using samples of up to 711 fb −1 from the Belle experiment and up to 362 fb −1 from the Belle II experiment. We combine results from analyses of B + → DK +, B + → Dπ +, and B + → D * K + decays, where D is an admixture of D 0 and D ¯ 0 $$ {\overline{D}}^0 $$ mesons, in a likelihood fit to obtain ϕ 3 = (75.2 ± 7.6) ° . We also briefly discuss the interpretation of this result.

Published
2024
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2. Measurement of the energy dependence of the e + e − → B B ¯ $$ B\overline{B} $$ , B B ¯ ∗ $$ B{\overline{B}}^{\ast } $$ , and B ∗ B ¯ ∗ $$ {B}^{\ast }{\overline{B}}^{\ast } $$ cross sections at Belle II

Author

The Belle II collaboration, I. Adachi, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, M. Bauer, A. Baur, A. Beaubien, F. Becherer, J. Becker, P. K. Behera, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, J. Cochran, L. Corona, J. X. Cui, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dorner, K. Dort, D. Dossett, S. Dreyer, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, A. Garmash, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, T. Grammatico, S. Granderath, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, K. Hara, T. Hara, C. Harris, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, A. Hershenhorn, T. Higuchi, E. C. Hill, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, S. Ito, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, A. Johnson, K. K. Joo, H. Junkerkalefeld, H. Kakuno, M. Kaleta, D. Kalita, A. B. Kaliyar, J. Kandra, K. H. Kang, S. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Ketter, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, Y. Kulii, T. Kuhr, J. Kumar, M. Kumar, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, R. Leboucher, F. R. Le Diberder, M. J. Lee, P. Leitl, P. Leo, D. Levit, P. M. Lewis, C. Li, L. K. Li, S. X. Li, Y. Li, Y. B. Li, J. Libby, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, A. Lozar, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, L. Martel, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, T. Matsuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, M. Mirra, S. Mitra, K. Miyabayashi, H. Miyake, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, M. Nakao, Y. Nakazawa, A. Narimani Charan, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, M. Neu, C. Niebuhr, N. K. Nisar, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, Y. Onuki, P. Oskin, F. Otani, P. Pakhlov, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, S. Pardi, K. Parham, H. Park, J. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, I. Peruzzi, R. Peschke, R. Pestotnik, F. Pham, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, S. Privalov, H. Purwar, N. Rad, P. Rados, G. Raeuber, S. Raiz, N. Rauls, K. Ravindran, M. Reif, S. Reiter, M. Remnev, L. Reuter, I. Ripp-Baudot, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. Sahoo, D. A. Sanders, S. Sandilya, A. Sangal, L. Santelj, Y. Sato, V. Savinov, B. Scavino, S. Schneider, M. Schnepf, C. Schwanda, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, C. P. Shen, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, K. Smith, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, Z. S. Stottler, R. Stroili, J. Strube, Y. Sue, M. Sumihama, K. Sumisawa, W. Sutcliffe, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, S. Tanaka, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, N. Toutounji, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, Y. Uematsu, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, G. S. Varner, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, X. L. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. Yelton, J. H. Yin, K. Yoshihara, C. Z. Yuan, L. Zani, F. Zeng, B. Zhang, Y. Zhang, V. Zhilich, J. S. Zhou, Q. D. Zhou, X. Y. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
e +-e − Experiments, Quarkonium, Spectroscopy, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We report measurements of the e + e − → B B ¯ $$ B\overline{B} $$ , B B ¯ ∗ $$ B{\overline{B}}^{\ast } $$ , and B ∗ B ¯ ∗ $$ {B}^{\ast }{\overline{B}}^{\ast } $$ cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected by the Belle II experiment. We reconstruct one B meson in a large number of hadronic final states and use its momentum to identify the production process. In the first 2 – 5 MeV above B ∗ B ¯ ∗ $$ {B}^{\ast }{\overline{B}}^{\ast } $$ threshold, the e + e − → B ∗ B ¯ ∗ $$ {B}^{\ast }{\overline{B}}^{\ast } $$ cross section increases rapidly. This may indicate the presence of a pole close to the threshold.

Published
2024
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3. Measurements of the branching fractions of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$ , Ξ c 0 → Ξ 0 η $$ {\Xi}_c^0\to {\Xi}^0\eta $$ , and Ξ c 0 → Ξ 0 η ′ $$ {\Xi}_c^0\to {\Xi}^0{\eta}^{\prime } $$ and asymmetry parameter of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$

Author

The Belle and Belle II collaboration, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, C. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, L. Corona, J. X. Cui, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, T. Fillinger, C. Finck, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, K. Gudkova, I. Haide, S. Halder, Y. Han, T. Hara, C. Harris, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, K. Inami, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, E.-J. Jang, S. Jia, Y. Jin, A. Johnson, K. K. Joo, H. Junkerkalefeld, M. Kaleta, J. Kandra, K. H. Kang, S. Kang, G. Karyan, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, P. Križan, P. Krokovny, T. Kuhr, Y. Kulii, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, K. Lalwani, T. Lam, J. S. Lange, M. Laurenza, R. Leboucher, M. J. Lee, C. Lemettais, P. Leo, D. Levit, P. M. Lewis, L. K. Li, S. X. Li, Y. Li, Y. B. Li, J. Libby, Z. Liptak, M. H. Liu, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, C. Martellini, A. Martens, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, C. Miller, M. Mirra, S. Mitra, K. Miyabayashi, G. B. Mohanty, S. Moneta, H.-G. Moser, M. Mrvar, I. Nakamura, M. Nakao, Y. Nakazawa, M. Naruki, Z. Natkaniec, A. Natochii, M. Nayak, G. Nazaryan, M. Neu, M. Niiyama, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, G. Pakhlova, S. Pardi, K. Parham, H. Park, J. Park, S.-H. Park, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, M. Remnev, L. Reuter, I. Ripp-Baudot, G. Rizzo, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, S. Schneider, M. Schnepf, C. Schwanda, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, C. P. Shen, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, E. Solovieva, W. Song, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, M. Sumihama, K. Sumisawa, N. Suwonjandee, H. Svidras, M. Takahashi, M. Takizawa, S. Tanaka, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, A. Vossen, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, Z. Wang, A. Warburton, S. Watanuki, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. Yelton, J. H. Yin, Y. M. Yook, K. Yoshihara, C. Z. Yuan, L. Zani, F. Zeng, B. Zhang, V. Zhilich, J. S. Zhou, Q. D. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
Branching fraction, Charm Physics, e +-e − Experiments, Particle and Resonance Production, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present a study of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$ , Ξ c 0 → Ξ 0 η $$ {\Xi}_c^0\to {\Xi}^0\eta $$ , and Ξ c 0 → Ξ 0 η ′ $$ {\Xi}_c^0\to {\Xi}^0{\eta}^{\prime } $$ decays using the Belle and Belle II data samples, which have integrated luminosities of 980 fb −1 and 426 fb −1, respectively. We measure the following relative branching fractions B Ξ c 0 → Ξ 0 π 0 / B Ξ c 0 → Ξ − π + = 0.48 ± 0.02 stat ± 0.03 syst , B Ξ c 0 → Ξ 0 η / B Ξ c 0 → Ξ − π + = 0.11 ± 0.01 stat ± 0.01 syst , B Ξ c 0 → Ξ 0 η ′ / B Ξ c 0 → Ξ − π + = 0.08 ± 0.02 stat ± 0.01 syst $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\pi}^0\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.48\pm 0.02\left(\textrm{stat}\right)\pm 0.03\left(\textrm{syst}\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0\eta \right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.11\pm 0.01\left(\textrm{stat}\right)\pm 0.01\left(\textrm{syst}\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\eta}^{\prime}\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.08\pm 0.02\left(\textrm{stat}\right)\pm 0.01\left(\textrm{syst}\right)\end{array}} $$ for the first time, where the uncertainties are statistical (stat) and systematic (syst). By multiplying by the branching fraction of the normalization mode, B Ξ c 0 → Ξ − π + $$ \mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right) $$ , we obtain the following absolute branching fraction results B Ξ c 0 → Ξ 0 π 0 = 6.9 ± 0.3 stat ± 0.5 syst ± 1.3 norm × 10 − 3 , B Ξ c 0 → Ξ 0 η = 1.6 ± 0.2 stat ± 0.2 syst ± 0.3 norm × 10 − 3 , B Ξ c 0 → Ξ 0 η ′ = 1.2 ± 0.3 stat ± 0.1 syst ± 0.2 norm × 10 − 3 , $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\pi}^0\right)=\left(6.9\pm 0.3\left(\textrm{stat}\right)\pm 0.5\left(\textrm{syst}\right)\pm 1.3\left(\operatorname{norm}\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0\eta \right)=\left(1.6\pm 0.2\left(\textrm{stat}\right)\pm 0.2\left(\textrm{syst}\right)\pm 0.3\left(\operatorname{norm}\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\varXi}_c^0\to {\Xi}^0{\eta}^{\prime}\right)=\left(1.2\pm 0.3\left(\textrm{stat}\right)\pm 0.1\left(\textrm{syst}\right)\pm 0.2\left(\operatorname{norm}\right)\right)\times {10}^{-3},\end{array}} $$ where the third uncertainties are from B Ξ c 0 → Ξ − π + $$ \mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right) $$ . The asymmetry parameter for Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$ is measured to be α Ξ c 0 → Ξ 0 π 0 = − 0.90 ± 0.15 stat ± 0.23 syst $$ \alpha \left({\Xi}_c^0\to {\Xi}^0{\pi}^0\right)=-0.90\pm 0.15\left(\textrm{stat}\right)\pm 0.23\left(\textrm{syst}\right) $$ .

Published
2024
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4. Search for lepton-flavor-violating τ − → μ − μ + μ − decays at Belle II

Author

The Belle II collaboration, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, R. Cheaib, P. Cheema, C. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, J. Cochran, L. Corona, J. X. Cui, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dorner, K. Dort, D. Dossett, S. Dreyer, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, T. Grammatico, S. Granderath, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, T. Hara, C. Harris, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, D. E. Jaffe, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, H. Junkerkalefeld, M. Kaleta, D. Kalita, A. B. Kaliyar, J. Kandra, K. H. Kang, S. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, Y. Kulii, J. Kumar, M. Kumar, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, K. Lalwani, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, K. Lautenbach, R. Leboucher, F. R. Le Diberder, M. J. Lee, P. Leo, C. Lemettais, D. Levit, P. M. Lewis, L. K. Li, S. X. Li, Y. Li, Y. B. Li, J. Libby, M. H. Liu, Q. Y. Liu, Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, C. Miller, M. Mirra, S. Mitra, K. Miyabayashi, G. B. Mohanty, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, K. R. Nakamura, M. Nakao, Y. Nakazawa, A. Narimani Charan, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, M. Neu, C. Niebuhr, J. Ninkovic, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, F. Otani, P. Pakhlov, G. Pakhlova, S. Pardi, K. Parham, H. Park, J. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, I. Prudiev, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, L. Reuter, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, S. Schneider, C. Schwanda, M. Schwickardi, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, C. P. Shen, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, K. Smith, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, Y. Sue, M. Sumihama, K. Sumisawa, W. Sutcliffe, N. Suwonjandee, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, S. Tanaka, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Tsaklidis, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, A. Vossen, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, X. L. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, C. Wessel, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. Yelton, J. H. Yin, Y. M. Yook, K. Yoshihara, C. Z. Yuan, L. Zani, F. Zeng, B. Zhang, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
e +-e − Experiments, Flavour Physics, Tau Physics, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present the result of a search for the charged-lepton-flavor violating decay τ − → μ − μ + μ − using a 424 fb −1 sample of data recorded by the Belle II experiment at the SuperKEKB e + e − collider. The selection of e + e − → τ + τ − events is based on an inclusive reconstruction of the non-signal tau decay, and on a boosted decision tree to suppress background. We observe one signal candidate, which is compatible with the expectation from background processes. We set a 90% confidence level upper limit of 1.9 × 10 −8 on the branching fraction of the τ − → μ − μ + μ − decay, which is the most stringent bound to date.

Published
2024
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5. Test of light-lepton universality in τ decays with the Belle II experiment

Author

The Belle II collaboration, I. Adachi, K. Adamczyk, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, F. Bianchi, L. Bierwirth, T. Bilka, S. Bilokin, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, R. Cheaib, P. Cheema, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, L. Corona, J. X. Cui, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dorner, K. Dort, D. Dossett, S. Dreyer, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, T. Grammatico, S. Granderath, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, Y. Han, T. Hara, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, D. E. Jaffe, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, H. Junkerkalefeld, M. Kaleta, D. Kalita, A. B. Kaliyar, J. Kandra, S. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, Y. Kulii, J. Kumar, M. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, K. Lalwani, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, K. Lautenbach, R. Leboucher, F. R. Le Diberder, M. J. Lee, P. Leo, C. Lemettais, D. Levit, P. M. Lewis, C. Li, L. K. Li, S. X. Li, Y. Li, Y. B. Li, J. Libby, Z. Liptak, M. H. Liu, Q. Y. Liu, Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, C. Miller, M. Mirra, S. Mitra, K. Miyabayashi, H. Miyake, R. Mizuk, G. B. Mohanty, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, K. R. Nakamura, M. Nakao, H. Nakazawa, Y. Nakazawa, A. Narimani Charan, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, M. Neu, C. Niebuhr, J. Ninkovic, S. Nishida, A. Novosel, S. Ogawa, Y. Onishchuk, H. Ono, F. Otani, P. Pakhlov, G. Pakhlova, A. Panta, S. Pardi, K. Parham, H. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, I. Prudiiev, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schmitt, C. Schwanda, M. Schwickardi, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, X. D. Shi, T. Shillington, J.-G. Shiu, D. Shtol, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, Y. Sue, M. Sumihama, K. Sumisawa, W. Sutcliffe, N. Suwonjandee, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, S. Tanaka, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, X. L. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. Yelton, J. H. Yin, K. Yoshihara, C. Z. Yuan, Y. Yusa, L. Zani, F. Zeng, B. Zhang, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
e +-e − Experiments, Tau Physics, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present a measurement of the ratio R μ = B τ − → μ − ν ¯ μ ν τ / B τ − → e − ν ¯ e ν τ $$ {R}_{\mu }=\mathcal{B}\left({\tau}^{-}\to {\mu}^{-}{\overline{\nu}}_{\mu }{\nu}_{\tau}\right)/\mathcal{B}\left({\tau}^{-}\to {e}^{-}{\overline{\nu}}_e{\nu}_{\tau}\right) $$ of branching fractions B $$ \mathcal{B} $$ of the τ lepton decaying to muons or electrons using data collected with the Belle II detector at the SuperKEKB e + e − collider. The sample has an integrated luminosity of 362 ± 2 fb −1 at a centre-of-mass energy of 10.58 GeV. Using an optimised event selection, a binned maximum likelihood fit is performed using the momentum spectra of the electron and muon candidates. The result, R μ = 0.9675 ± 0.0007 ± 0.0036, where the first uncertainty is statistical and the second is systematic, is the most precise to date. It provides a stringent test of the light-lepton universality, translating to a ratio of the couplings of the muon and electron to the W boson in τ decays of 0.9974 ± 0.0019, in agreement with the standard model expectation of unity.

Published
2024
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6. Measurement of the branching fractions of B ¯ $$ \overline{B} $$ → D (*) K − K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ and B ¯ $$ \overline{B} $$ → D (*) D s − $$ {D}_s^{-} $$ decays at Belle II

Author

The Belle II collaboration, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, L. Corona, J. X. Cui, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dorner, K. Dort, D. Dossett, S. Dreyer, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, M. Garcia-Hernandez, R. Garg, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, K. Gudkova, I. Haide, S. Halder, Y. Han, T. Hara, C. Harris, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, K. Inami, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, D. E. Jaffe, E.-J. Jang, S. Jia, Y. Jin, A. Johnson, K. K. Joo, H. Junkerkalefeld, A. B. Kaliyar, J. Kandra, K. H. Kang, S. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, P. Križan, P. Krokovny, T. Kuhr, Y. Kulii, J. Kumar, M. Kumar, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, K. Lalwani, T. Lam, J. S. Lange, M. Laurenza, K. Lautenbach, R. Leboucher, F. R. Le Diberder, M. J. Lee, C. Lemettais, P. Leo, D. Levit, P. M. Lewis, L. K. Li, S. X. Li, Y. Li, Y. B. Li, J. Libby, Z. Liptak, M. H. Liu, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, C. Martellini, A. Martens, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, F. Meier, M. Merola, C. Miller, M. Mirra, S. Mitra, K. Miyabayashi, R. Mizuk, G. B. Mohanty, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, M. Nakao, Y. Nakazawa, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, M. Neu, M. Niiyama, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, G. Pakhlova, S. Pardi, K. Parham, H. Park, J. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, M. Remnev, L. Reuter, I. Ripp-Baudot, G. Rizzo, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schmitt, S. Schneider, M. Schnepf, C. Schwanda, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, C. P. Shen, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, M. Sumihama, H. Svidras, M. Takizawa, U. Tamponi, S. Tanaka, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, A. Vossen, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, C. Wessel, J. Wiechczynski, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, S. B. Yang, J. Yelton, J. H. Yin, Y. M. Yook, K. Yoshihara, C. Z. Yuan, L. Zani, F. Zeng, B. Zhang, V. Zhilich, J. S. Zhou, Q. D. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
B Physics, Branching fraction, e +-e − Experiments, Particle and Resonance Production, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present measurements of the branching fractions of eight B ¯ 0 $$ {\overline{B}}^0 $$ → D (*)+ K − K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ , B − → D (*)0 K − K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ decay channels. The results are based on data from SuperKEKB electron-positron collisions at the Υ(4S) resonance collected with the Belle II detector, corresponding to an integrated luminosity of 362 fb −1. The event yields are extracted from fits to the distributions of the difference between expected and observed B meson energy, and are efficiency-corrected as a function of m(K − K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ ) and m(D (*) K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ ) in order to avoid dependence on the decay model. These results include the first observation of B ¯ 0 $$ {\overline{B}}^0 $$ → D + K − K S 0 $$ {K}_S^0 $$ , B − → D* 0 K − K S 0 $$ {K}_S^0 $$ , and B ¯ 0 $$ {\overline{B}}^0 $$ → D* + K − K S 0 $$ {K}_S^0 $$ decays and a significant improvement in the precision of the other channels compared to previous measurements. The helicity-angle distributions and the invariant mass distributions of the K − K S ∗ 0 $$ {K}_{(S)}^{\left(\ast \right)0} $$ systems are compatible with quasi-two-body decays via a resonant transition with spin-parity J P = 1− for the K − K S 0 $$ {K}_S^0 $$ systems and J P = 1+ for the K − K* 0 systems. We also present measurements of the branching fractions of four B ¯ 0 $$ {\overline{B}}^0 $$ → D (*)+ D s − $$ {D}_s^{-} $$ , B − → D (*)0 D s − $$ {D}_s^{-} $$ decay channels with a precision compatible to the current world averages.

Published
2024
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7. Study of Υ(10753) decays to π + π − Υ(nS) final states at Belle II

Author

The Belle II collaboration, I. Adachi, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, L. Corona, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, T. V. Dong, M. Dorigo, K. Dort, S. Dreyer, S. Dubey, G. Dujany, P. Ecker, M. Eliachevitch, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, T. Grammatico, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, T. Hara, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, T. Higuchi, M. Hoek, M. Hohmann, P. Horak, C.-L. Hsu, T. Humair, T. Iijima, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, K. K. Joo, H. Junkerkalefeld, H. Kakuno, D. Kalita, A. B. Kaliyar, J. Kandra, K. H. Kang, S. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, M. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, R. Leboucher, F. R. Le Diberder, M. J. Lee, D. Levit, C. Li, L. K. Li, Y. Li, Y. B. Li, J. Libby, M. Liu, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, L. Martel, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, C. Miller, M. Mirra, K. Miyabayashi, H. Miyake, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, Y. Nakazawa, A. Narimani Charan, M. Naruki, D. Narwal, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, C. Niebuhr, S. Nishida, S. Ogawa, Y. Onishchuk, H. Ono, Y. Onuki, P. Oskin, F. Otani, P. Pakhlov, G. Pakhlova, A. Panta, S. Pardi, K. Parham, H. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, P. Rados, G. Raeuber, S. Raiz, N. Rauls, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schwanda, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. P. Shen, X. D. Shi, T. Shillington, T. Shimasaki, J.-G. Shiu, D. Shtol, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, R. Stroili, M. Sumihama, K. Sumisawa, W. Sutcliffe, H. Svidras, M. Takizawa, U. Tamponi, K. Tanida, F. Tenchini, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, M. Veronesi, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, X. L. Wang, Z. Wang, A. Warburton, S. Watanuki, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, S. B. Yang, J. Yelton, J. H. Yin, K. Yoshihara, C. Z. Yuan, Y. Yusa, L. Zani, B. Zhang, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, and V. I. Zhukova

Subjects
e +-e − Experiments, Exotics, Quarkonium, Spectroscopy, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present an analysis of the process e + e − → π + π − Υ(nS) (where n = 1, 2, or 3) reconstructed in 19.6 fb −1 of Belle II data during a special run of the SuperKEKB collider at four energy points near the peak of the Υ(10753) resonance. By analyzing the mass distribution of the π + π − Υ(nS) system and the Born cross sections of the e + e − → π + π − Υ(nS) process, we report the first observation of Υ(10753) decays to the π + π − Υ(1S) and π + π − Υ(2S) final states, and find no evidence for decays to π + π − Υ(3S). Possible intermediate states in the π + π − Υ(1S, 2S) transitions are also investigated, and no evidence for decays proceeding via the π ∓ Z b ± $$ {\pi}^{\mp }{Z}_b^{\pm } $$ or f 0(980)Υ(nS) intermediate states is found. We measure Born cross sections for the e + e − → π + π − Υ(nS) process that, combined with results from Belle, obtain the mass and width of Υ(10753) to be (10756.6 ± 2.7 ± 0.9) MeV/c 2 and (29.0 ± 8.8 ± 1.2) MeV, respectively. The relative ratios of the Born cross sections at the Υ(10753) resonance peak are also reported for the first time.

Published
2024
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8. Measurement of branching-fraction ratios and CP asymmetries in B ± → D CP± K ± decays at Belle and Belle II

Author

The Belle and Belle II collaboration, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, M. Barrett, J. Baudot, M. Bauer, A. Baur, A. Beaubien, F. Becherer, J. Becker, P. K. Behera, K. Belous, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, V. Chekelian, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-K. Choi, Y. Choi, S. Choudhury, J. Cochran, L. Corona, L. M. Cremaldi, T. Czank, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dreyer, S. Dubey, G. Dujany, P. Ecker, M. Eliachevitch, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, A. Garmash, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, S. Granderath, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, T. Hara, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, M. T. Hedges, A. Heidelbach, I. Heredia de la Cruz, M. Hernández Villanueva, A. Hershenhorn, T. Higuchi, E. C. Hill, M. Hoek, M. Hohmann, P. Horak, W.-S. Hou, C.-L. Hsu, T. Iijima, K. Inami, N. Ipsita, A. Ishikawa, S. Ito, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, A. Johnson, H. Junkerkalefeld, H. Kakuno, A. B. Kaliyar, J. Kandra, K. H. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Ketter, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, M. Kumar, R. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, R. Leboucher, F. R. Le Diberder, M. J. Lee, P. Leitl, D. Levit, P. M. Lewis, C. Li, J. Li, L. K. Li, Y. Li, J. Libby, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, T. Luo, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, S. Marcello, C. Marinas, L. Martel, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, T. Matsuda, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, M. Mirra, K. Miyabayashi, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, T. Nakano, Y. Nakazawa, A. Narimani Charan, M. Naruki, Z. Natkaniec, A. Natochii, L. Nayak, G. Nazaryan, N. K. Nisar, S. Nishida, S. Ogawa, H. Ono, Y. Onuki, P. Oskin, F. Otani, P. Pakhlov, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, S. Pardi, K. Parham, H. Park, S.-H. Park, B. Paschen, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, I. Peruzzi, R. Peschke, R. Pestotnik, F. Pham, M. Piccolo, L. E. Piilonen, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, N. Rad, P. Rados, G. Raeuber, S. Raiz, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, L. B. Rizzuto, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. Sahoo, S. Sandilya, A. Sangal, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schmitt, G. Schnell, C. Schwanda, A. J. Schwartz, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, X. D. Shi, T. Shillington, J.-G. Shiu, D. Shtol, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, Z. S. Stottler, R. Stroili, J. Strube, M. Sumihama, K. Sumisawa, W. Sutcliffe, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, N. Toutounji, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, S. Uehara, Y. Uematsu, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, G. S. Varner, K. E. Varvell, A. Vinokurova, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, D. Wang, E. Wang, M.-Z. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, M. Welsch, C. Wessel, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. H. Yin, K. Yoshihara, C. Z. Yuan, L. Zani, Y. Zhang, V. Zhilich, J. S. Zhou, Q. D. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
B Physics, CKM Angle Gamma, CP Violation, e +-e − Experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We report results from a study of B ± → DK ± decays followed by D decaying to the CP-even final state K + K − and CP-odd final state K S 0 π 0 $$ {K}_S^0{\pi}^0 $$ , where D is an admixture of D 0 and D ¯ 0 $$ {\overline{D}}^0 $$ states. These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity-triangle angle ϕ 3. The results are based on a combined analysis of the final data set of 772 × 106 B B ¯ $$ B\overline{B} $$ pairs collected by the Belle experiment and a data set of 198 × 106 B B ¯ $$ B\overline{B} $$ pairs collected by the Belle II experiment, both in electron-positron collisions at the Υ(4S) resonance. We measure the CP asymmetries to be A $$ \mathcal{A} $$ CP+ = (+12.5 ± 5.8 ± 1.4)% and A $$ \mathcal{A} $$ CP− = (−16.7 ± 5.7 ± 0.6)%, and the ratios of branching fractions to be R $$ \mathcal{R} $$ CP+ = 1.164 ± 0.081 ± 0.036 and R $$ \mathcal{R} $$ CP− = 1.151 ± 0.074 ± 0.019. The first contribution to the uncertainties is statistical, and the second is systematic. The asymmetries A $$ \mathcal{A} $$ CP+ and A $$ \mathcal{A} $$ CP− have similar magnitudes and opposite signs; their difference corresponds to 3.5 standard deviations. From these values we calculate 68.3% confidence intervals of (8.5 ° < ϕ 3 < 16.5 ° ) or (84.5 ° < ϕ 3 < 95.5 ° ) or (163.3 ° < ϕ 3 < 171.5 ° ) and 0.321 < r B < 0.465.

Published
2024
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9. Measurement of CP asymmetries and branching-fraction ratios for B ± → DK ± and Dπ ± with D → K S 0 $$ {K}_{\textrm{S}}^0 $$ K ± π ∓ using Belle and Belle II data

Author

The Belle and Belle II collaborations, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, M. Barrett, J. Baudot, M. Bauer, A. Baur, A. Beaubien, J. Becker, P. K. Behera, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, R. Cheaib, P. Cheema, V. Chekelian, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-K. Choi, Y. Choi, S. Choudhury, J. Cochran, L. Corona, L. M. Cremaldi, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, S. Dreyer, S. Dubey, G. Dujany, P. Ecker, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, R. Garg, A. Garmash, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan, G. Giakoustidis, R. Giordano, A. Giri, B. Gobbo, R. Godang, O. Gogota, P. Goldenzweig, W. Gradl, E. Graziani, D. Greenwald, Z. Gruberová, T. Gu, Y. Guan, K. Gudkova, S. Halder, Y. Han, T. Hara, K. Hayasaka, S. Hazra, M. T. Hedges, I. Heredia de la Cruz, M. Hernández Villanueva, A. Hershenhorn, T. Higuchi, E. C. Hill, M. Hoek, M. Hohmann, W.-S. Hou, C.-L. Hsu, T. Iijima, K. Inami, N. Ipsita, A. Ishikawa, S. Ito, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, D. E. Jaffe, E.-J. Jang, Q. P. Ji, S. Jia, Y. Jin, A. Johnson, H. Junkerkalefeld, A. B. Kaliyar, J. Kandra, K. H. Kang, G. Karyan, T. Kawasaki, F. Keil, C. Ketter, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, M. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, K. Lautenbach, R. Leboucher, F. R. Le Diberder, P. Leitl, D. Levit, P. M. Lewis, C. Li, L. K. Li, J. Libby, Q. Y. Liu, Z. Q. Liu, D. Liventsev, S. Longo, T. Lueck, T. Luo, C. Lyu, Y. Ma, M. Maggiora, S. P. Maharana, R. Maiti, S. Maity, G. Mancinelli, R. Manfredi, E. Manoni, M. Mantovano, D. Marcantonio, C. Marinas, C. Martellini, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, T. Matsuda, K. Matsuoka, D. Matvienko, S. K. Maurya, J. A. McKenna, R. Mehta, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, M. Mirra, K. Miyabayashi, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, S. Mondal, S. Moneta, H.-G. Moser, M. Mrvar, R. Mussa, I. Nakamura, Y. Nakazawa, A. Narimani Charan, M. Naruki, Z. Natkaniec, A. Natochii, L. Nayak, G. Nazaryan, N. K. Nisar, S. Nishida, S. Ogawa, H. Ono, Y. Onuki, P. Oskin, F. Otani, P. Pakhlov, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, S. Pardi, K. Parham, H. Park, S.-H. Park, A. Passeri, S. Patra, S. Paul, T. K. Pedlar, I. Peruzzi, R. Peschke, R. Pestotnik, F. Pham, M. Piccolo, L. E. Piilonen, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, N. Rad, P. Rados, G. Raeuber, S. Raiz, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, M. Roehrken, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. Sahoo, S. Sandilya, A. Sangal, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schmitt, G. Schnell, M. Schnepf, C. Schwanda, A. J. Schwartz, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, W. Shan, C. Sharma, X. D. Shi, T. Shillington, J.-G. Shiu, D. Shtol, A. Sibidanov, F. Simon, J. B. Singh, J. Skorupa, R. J. Sobie, M. Sobotzik, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, P. Stavroulakis, S. Stefkova, Z. S. Stottler, R. Stroili, M. Sumihama, K. Sumisawa, W. Sutcliffe, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, K. Tanida, F. Tenchini, A. Thaller, O. Tittel, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, I. Tsaklidis, M. Uchida, I. Ueda, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, G. S. Varner, K. E. Varvell, M. Veronesi, V. S. Vismaya, L. Vitale, V. Vobbilisetti, R. Volpe, B. Wach, M. Wakai, S. Wallner, E. Wang, M.-Z. Wang, Z. Wang, A. Warburton, M. Watanabe, S. Watanuki, M. Welsch, C. Wessel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, J. H. Yin, K. Yoshihara, C. Z. Yuan, Y. Yusa, L. Zani, Y. Zhang, V. Zhilich, J. S. Zhou, Q. D. Zhou, V. I. Zhukova, and R. Žlebčík

Subjects
B Physics, CKM Angle Gamma, CP Violation, e +-e − Experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We measure CP asymmetries and branching-fraction ratios for B ± → DK ± and Dπ ± decays with D → K S 0 $$ {K}_{\textrm{S}}^0 $$ K ± π ∓, where D is a superposition of D 0 and D ¯ $$ \overline{D} $$ 0. We use the full data set of the Belle experiment, containing 772 × 106 B B ¯ $$ B\overline{B} $$ pairs, and data from the Belle II experiment, containing 387 × 106 B B ¯ $$ B\overline{B} $$ pairs, both collected in electron-positron collisions at the Υ(4S) resonance. Our results provide model-independent information on the unitarity triangle angle ϕ 3.

Published
2023
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10. Erratum to: Combined analysis of Belle and Belle II data to determine the CKM angle ϕ 3 using B+ → D( K S 0 $$ {\textrm{K}}_{\textrm{S}}^0 $$ h+h − )h+ decays

Author

The BELLE and Belle II collaborations, F. Abudinén, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, S. Al Said, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, R. Ayad, V. Babu, S. Bacher, S. Baehr, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, J. Baudot, J. Becker, P. K. Behera, K. Belous, J. V. Bennett, F. U. Bernlochner, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, F. Bianchi, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, G. Bonvicini, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, D. Červenkov, P. Cheema, V. Chekelian, A. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, S.-J. Cho, S.-K. Choi, Y. Choi, S. Choudhury, D. Cinabro, L. Corona, S. Cunliffe, T. Czank, S. Das, F. Dattola, E. De La Cruz-Burelo, G. de Marino, S. K. Maurya, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dossett, S. Dubey, G. Dujany, M. Eliachevitch, D. Epifanov, P. Feichtinger, D. Ferlewicz, T. Fillinger, S. Fiore, A. Fodor, F. Forti, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, V. Gaur, A. Gaz, R. Giordano, A. Giri, A. Glazov, R. Godang, P. Goldenzweig, B. Golob, W. Gradl, E. Graziani, D. Greenwald, T. Gu, Y. Guan, K. Gudkova, J. Guilliams, C. Hadjivasiliou, S. Halder, T. Hara, O. Hartbrich, K. Hayasaka, H. Hayashii, S. Hazra, I. Heredia de la Cruz, A. Hershenhorn, T. Higuchi, E. C. Hill, W.-S. Hou, C.-L. Hsu, T. Iijima, K. Inami, A. Ishikawa, M. Iwasaki, W. W. Jacobs, E.-J. Jang, Y. Jin, H. Junkerkalefeld, A. B. Kaliyar, K. H. Kang, R. Karl, G. Karyan, Y. Kato, C. Ketter, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, S. Korpar, E. Kovalenko, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, J. Kumar, M. Kumar, R. Kumar, K. Kumara, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, C. La Licata, L. Lanceri, J. S. Lange, R. Leboucher, S. C. Lee, P. Leitl, J. Li, S. X. Li, L. Li Gioi, J. Libby, K. Lieret, Z. Liptak, Q. Y. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, M. Maggiora, R. Maiti, S. Maity, R. Manfredi, E. Manoni, S. Marcello, A. Martini, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, J. A. McKenna, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, K. Miyabayashi, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, H.-G. Moser, F. Mueller, C. Murphy, R. Mussa, K. R. Nakamura, T. Nakano, M. Nakao, M. Naruki, D. Narwal, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, N. K. Nisar, S. Nishida, K. Nishimura, Y. Onishchuk, H. Ono, P. Oskin, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, K. Parham, S.-H. Park, A. Passeri, A. Pathak, S. Patra, R. Pestotnik, L. E. Piilonen, T. Podobnik, S. Pokharel, L. Polat, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, A. Rabusov, P. Rados, S. Raiz, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, L. B. Rizzuto, S. H. Robertson, M. Röhrken, J. M. Roney, A. Rostomyan, N. Rout, D. Sahoo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, G. Schnell, J. Schueler, A. J. Schwartz, Y. Seino, A. Selce, K. Senyo, M. E. Sevior, M. Shapkin, C. Sharma, T. Shillington, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, A. Soffer, E. Solovieva, S. Spataro, B. Spruck, S. Stefkova, Z. S. Stottler, R. Stroili, K. Sumisawa, W. Sutcliffe, S. Y. Suzuki, M. Tabata, M. Takizawa, K. Tanida, F. Tenchini, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, M. Uchida, I. Ueda, T. Uglov, K. Uno, S. Uno, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, A. Vinokurova, L. Vitale, H. M. Wakeling, E. Wang, M.-Z. Wang, X. L. Wang, A. Warburton, S. Watanuki, O. Werbycka, C. Wessel, E. Won, B. D. Yabsley, W. Yan, H. Ye, K. Yoshihara, Y. Yusa, L. Zani, Y. Zhai, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, and V. I. Zhukova

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Published
2022
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11. B-flavor tagging at Belle II

Author

F. Abudinén, N. Akopov, A. Aloisio, V. Babu, Sw. Banerjee, M. Bauer, J. V. Bennett, F. U. Bernlochner, M. Bessner, S. Bettarini, T. Bilka, S. Bilokin, D. Biswas, D. Bodrov, J. Borah, M. Bračko, P. Branchini, A. Budano, M. Campajola, G. Casarosa, C. Cecchi, R. Cheaib, V. Chekelian, C. Chen, Y. Q. Chen, H. -E. Cho, S. Cunliffe, G. De Nardo, G. De Pietro, R. de Sangro, S. Dey, A. Di Canto, F. Di Capua, T. V. Dong, G. Dujany, P. Ecker, M. Eliachevitch, T. Ferber, F. Forti, E. Ganiev, A. Gaz, M. Gelb, J. Gemmler, R. Godang, P. Goldenzweig, E. Graziani, K. Hara, A. Hershenhorn, T. Higuchi, E. C. Hill, M. Hohmann, T. Humair, G. Inguglia, H. Junkerkalefeld, R. Karl, Y. Kato, T. Keck, C. Kiesling, C. -H. Kim, S. Kohani, I. Komarov, T. M. G. Kraetzschmar, P. Križan, J. F. Krohn, T. Kuhr, J. Kumar, K. Kumara, S. Kurz, S. Lacaprara, C. La Licata, M. Laurenza, K. Lautenbach, S. C. Lee, K. Lieret, L. Li Gioi, Q. Y. Liu, S. Longo, M. Maggiora, E. Manoni, C. Marinas, A. Martini, F. Meier, M. Merola, F. Metzner, M. Milesi, K. Miyabayashi, G. B. Mohanty, F. Mueller, C. Murphy, E. R. Oxford, S. -H. Park, A. Passeri, F. Pham, L. E. Piilonen, S. Pokharel, M. T. Prim, C. Pulvermacher, P. Rados, M. Ritter, A. Rostomyan, S. Sandilya, L. Santelj, Y. Sato, A. J. Schwartz, M. E. Sevior, A. Soffer, S. Spataro, R. Stroili, W. Sutcliffe, D. Tagnani, M. Takizawa, U. Tamponi, F. Tenchini, E. Torassa, P. Urquijo, L. Vitale, Y. Yusa, L. Zani, Q. D. Zhou, R. Žlebčík, and A. Zupanc

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom ( ) mesons at Belle II. The algorithms provide essential inputs for measurements of quark-flavor mixing and charge-parity violation. We validate and evaluate the performance of the algorithms using hadronic decays with flavor-specific final states reconstructed in a data set corresponding to an integrated luminosity of 62.8 fb $$^{-1}$$ - 1 , collected at the resonance with the Belle II detector at the SuperKEKB collider. We measure the total effective tagging efficiency to be $$\begin{aligned} \varepsilon _\mathrm{eff} = \big (30.0 \pm 1.2(\text {stat}) \pm 0.4(\text {syst})\big )\% \end{aligned}$$ ε eff = ( 30.0 ± 1.2 ( stat ) ± 0.4 ( syst ) ) % for a category-based algorithm and $$\begin{aligned} \varepsilon _\mathrm{eff} = \big (28.8 \pm 1.2(\text {stat}) \pm 0.4(\text {syst})\big )\% \end{aligned}$$ ε eff = ( 28.8 ± 1.2 ( stat ) ± 0.4 ( syst ) ) % for a deep-learning-based algorithm.

Published
2022
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12. Combined analysis of Belle and Belle II data to determine the CKM angle ϕ 3 using B + → D( K S 0 $$ {K}_S^0 $$ h + h − )h + decays

Author

The Belle and Belle II collaborations, F. Abudinén, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, S. Al Said, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, R. Ayad, V. Babu, S. Bacher, S. Baehr, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, J. Baudot, J. Becker, P. K. Behera, K. Belous, J. V. Bennett, F. U. Bernlochner, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, F. Bianchi, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, G. Bonvicini, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, D. Červenkov, P. Cheema, V. Chekelian, A. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, S.-J. Cho, S.-K. Choi, Y. Choi, S. Choudhury, D. Cinabro, L. Corona, S. Cunliffe, T. Czank, S. Das, F. Dattola, E. De La Cruz-Burelo, G. de Marino, S. K. Maurya, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, D. Dossett, S. Dubey, G. Dujany, M. Eliachevitch, D. Epifanov, P. Feichtinger, D. Ferlewicz, T. Fillinger, S. Fiore, A. Fodor, F. Forti, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, V. Gaur, A. Gaz, R. Giordano, A. Giri, A. Glazov, R. Godang, P. Goldenzweig, B. Golob, W. Gradl, E. Graziani, D. Greenwald, T. Gu, Y. Guan, K. Gudkova, J. Guilliams, C. Hadjivasiliou, S. Halder, T. Hara, O. Hartbrich, K. Hayasaka, H. Hayashii, S. Hazra, I. Heredia de la Cruz, A. Hershenhorn, T. Higuchi, E. C. Hill, W.-S. Hou, C.-L. Hsu, T. Iijima, K. Inami, A. Ishikawa, M. Iwasaki, W. W. Jacobs, E.-J. Jang, Y. Jin, H. Junkerkalefeld, A. B. Kaliyar, K. H. Kang, R. Karl, G. Karyan, Y. Kato, C. Ketter, C. Kiesling, C.-H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, S. Korpar, E. Kovalenko, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, J. Kumar, M. Kumar, R. Kumar, K. Kumara, A. Kuzmin, Y.-J. Kwon, S. Lacaprara, Y.-T. Lai, C. La Licata, L. Lanceri, J. S. Lange, R. Leboucher, S. C. Lee, P. Leitl, J. Li, S. X. Li, L. Li Gioi, J. Libby, K. Lieret, Z. Liptak, Q. Y. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, M. Maggiora, R. Maiti, S. Maity, R. Manfredi, E. Manoni, S. Marcello, A. Martini, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, J. A. McKenna, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, K. Miyabayashi, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, H.-G. Moser, F. Mueller, C. Murphy, R. Mussa, K. R. Nakamura, T. Nakano, M. Nakao, M. Naruki, D. Narwal, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, N. K. Nisar, S. Nishida, K. Nishimura, Y. Onishchuk, H. Ono, P. Oskin, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, K. Parham, S.-H. Park, A. Passeri, A. Pathak, S. Patra, R. Pestotnik, L. E. Piilonen, T. Podobnik, S. Pokharel, L. Polat, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, A. Rabusov, P. Rados, S. Raiz, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, L. B. Rizzuto, S. H. Robertson, M. Röhrken, J. M. Roney, A. Rostomyan, N. Rout, D. Sahoo, D. A. Sanders, S. Sandilya, L. Santelj, Y. Sato, V. Savinov, B. Scavino, G. Schnell, J. Schueler, A. J. Schwartz, Y. Seino, A. Selce, K. Senyo, M. E. Sevior, M. Shapkin, C. Sharma, T. Shillington, B. Shwartz, A. Sibidanov, F. Simon, J. B. Singh, A. Soffer, E. Solovieva, S. Spataro, B. Spruck, S. Stefkova, Z. S. Stottler, R. Stroili, K. Sumisawa, W. Sutcliffe, S. Y. Suzuki, M. Tabata, M. Takizawa, K. Tanida, F. Tenchini, R. Tiwary, D. Tonelli, E. Torassa, K. Trabelsi, M. Uchida, I. Ueda, T. Uglov, K. Uno, S. Uno, Y. Ushiroda, S. E. Vahsen, R. van Tonder, K. E. Varvell, A. Vinokurova, L. Vitale, H. M. Wakeling, E. Wang, M.-Z. Wang, X. L. Wang, A. Warburton, S. Watanuki, O. Werbycka, C. Wessel, E. Won, B. D. Yabsley, W. Yan, H. Ye, K. Yoshihara, Y. Yusa, L. Zani, Y. Zhai, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, and V. I. Zhukova

Subjects
B Physics, CKM Angle Gamma, e +-e − Experiments, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract We present a measurement of the Cabibbo-Kobayashi-Maskawa unitarity triangle angle ϕ 3 (also known as γ) using a model-independent Dalitz plot analysis of B + → D ( K S 0 $$ {K}_S^0 $$ h + h − )h +, where D is either a D 0 or D ¯ $$ \overline{D} $$ 0 meson and h is either a π or K. This is the first measurement that simultaneously uses Belle and Belle II data, combining samples corresponding to integrated luminosities of 711 fb −1 and 128 fb −1, respectively. All data were accumulated from energy-asymmetric e + e − collisions at a centre-of-mass energy corresponding to the mass of the Υ(4S) resonance. We measure ϕ 3 = (78.4 ± 11.4 ± 0.5 ± 1.0)°, where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is from the uncertainties on external measurements of the D-decay strong-phase parameters.

Published
2022
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13. Measurement of inclusive forward neutron production cross section in proton-proton collisions at s = 13 $$ \sqrt{s}=13 $$ TeV with the LHCf Arm2 detector

Author

The LHCf collaboration, O. Adriani, E. Berti, L. Bonechi, M. Bongi, R. D’Alessandro, S. Detti, M. Haguenauer, Y. Itow, K. Kasahara, Y. Makino, K. Masuda, H. Menjo, Y. Muraki, K. Ohashi, P. Papini, S. Ricciarini, T. Sako, N. Sakurai, K. Sato, M. Shinoda, T. Suzuki, T. Tamura, A. Tiberio, S. Torii, A. Tricomi, W. C. Turner, M. Ueno, and Q. D. Zhou

Subjects
Forward physics, Hadron-Hadron scattering (experiments), Unfolding, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract In this paper, we report the measurement relative to the production of forward neutrons in proton-proton collisions at s = 13 $$ \sqrt{s}=13 $$ TeV obtained using the LHCf Arm2 detector at the Large Hadron Collider. The results for the inclusive differential production cross section are presented as a function of energy in three different pseudorapidity regions: η > 10.76, 8.99 < η < 9.22 and 8.81 < η < 8.99. The analysis was performed using a data set acquired in June 2015 that corresponds to an integrated luminosity of 0.194 nb−1. The measurements were compared with the predictions of several hadronic interaction models used to simulate air showers generated by Ultra High Energy Cosmic Rays. None of these generators showed good agreement with the data for all pseudorapidity intervals. For η > 10.76, no model is able to reproduce the observed peak structure at around 5 TeV and all models underestimate the total production cross section: among them, QGSJET II-04 shows the smallest deficit with respect to data for the whole energy range. For 8.99 < η < 9.22 and 8.81 < η < 8.99, the models having the best overall agreement with data are SIBYLL 2.3 and EPOS-LHC, respectively: in particular, in both regions SIBYLL 2.3 is able to reproduce the observed peak structure at around 1.5–2.5 TeV.

Published
2018
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14. {Measurement of the \ensuremath{\Lambda}c+ Lifetime}

Author

F. Abudinén, L. Aggarwal, H. Ahmed, J. K. Ahn, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, V. Babu, H. Bae, P. Bambade, Sw. Banerjee, S. Bansal, J. Baudot, M. Bauer, A. Baur, A. Beaubien, J. Becker, J. V. Bennett, E. Bernieri, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, V. Bhardwaj, F. Bianchi, T. Bilka, D. Biswas, D. Bodrov, A. Bolz, G. Bonvicini, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, M. -C. Chang, P. Chang, R. Cheaib, P. Cheema, C. Chen, Y. Q. Chen, Y. -T. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H. -E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, S. Choudhury, D. Cinabro, L. Corona, L. M. Cremaldi, S. Cunliffe, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dreyer, G. Dujany, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, G. Finocchiaro, K. Flood, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli, E. Ganiev, M. Garcia-Hernandez, A. Gaz, A. Gellrich, G. Ghevondyan, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, P. Goldenzweig, W. Gradl, S. Granderath, D. Greenwald, T. Gu, Y. Guan, K. Gudkova, J. Guilliams, S. Halder, K. Hara, O. Hartbrich, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, I. Heredia de la Cruz, M. Hernández Villanueva, A. Hershenhorn, T. Higuchi, M. Hohmann, T. Humair, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, S. Ito, R. Itoh, M. Iwasaki, Y. Iwasaki, P. Jackson, W. W. Jacobs, D. E. Jaffe, Q. P. Ji, Y. Jin, H. Junkerkalefeld, M. Kaleta, J. Kandra, K. H. Kang, R. Karl, G. Karyan, C. Kiesling, C. -H. Kim, D. Y. Kim, K. -H. Kim, Y. -K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, T. Kuhr, J. Kumar, R. Kumar, K. Kumara, T. Kunigo, Y. -J. Kwon, S. Lacaprara, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, R. Leboucher, S. C. Lee, P. Leitl, D. Levit, L. K. Li, S. X. Li, Y. B. Li, J. Libby, Z. Liptak, Q. Y. Liu, D. Liventsev, S. Longo, T. Lueck, C. Lyu, M. Maggiora, R. Maiti, S. Maity, R. Manfredi, E. Manoni, S. Marcello, C. Marinas, L. Martel, A. Martini, L. Massaccesi, M. Masuda, K. Matsuoka, D. Matvienko, J. A. McKenna, F. Meier, M. Merola, M. Milesi, C. Miller, K. Miyabayashi, G. B. Mohanty, N. Molina-Gonzalez, S. Moneta, H. Moon, H. -G. Moser, M. Mrvar, R. Mussa, I. Nakamura, M. Nakao, H. Nakayama, A. Narimani Charan, M. Naruki, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, C. Niebuhr, N. K. Nisar, S. Nishida, K. Nishimura, H. Ono, P. Oskin, E. R. Oxford, G. Pakhlova, A. Paladino, A. Panta, E. Paoloni, S. Pardi, K. Parham, H. Park, S. -H. Park, A. Passeri, T. K. Pedlar, I. Peruzzi, R. Peschke, R. Pestotnik, F. Pham, L. E. Piilonen, G. Pinna Angioni, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, L. Polat, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, N. Rad, P. Rados, S. Raiz, M. Reif, S. Reiter, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, A. Sangal, L. Santelj, Y. Sato, V. Savinov, B. Scavino, C. Schwanda, A. J. Schwartz, Y. Seino, A. Selce, K. Senyo, J. Serrano, C. Sfienti, C. P. Shen, T. Shillington, J. -G. Shiu, A. Sibidanov, F. Simon, R. J. Sobie, A. Soffer, A. Sokolov, E. Solovieva, S. Spataro, B. Spruck, M. Starič, S. Stefkova, R. Stroili, J. Strube, M. Sumihama, K. Sumisawa, W. Sutcliffe, S. Y. Suzuki, H. Svidras, M. Takahashi, M. Takizawa, U. Tamponi, S. Tanaka, K. Tanida, H. Tanigawa, N. Taniguchi, F. Tenchini, R. Tiwary, D. Tonelli, E. Torassa, N. Toutounji, K. Trabelsi, M. Uchida, K. Unger, Y. Unno, K. Uno, S. Uno, P. Urquijo, Y. Ushiroda, S. E. Vahsen, R. van Tonder, G. S. Varner, K. E. Varvell, A. Vinokurova, L. Vitale, V. Vobbilisetti, E. Waheed, H. M. Wakeling, E. Wang, M. -Z. Wang, X. L. Wang, A. Warburton, S. Watanuki, M. Welsch, C. Wessel, J. Wiechczynski, H. Windel, E. Won, X. P. Xu, B. D. Yabsley, S. Yamada, S. B. Yang, H. Ye, J. Yelton, J. H. Yin, K. Yoshihara, Y. Yusa, Y. Zhang, V. Zhilich, Q. D. Zhou, V. I. Zhukova, and R. Žlebčík, Abudinén, F., Aggarwal, L., Ahmed, H., Ahn, J. K., Aihara, H., Akopov, N., Aloisio, A., Anh Ky, N., Asner, D. M., Atmacan, H., Aushev, T., Aushev, V., Babu, V., Bae, H., Bambade, P., Banerjee, Sw., Bansal, S., Baudot, J., Bauer, M., Baur, A., Beaubien, A., Becker, J., Bennett, J. V., Bernieri, E., Bernlochner, F. U., Bertacchi, V., Bertemes, M., Bertholet, E., Bessner, M., Bettarini, S., Bhardwaj, V., Bianchi, F., Bilka, T., Biswas, D., Bodrov, D., Bolz, A., Bonvicini, G., Bozek, A., Bračko, M., Branchini, P., Briere, R. A., Browder, T. E., Budano, A., Bussino, S., Campajola, M., Cao, L., Casarosa, G., Cecchi, C., Chang, M. -C., Chang, P., Cheaib, R., Cheema, P., Chen, C., Chen, Y. Q., Chen, Y. -T., Cheon, B. G., Chilikin, K., Chirapatpimol, K., Cho, H. -E., Cho, K., Cho, S. -J., Choi, S. -K., Choudhury, S., Cinabro, D., Corona, L., Cremaldi, L. M., Cunliffe, S., Dattola, F., De La Cruz-Burelo, E., De La Motte, S. A., De Nardo, G., De Nuccio, M., De Pietro, G., de Sangro, R., Destefanis, M., De Yta-Hernandez, A., Dhamija, R., Di Canto, A., Di Capua, F., Dingfelder, J., Doležal, Z., Domínguez Jiménez, I., Dong, T. V., Dorigo, M., Dort, K., Dossett, D., Dreyer, S., Dujany, G., Eliachevitch, M., Epifanov, D., Feichtinger, P., Ferber, T., Ferlewicz, D., Fillinger, T., Finocchiaro, G., Flood, K., Fodor, A., Forti, F., Frey, A., Fulsom, B. G., Gabrielli, A., Ganiev, E., Garcia-Hernandez, M., Gaz, A., Gellrich, A., Ghevondyan, G., Giordano, R., Giri, A., Glazov, A., Gobbo, B., Godang, R., Goldenzweig, P., Gradl, W., Granderath, S., Greenwald, D., Gu, T., Guan, Y., Gudkova, K., Guilliams, J., Halder, S., Hara, K., Hartbrich, O., Hayasaka, K., Hayashii, H., Hazra, S., Hearty, C., Heredia de la Cruz, I., Hernández Villanueva, M., Hershenhorn, A., Higuchi, T., Hohmann, M., Humair, T., Iijima, T., Inami, K., Inguglia, G., Ipsita, N., Ishikawa, A., Ito, S., Itoh, R., Iwasaki, M., Iwasaki, Y., Jackson, P., Jacobs, W. W., Jaffe, D. E., Ji, Q. P., Jin, Y., Junkerkalefeld, H., Kaleta, M., Kandra, J., Kang, K. H., Karl, R., Karyan, G., Kiesling, C., Kim, C. -H., Kim, D. Y., Kim, K. -H., Kim, Y. -K., Kindo, H., Kinoshita, K., Kodyš, P., Koga, T., Kohani, S., Kojima, K., Korobov, A., Korpar, S., Kovalenko, E., Kowalewski, R., Kraetzschmar, T. M. G., Križan, P., Krokovny, P., Kuhr, T., Kumar, J., Kumar, R., Kumara, K., Kunigo, T., Kwon, Y. -J., Lacaprara, S., Lam, T., Lanceri, L., Lange, J. S., Laurenza, M., Leboucher, R., Lee, S. C., Leitl, P., Levit, D., Li, L. K., Li, S. X., Li, Y. B., Libby, J., Liptak, Z., Liu, Q. Y., Liventsev, D., Longo, S., Lueck, T., Lyu, C., Maggiora, M., Maiti, R., Maity, S., Manfredi, R., Manoni, E., Marcello, S., Marinas, C., Martel, L., Martini, A., Massaccesi, L., Masuda, M., Matsuoka, K., Matvienko, D., Mckenna, J. A., Meier, F., Merola, M., Milesi, M., Miller, C., Miyabayashi, K., Mohanty, G. B., Molina-Gonzalez, N., Moneta, S., Moon, H., Moser, H. -G., Mrvar, M., Mussa, R., Nakamura, I., Nakao, M., Nakayama, H., Narimani Charan, A., Naruki, M., Natkaniec, Z., Natochii, A., Nayak, L., Nayak, M., Nazaryan, G., Niebuhr, C., Nisar, N. K., Nishida, S., Nishimura, K., Ono, H., Oskin, P., Oxford, E. R., Pakhlova, G., Paladino, A., Panta, A., Paoloni, E., Pardi, S., Parham, K., Park, H., Park, S. -H., Passeri, A., Pedlar, T. K., Peruzzi, I., Peschke, R., Pestotnik, R., Pham, F., Piilonen, L. E., Pinna Angioni, G., Podesta-Lerma, P. L. M., Podobnik, T., Pokharel, S., Polat, L., Praz, C., Prell, S., Prencipe, E., Prim, M. T., Purwar, H., Rad, N., Rados, P., Raiz, S., Reif, M., Reiter, S., Ripp-Baudot, I., Rizzo, G., Robertson, S. H., Roney, J. M., Rostomyan, A., Rout, N., Russo, G., Sanders, D. A., Sandilya, S., Sangal, A., Santelj, L., Sato, Y., Savinov, V., Scavino, B., Schwanda, C., Schwartz, A. J., Seino, Y., Selce, A., Senyo, K., Serrano, J., Sfienti, C., Shen, C. P., Shillington, T., Shiu, J. -G., Sibidanov, A., Simon, F., Sobie, R. J., Soffer, A., Sokolov, A., Solovieva, E., Spataro, S., Spruck, B., Starič, M., Stefkova, S., Stroili, R., Strube, J., Sumihama, M., Sumisawa, K., Sutcliffe, W., Suzuki, S. Y., Svidras, H., Takahashi, M., Takizawa, M., Tamponi, U., Tanaka, S., Tanida, K., Tanigawa, H., Taniguchi, N., Tenchini, F., Tiwary, R., Tonelli, D., Torassa, E., Toutounji, N., Trabelsi, K., Uchida, M., Unger, K., Unno, Y., Uno, K., Uno, S., Urquijo, P., Ushiroda, Y., Vahsen, S. E., van Tonder, R., Varner, G. S., Varvell, K. E., Vinokurova, A., Vitale, L., Vobbilisetti, V., Waheed, E., Wakeling, H. M., Wang, E., Wang, M. -Z., Wang, X. L., Warburton, A., Watanuki, S., Welsch, M., Wessel, C., Wiechczynski, J., Windel, H., Won, E., Xu, X. P., Yabsley, B. D., Yamada, S., Yang, S. B., Ye, H., Yelton, J., Yin, J. H., Yoshihara, K., Yusa, Y., Zhang, Y., Zhilich, V., Zhou, Q. D., Zhukova, V. I., and Žlebčík, and R.

Abstract

An absolute measurement of the Λ_{c}^{+} lifetime is reported using Λ_{c}^{+}→pK^{-}π^{+} decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the ϒ(4S) resonance, is 207.2 fb^{-1}. The result, τ(Λ_{c}^{+})=203.20±0.89±0.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.

Published
2023

15. {Measurement of the \ensuremath{\Omega}c0 lifetime at Belle II}

Author

F. Abudinén, I. Adachi, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, A. Aloisio, N. Anh Ky, D. M. Asner, T. Aushev, V. Aushev, H. Bae, P. Bambade, Sw. Banerjee, J. Baudot, M. Bauer, A. Beaubien, J. Becker, P. K. Behera, J. V. Bennett, E. Bernieri, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, T. Bilka, D. Biswas, D. Bodrov, A. Bolz, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, M. -C. Chang, P. Cheema, V. Chekelian, Y. Q. Chen, K. Chilikin, K. Chirapatpimol, H. -E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, S. Choudhury, D. Cinabro, L. Corona, S. Cunliffe, S. Das, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, M. De Nuccio, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. De Yta-Hernandez, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, S. Dreyer, S. Dubey, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, G. Finocchiaro, A. Fodor, F. Forti, B. G. Fulsom, E. Ganiev, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, R. Giordano, A. Giri, A. Glazov, B. Gobbo, R. Godang, P. Goldenzweig, W. Gradl, S. Granderath, E. Graziani, D. Greenwald, T. Gu, Y. Guan, K. Gudkova, J. Guilliams, K. Hayasaka, H. Hayashii, S. Hazra, C. Hearty, I. Heredia de la Cruz, M. Hernández Villanueva, A. Hershenhorn, T. Higuchi, E. C. Hill, H. Hirata, M. Hohmann, C. -L. Hsu, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, S. Ito, R. Itoh, M. Iwasaki, P. Jackson, W. W. Jacobs, D. E. Jaffe, E. -J. Jang, S. Jia, Y. Jin, K. K. Joo, H. Junkerkalefeld, A. B. Kaliyar, K. H. Kang, R. Karl, G. Karyan, C. Kiesling, C. -H. Kim, D. Y. Kim, K. -H. Kim, Y. -K. Kim, H. Kindo, K. Kinoshita, P. Kodyš, T. Koga, S. Kohani, K. Kojima, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, R. Kowalewski, T. M. G. Kraetzschmar, P. Križan, P. Krokovny, J. Kumar, K. Kumara, T. Kunigo, A. Kuzmin, Y. -J. Kwon, S. Lacaprara, T. Lam, L. Lanceri, J. S. Lange, M. Laurenza, K. Lautenbach, R. Leboucher, C. Li, L. K. Li, J. Libby, K. Lieret, Z. Liptak, Q. Y. Liu, D. Liventsev, S. Longo, A. Lozar, T. Lueck, C. Lyu, M. Maggiora, R. Maiti, R. Manfredi, E. Manoni, S. Marcello, C. Marinas, A. Martini, T. Martinov, L. Massaccesi, M. Masuda, S. K. Maurya, J. A. McKenna, F. Meier, M. Merola, F. Metzner, M. Milesi, C. Miller, K. Miyabayashi, R. Mizuk, G. B. Mohanty, N. Molina-Gonzalez, S. Moneta, H. -G. Moser, M. Mrvar, R. Mussa, I. Nakamura, M. Nakao, H. Nakayama, Y. Nakazawa, A. Narimani Charan, M. Naruki, Z. Natkaniec, A. Natochii, L. Nayak, M. Nayak, G. Nazaryan, N. K. Nisar, S. Ogawa, H. Ono, Y. Onuki, E. R. Oxford, A. Paladino, A. Panta, E. Paoloni, S. Pardi, H. Park, S. -H. Park, A. Passeri, S. Paul, T. K. Pedlar, I. Peruzzi, R. Peschke, R. Pestotnik, M. Piccolo, L. E. Piilonen, P. L. M. Podesta-Lerma, T. Podobnik, S. Pokharel, L. Polat, C. Praz, S. Prell, E. Prencipe, M. T. Prim, H. Purwar, N. Rad, P. Rados, S. Raiz, A. Ramirez Morales, M. Reif, S. Reiter, M. Remnev, I. Ripp-Baudot, G. Rizzo, S. H. Robertson, J. M. Roney, A. Rostomyan, N. Rout, G. Russo, D. A. Sanders, S. Sandilya, A. Sangal, Y. Sato, V. Savinov, B. Scavino, J. Schueler, C. Schwanda, A. J. Schwartz, B. Schwenker, Y. Seino, A. Selce, K. Senyo, J. Serrano, M. E. Sevior, C. Sfienti, C. P. Shen, X. D. Shi, T. Shillington, A. Sibidanov, J. B. Singh, J. Skorupa, R. J. Sobie, A. Soffer, E. Solovieva, S. Spataro, B. Spruck, M. Starič, S. Stefkova, Z. S. Stottler, R. Stroili, J. Strube, M. Sumihama, K. Sumisawa, W. Sutcliffe, S. Y. Suzuki, H. Svidras, M. Takizawa, U. Tamponi, K. Tanida, H. Tanigawa, F. Tenchini, A. Thaller, R. Tiwary, D. Tonelli, E. Torassa, N. Toutounji, K. Trabelsi, M. Uchida, I. Ueda, Y. Uematsu, T. Uglov, K. Unger, Y. Unno, K. Uno, S. Uno, Y. Ushiroda, S. E. Vahsen, R. van Tonder, G. S. Varner, K. E. Varvell, A. Vinokurova, L. Vitale, V. Vobbilisetti, H. M. Wakeling, E. Wang, M. -Z. Wang, X. L. Wang, A. Warburton, M. Watanabe, S. Watanuki, M. Welsch, C. Wessel, E. Won, B. D. Yabsley, S. Yamada, W. Yan, S. B. Yang, H. Ye, J. Yelton, J. H. Yin, Y. M. Yook, K. Yoshihara, C. Z. Yuan, L. Zani, Y. Zhang, V. Zhilich, Q. D. Zhou, X. Y. Zhou, V. I. Zhukova, and R. Žlebčík, Abudinén, F., Adachi, I., Aggarwal, L., Ahmed, H., Aihara, H., Akopov, N., Aloisio, A., Anh Ky, N., Asner, D. M., Aushev, T., Aushev, V., Bae, H., Bambade, P., Banerjee, Sw., Baudot, J., Bauer, M., Beaubien, A., Becker, J., Behera, P. K., Bennett, J. V., Bernieri, E., Bernlochner, F. U., Bertacchi, V., Bertemes, M., Bertholet, E., Bessner, M., Bettarini, S., Bhuyan, B., Bianchi, F., Bilka, T., Biswas, D., Bodrov, D., Bolz, A., Borah, J., Bozek, A., Bračko, M., Branchini, P., Briere, R. A., Browder, T. E., Budano, A., Bussino, S., Campajola, M., Cao, L., Casarosa, G., Cecchi, C., Chang, M. -C., Cheema, P., Chekelian, V., Chen, Y. Q., Chilikin, K., Chirapatpimol, K., Cho, H. -E., Cho, K., Cho, S. -J., Choi, S. -K., Choudhury, S., Cinabro, D., Corona, L., Cunliffe, S., Das, S., Dattola, F., De La Cruz-Burelo, E., De La Motte, S. A., de Marino, G., De Nardo, G., De Nuccio, M., De Pietro, G., de Sangro, R., Destefanis, M., Dey, S., De Yta-Hernandez, A., Dhamija, R., Di Canto, A., Di Capua, F., Dingfelder, J., Doležal, Z., Domínguez Jiménez, I., Dong, T. V., Dorigo, M., Dort, K., Dreyer, S., Dubey, S., Dujany, G., Ecker, P., Eliachevitch, M., Epifanov, D., Feichtinger, P., Ferber, T., Ferlewicz, D., Fillinger, T., Finocchiaro, G., Fodor, A., Forti, F., Fulsom, B. G., Ganiev, E., Gaur, V., Gaz, A., Gellrich, A., Ghevondyan, G., Giordano, R., Giri, A., Glazov, A., Gobbo, B., Godang, R., Goldenzweig, P., Gradl, W., Granderath, S., Graziani, E., Greenwald, D., Gu, T., Guan, Y., Gudkova, K., Guilliams, J., Hayasaka, K., Hayashii, H., Hazra, S., Hearty, C., Heredia de la Cruz, I., Hernández Villanueva, M., Hershenhorn, A., Higuchi, T., Hill, E. C., Hirata, H., Hohmann, M., Hsu, C. -L., Iijima, T., Inami, K., Inguglia, G., Ipsita, N., Ishikawa, A., Ito, S., Itoh, R., Iwasaki, M., Jackson, P., Jacobs, W. W., Jaffe, D. E., Jang, E. -J., Jia, S., Jin, Y., Joo, K. K., Junkerkalefeld, H., Kaliyar, A. B., Kang, K. H., Karl, R., Karyan, G., Kiesling, C., Kim, C. -H., Kim, D. Y., Kim, K. -H., Kim, Y. -K., Kindo, H., Kinoshita, K., Kodyš, P., Koga, T., Kohani, S., Kojima, K., Konno, T., Korobov, A., Korpar, S., Kovalenko, E., Kowalewski, R., Kraetzschmar, T. M. G., Križan, P., Krokovny, P., Kumar, J., Kumara, K., Kunigo, T., Kuzmin, A., Kwon, Y. -J., Lacaprara, S., Lam, T., Lanceri, L., Lange, J. S., Laurenza, M., Lautenbach, K., Leboucher, R., Li, C., Li, L. K., Libby, J., Lieret, K., Liptak, Z., Liu, Q. Y., Liventsev, D., Longo, S., Lozar, A., Lueck, T., Lyu, C., Maggiora, M., Maiti, R., Manfredi, R., Manoni, E., Marcello, S., Marinas, C., Martini, A., Martinov, T., Massaccesi, L., Masuda, M., Maurya, S. K., Mckenna, J. A., Meier, F., Merola, M., Metzner, F., Milesi, M., Miller, C., Miyabayashi, K., Mizuk, R., Mohanty, G. B., Molina-Gonzalez, N., Moneta, S., Moser, H. -G., Mrvar, M., Mussa, R., Nakamura, I., Nakao, M., Nakayama, H., Nakazawa, Y., Narimani Charan, A., Naruki, M., Natkaniec, Z., Natochii, A., Nayak, L., Nayak, M., Nazaryan, G., Nisar, N. K., Ogawa, S., Ono, H., Onuki, Y., Oxford, E. R., Paladino, A., Panta, A., Paoloni, E., Pardi, S., Park, H., Park, S. -H., Passeri, A., Paul, S., Pedlar, T. K., Peruzzi, I., Peschke, R., Pestotnik, R., Piccolo, M., Piilonen, L. E., Podesta-Lerma, P. L. M., Podobnik, T., Pokharel, S., Polat, L., Praz, C., Prell, S., Prencipe, E., Prim, M. T., Purwar, H., Rad, N., Rados, P., Raiz, S., Ramirez Morales, A., Reif, M., Reiter, S., Remnev, M., Ripp-Baudot, I., Rizzo, G., Robertson, S. H., Roney, J. M., Rostomyan, A., Rout, N., Russo, G., Sanders, D. A., Sandilya, S., Sangal, A., Sato, Y., Savinov, V., Scavino, B., Schueler, J., Schwanda, C., Schwartz, A. J., Schwenker, B., Seino, Y., Selce, A., Senyo, K., Serrano, J., Sevior, M. E., Sfienti, C., Shen, C. P., Shi, X. D., Shillington, T., Sibidanov, A., Singh, J. B., Skorupa, J., Sobie, R. J., Soffer, A., Solovieva, E., Spataro, S., Spruck, B., Starič, M., Stefkova, S., Stottler, Z. S., Stroili, R., Strube, J., Sumihama, M., Sumisawa, K., Sutcliffe, W., Suzuki, S. Y., Svidras, H., Takizawa, M., Tamponi, U., Tanida, K., Tanigawa, H., Tenchini, F., Thaller, A., Tiwary, R., Tonelli, D., Torassa, E., Toutounji, N., Trabelsi, K., Uchida, M., Ueda, I., Uematsu, Y., Uglov, T., Unger, K., Unno, Y., Uno, K., Uno, S., Ushiroda, Y., Vahsen, S. E., van Tonder, R., Varner, G. S., Varvell, K. E., Vinokurova, A., Vitale, L., Vobbilisetti, V., Wakeling, H. M., Wang, E., Wang, M. -Z., Wang, X. L., Warburton, A., Watanabe, M., Watanuki, S., Welsch, M., Wessel, C., Won, E., Yabsley, B. D., Yamada, S., Yan, W., Yang, S. B., Ye, H., Yelton, J., Yin, J. H., Yook, Y. M., Yoshihara, K., Yuan, C. Z., Zani, L., Zhang, Y., Zhilich, V., Zhou, Q. D., Zhou, X. Y., Zhukova, V. I., and Žlebčík, and R.

Published
2023

16. A DAQ Upgrade Solution for Belle II Experiment

Author

R. Itoh, Zhen'An Liu, Jingzhou Zhao, Satoru Yamada, Hanjun Kou, Jianing Song, Q. D. Zhou, Pengcheng Cao, Wenxuan Gong, and Jia Tao

Subjects
Ethernet, Nuclear and High Energy Physics, 010308 nuclear & particles physics, business.industry, Computer science, Firmware, Reconfigurability, computer.software_genre, 01 natural sciences, Data acquisition, Upgrade, Nuclear Energy and Engineering, Advanced Mezzanine Card, 0103 physical sciences, Scalability, Bandwidth (computing), Electrical and Electronic Engineering, business, computer, Computer hardware
Abstract

While the current Belle II data acquisition (DAQ) system has proven to be reliable in the first collisions delivered since May 2018, an upgrade to increase the bandwidth of the readout system is foreseen to be deployed over the next few years for higher target luminosity SuperKEKB running. Currently, the front-end electronics (FEE) of individual subdetectors are connected to the online event building system via a unified optical link called Belle2Link, offering unidirectional data readout as well as bidirectional slow control access. The FEE data are received by high-speed link boards (HSLB) and common pipelined platform for electronics readout (COPPER) boards collecting data from up to four links, forwarding to readout PCs (ROPC), which further aggregate the data and forward the data to the event builder. It is planned to keep the Belle2Link and subsystems FEE as they are, but to replace the HSLB/COPPER (including the back-end side of Belle2link) and ROPC with an upgraded high-density system with increased throughput and processing capabilities, to enable the operation at higher rates. This article presents a solution for this upgrade based on the xTCA-for-Physics (MicroTCA)-compatible concentration preprocessing and fan-out plus (CPPF+) board featuring significant data concentration and processing power, providing up to 40-Gb Ethernet output bandwidth. Belle2Link back-end firmware and subevent building are implemented in the CPPF+ board to deliver equivalent functionality as the COPPER/ROPC. The MicroTCA platform provides scalability, reconfigurability, and reliable operations, even for a future possible increase in bandwidth and potential FEE upgrades. A fully functional demonstration readout system has been constructed and verified with the time-of-propagation (TOP) detector front-end test bench set up at KEK in terms of functionality as well as performance. Results show that this solution fulfills the requirements of the DAQ upgrade and works stably and reliably in long-term tests.

Published
2020

17. Trigger Timing Interface for the Read-Out Upgrade of the Belle II DAQ

Author

D. Levit, M. Bessner, D. Biswas, D. Charlet, O. Hartbrich, T. Higuchi, R. Itoh, E. Jules, P. Kapusta, T. Kunigo, Y.-T. Lai, T. S. Lau, M. Nakao, K. Nishimura, S.-H. Park, E. Plaige, H. Purwar, P. Robbe, R. Sugiura, S. Suzuki, M. Taurigna, G. Varner, S. Yamada, and Q.-D. Zhou

Subjects
Nuclear and High Energy Physics, Nuclear Energy and Engineering, Electrical and Electronic Engineering
Published
2023

18. Precise Measurement of the D0 and D+ Lifetimes at Belle II

Author

R. Mussa, F. Pham, H. Svidras, T. Lam, A. Ishikawa, L. E. Piilonen, M. Nakao, P. Križan, K. Yoshihara, Concettina Sfienti, P. Oskin, U. Tamponi, M. Iwasaki, T. Iijima, A. Kuzmin, M. Welsch, T. M. G. Kraetzschmar, E.-J. Jang, B. G. Cheon, S. Ogawa, G. Giakoustidis, H. Ono, L. M. Cremaldi, K. Matsuoka, T. Kuhr, G. L. Pinna Angioni, S. E. Vahsen, I. Ueda, S. Pardi, N. Rad, M. Bračko, A. Gabrielli, Antonio Budano, Y. Iwasaki, Y. J. Kwon, J. F. Strube, S. Kohani, L. Lanceri, S. Uehara, Makoto Tabata, Jakub Kandra, N. Rout, P. Leitl, T. V. Dong, W. Gradl, K. Flood, C. Niebuhr, X. Y. Zhou, S. Sandilya, M. Starič, M. Hernandez Villanueva, Hidekazu Kakuno, S. Y. Suzuki, L. Corona, R. Stroili, M. Remnev, S. Baehr, E. Wang, F. Meier, I. Ripp-Baudot, Shih-Chang Lee, S. Pokharel, R. Itoh, S. Jia, Dipak Kumar Sahoo, D. Bodrov, P. Bambade, Luka Santelj, Bruce Yabsley, T. Matsuda, Enrico Bernieri, S. Uno, H. Junkerkalefeld, L. Aggarwal, Sunil Bansal, Y. Unno, C. Murphy, C. Wessel, M. Niiyama, Rok Pestotnik, D. Biswas, T. Tsuboyama, F. Abudinén, M. Piccolo, Takeo Higuchi, Carlos Marinas, J. M. Roney, J. Libby, D. M. Asner, S. Halder, K. Hayasaka, R. Tiwary, C. Miller, C. H. Kim, F. Di Capua, T. Koga, A. B. Kaliyar, A. Pathak, K. Tanida, G. Dujany, H. G. Moser, T. Bilka, Daniel Greenwald, F. Tenchini, S. Prell, Seema Bahinipati, Andrey Sokolov, T. Uglov, B. Paschen, G. De Pietro, B. Shwartz, Y. Uematsu, M. Takizawa, Yu. Onishchuk, A. Vinokurova, S. Dubey, I. Heredia-De La Cruz, K. Hara, Y. Seino, H. Tanigawa, B. Golob, M. Bertemes, C.-L. Hsu, M. Watanabe, H. Ozaki, T. E. Browder, A. Glazov, O. Hartbrich, J. Schueler, M. T. Prim, Takeo Kawasaki, D. Y. Kim, Dmytro Levit, A. Natochii, J. Baudot, C. H. Li, K. Lieret, K. Inami, V. Zhukova, Y. Onuki, A. Fodor, Kouji Nakamura, S. Bilokin, R. Žlebčík, A. Baur, P. Krokovny, Sw. Banerjee, John Yelton, S. Stefkova, Q. D. Zhou, D. Cinabro, R. Giordano, Shuji Tanaka, E. C. Hill, Hamad Ahmed, Q. Y. Liu, M. Dorigo, E. Kovalenko, K. Unger, P. Pakhlov, Rakesh Kumar, T. Podobnik, A. J. Schwartz, Z. Doležal, G. Inguglia, G. Nazaryan, P. Chang, M. Kumar, I. Domínguez Jiménez, V. Bhardwaj, Z. Liptak, E. Bertholet, I. Adachi, F. Forti, M. Mrvar, J. Serrano, H. Ye, M. Barrett, E. Won, K. H. Kang, K. Cho, N. Molina-Gonzalez, A. Passeri, L. Zani, G. Polat, R. Kowalewski, K. Trabelsi, J. Guilliams, G. Finocchiaro, J. Bennett, A. Sangal, G. Casarosa, C. Praz, T. Gu, M. Z. Wang, K. Kinoshita, Peter Kodys, W. W. Jacobs, M. Bessner, G. S. Varner, A. Gellrich, S. Raiz, Abner Soffer, Elisa Manoni, K. Chirapatpimol, S. Reiter, N. Gabyshev, D. Červenkov, Nils Braun, T. Czank, S. Cunliffe, P. L. M. Podesta-Lerma, B. Spruck, I. M. Peruzzi, R. de Sangro, D. Epifanov, M. Campajola, H. Purwar, A. Selce, E. Solovieva, T. Lueck, A. Bolz, Somnath Choudhury, T. Hara, H. Aihara, K. Lautenbach, A. Panta, M. Merola, J. G. Shiu, Y.-T. Chen, Samo Korpar, Claudia Cecchi, G. de Marino, A. Rostomyan, A. Paladino, M. C. Chang, S. Bussino, V.N. Zhilich, L. B. Rizzuto, Agnese Martini, F. Bianchi, Y. Ushiroda, N. Toutounji, Jürgen Becker, S. Yamada, R. Manfredi, Hitoshi Hirata, Y. Kato, D. Ferlewicz, H. Nakazawa, P. Branchini, S. Bettarini, Yu. V. Usov, W. Sutcliffe, J. H. Yin, B. G. Fulsom, Florian Urs Bernlochner, S. Nishida, G. Karyan, A. Di Canto, Jochen Dingfelder, K. Senyo, H. M. Wakeling, J. Wiechczynski, T. K. Pedlar, K. Uno, Andreas Warburton, C. Kiesling, W. B. Yan, D. A. Sanders, Phillip Urquijo, R. Godang, Ya-Qiu Jin, G. De Nardo, D. Tonelli, R. Mizuk, M. Sumihama, C. H. Chen, Z. Natkaniec, A. Vossen, S. K. Choi, L. K. Li, E. R. Oxford, K. Miyabayashi, S. Duell, R. Peschke, E. Paoloni, K. Nishimura, Frank Simon, Seongbae Yang, N. Taniguchi, C. Hearty, Y. Guan, Prafulla Kumar Behera, M. Destefanis, M. Hoek, Matthias Bauer, R. Cheaib, K. Kumara, S. Spataro, X. P. Xu, E. Prencipe, M. Rozanska, H. Hayashii, Z. S. Stottler, A. K. Giri, R. J. Sobie, D. Matvienko, L. Vitale, N. K. Nisar, H. K. Moon, J. Kumar, S.-H. Park, J. S. Lange, C. Hadjivasiliou, R. Karl, T. D. Kimmel, Stefano Longo, T. Pang, S. Patra, A. Sibidanov, K. Adamczyk, F. Dattola, L. Cao, A. Bobrov, D. Liventsev, F. R. Le Diberder, Yongsun Kim, B. Gobbo, K. Lalwani, P. Goldenzweig, N. Anh Ky, E. Graziani, E. De La Cruz-Burelo, H. E. Cho, C. Schwanda, F. Krinner, E. Torassa, Pere Rados, M. V. Purohit, R. A. Briere, I. Nakamura, K. Chilikin, D. E. Jaffe, T. Humair, P. Ecker, M. Hohmann, E. Waheed, V. Aushev, Tomoyuki Konno, D. Dossett, C. Lyu, S.-J. Cho, A. De Yta-Hernandez, J. A. McKenna, Y. Kim, V. Babu, T. Ferber, S. Kurz, V. Popov, S. Dey, A. Hershenhorn, G. Rizzo, S. Lacaprara, N. Akopov, Soumen Paul, Felix Metzner, B. Scavino, H. Atmacan, G. B. Mohanty, Alberto Aloisio, Y. Yusa, Yuki Sato, M. Laurenza, V. Savinov, S. Bacher, K. Dort, H. Park, A. Bozek, K. Gudkova, Alessandro Gaz, S. H. Robertson, X. L. Wang, V. Chekelian, S. Hazra, R. Van Tonder, and H. Bae

Subjects
Physics, Particle physics, 010308 nuclear & particles physics, law, 0103 physical sciences, General Physics and Astronomy, Resonance, 010306 general physics, Collider, 01 natural sciences, law.invention, Luminosity
Abstract

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72 fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst) fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst) fs, are the most precise to date and are consistent with previous determinations.

Published
2021

19. Search for B+→K+νν¯ Decays Using an Inclusive Tagging Method at Belle II

Author

T. Pang, S. Patra, A. Pathak, K. Adamczyk, G.V. Russo, J. Libby, D. M. Asner, T. Matsuda, Enrico Bernieri, K. Hayasaka, T. V. Dong, Tomoyuki Konno, E. Kovalenko, L. Zani, S. Fiore, F. R. Le Diberder, C. Lyu, A. Vinokurova, S. Dubey, I. Heredia-De La Cruz, P. Grace, J. Baudot, C. H. Li, I. M. Peruzzi, S.-J. Cho, Y. Seino, A. De Yta-Hernandez, O. Hartbrich, Y. Ushiroda, C. Niebuhr, X. Y. Zhou, B. Wach, H. Windel, E. Graziani, E. De La Cruz-Burelo, M. T. Prim, D. Liventsev, P. Krokovny, Rakesh Kumar, C. La Licata, B.A. Shwartz, Takeo Kawasaki, F. Bianchi, H. M. Wakeling, L. E. Piilonen, I. Domínguez Jiménez, Hitoshi Hirata, K. H. Kang, K. Cho, P. Oskin, Agnese Martini, S. Sandilya, A. Kuzmin, M. Welsch, R. Mizuk, E. Ganiev, P. Taras, D. Biswas, A. B. Kaliyar, T. Iijima, C. W. Joo, A. Sangal, T. M. G. Kraetzschmar, S. Stefkova, M. Starič, M. Z. Wang, Andrey Sokolov, Nils Braun, K. Matsuoka, T. Kuhr, Y.-T. Lai, S. Ogawa, D. Cinabro, R. Giordano, A. Baur, H. Ye, J. Schueler, M. E. Sevior, Claudia Cecchi, A. Panta, M. Merola, W. Gradl, P. L. M. Podesta-Lerma, Antonio Budano, K. Chilikin, N. Akopov, G. Inguglia, G. Nazaryan, T. Kunigo, C. Ketter, P. Goldenzweig, A. Gaz, A. Korobov, P. Chang, M. Kumar, M. De Nuccio, K. Nishimura, Frank Simon, R. M. Seddon, D. E. Jaffe, Abner Soffer, N. Anh Ky, H. Ozaki, V. Babu, K. Senyo, S. H. Robertson, S. Nishida, C. H. Chen, S. E. Vahsen, A. J. Schwartz, Kazuhiko Hara, A. Frey, D. Epifanov, Marco Milesi, M. Hernandez Villanueva, G. Finocchiaro, Dipak Kumar Sahoo, P. Bambade, K. Tanida, Y. M. Yook, J. Serrano, T. Ferber, S. Cunliffe, X. L. Wang, Yizeng Li, A. Di Canto, S. Bussino, Sunil Bansal, J. Bennett, Andreas Warburton, Y. Iwasaki, F. Abudinén, Y. J. Kwon, Somnath Choudhury, Tagir Aushev, S. Kurz, Semen Eidelman, S. Pardi, S. Spataro, T. Humair, K. Nakamura, V. Zhukova, Y. Onuki, Makoto Tabata, V. Chekelian, D. Rodríguez Pérez, G. De Nardo, S. Y. Suzuki, S. Hazra, T. K. Pedlar, N. Taniguchi, M. Takizawa, J. G. Shiu, R. Mussa, Jakub Kandra, M. Campajola, N. Rout, X. P. Xu, B. Paschen, Paul Jackson, Y.-T. Chen, Soumen Paul, M. Uchida, Felix Metzner, A. Gellrich, S. Raiz, H. Svidras, A. Garmash, C. Hadjivasiliou, Daniel Greenwald, John Yelton, L. K. Li, R. Van Tonder, M. Hohmann, A. Lozar, Z. Doležal, A. Natochii, A. Ishikawa, K. Inami, N. Toutounji, N. Rad, R. Pestotnik, E. Paoloni, M. Nakao, Stefano Longo, F. Tenchini, I. Ripp-Baudot, F. Meier, P. Križan, M. Remnev, H. Miyake, C.-L. Hsu, L. Cao, B. Scavino, D. A. Sanders, D. Matvienko, J. Wiechczynski, Seongbae Yang, H. Tanigawa, T. Podobnik, B. Spruck, K. Dort, B. Golob, Melissa K. Takahashi, S. Prell, S. Bettarini, Bruce Yabsley, Shih-Chang Lee, S. Duell, C. Miller, C. Hearty, E. Prencipe, Q. Y. Liu, P. Ahlburg, Martin Ritter, Dmytro Levit, M. Maggiora, Phillip Urquijo, N. K. Nisar, K. Lieret, K. Trabelsi, C. H. Kim, Z. Liptak, E. C. Hill, H. Park, S. X. Li, A. Bozek, W. A. T. Wan Abdullah, H. G. Moser, H. Atmacan, D. J. Summers, J. S. Lange, K. Uno, T. Koga, A. Selce, A. Passeri, M. Piccolo, Peter Kodys, R. Karl, T. D. Kimmel, E. Waheed, V.N. Zhilich, V. Aushev, Carlos Marinas, W. W. Jacobs, M. Bertemes, D. Ferlewicz, H. Hayashii, W. Sutcliffe, Elisa Manoni, R. J. Sobie, John Webb, L. Vitale, K. Chirapatpimol, M. Eliachevitch, J. Kumar, S.-H. Park, Yuki Sato, V. Popov, C. Z. Yuan, L. Santelj, S. Dey, K. Miyabayashi, Y. Guan, A. Paladino, R. Manfredi, E. Solovieva, T. Lueck, A. Sibidanov, A. Glazov, M. Laurenza, L. B. Rizzuto, G. de Marino, G. S. Varner, A. Hershenhorn, J. H. Yin, R. Cheaib, P. Branchini, G. Karyan, K. Kumara, Florian Urs Bernlochner, K. Gudkova, S. Lacaprara, V. Savinov, C. Kiesling, R. de Sangro, Z. S. Stottler, G. B. Mohanty, Alberto Aloisio, F. Krinner, A. K. Giri, Y. Yusa, S. Marcello, S. Baehr, G. Rizzo, M. Bračko, M. Destefanis, R. Itoh, K. Yoshihara, Concettina Sfienti, M. Masuda, G. Dujany, M. Iwasaki, F. Dattola, Sw. Banerjee, Satoshi Tanaka, E. Torassa, B. G. Cheon, L. M. Cremaldi, C. Murphy, C. Wessel, N. Gabyshev, D. Červenkov, A. Rostomyan, S. Korpar, F. Forti, M. Mrvar, B. G. Fulsom, R. Godang, S. Watanuki, Prafulla Kumar Behera, K. Sumisawa, S. Kohani, L. Corona, J. Irakkathil Jabbar, M. Garcia-Hernandez, G. Pakhlova, A. Fodor, H. Kichimi, Kevin Varvell, E. Bertholet, Takeo Higuchi, H. Aihara, F. Müller, Y. Usov, K. Lautenbach, Pere Rados, G. De Pietro, J. M. Roney, V. Gaur, M. Sumihama, C. Praz, M. Nayak, Ya-Qiu Jin, D. Tonelli, M. Hoek, Yongsun Kim, B. Gobbo, S. Uno, C. Schwanda, H. Ono, P. Leitl, R. Stroili, Y. Unno, D. Y. Kim, Q. D. Zhou, Iki Adachi, G. Polat, T. Fillinger, S. Pokharel, F. Di Capua, Y. Onishchuk, P. Pakhlov, P. Lewis, G. Casarosa, T. Czank, Jürgen Becker, S. Yamada, Jochen Dingfelder, W. B. Yan, Z. Natkaniec, U. Tamponi, M. Bessner, Surajit Maity, L. Lanceri, H. Junkerkalefeld, S. Halder, T. Bilka, and T. E. Browder

Subjects
Physics, Particle physics, Luminosity (scattering theory), 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, General Physics and Astronomy, Resonance, 01 natural sciences, law.invention, Pair production, law, 0103 physical sciences, High Energy Physics::Experiment, B meson, 010306 general physics, Collider, Energy (signal processing)
Abstract

A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb^{-1} collected at the ϒ(4S) resonance and a sample of 9 fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B^{+}→K^{+}νν[over ¯] of 4.1×10^{-5} is set at the 90% confidence level.

Published
2021

21. PCI-express based high-speed readout for the BelleII DAQ upgrade

Author

E. Plaige, Takuto Kunigo, G. S. Varner, R. Itoh, E. Jules, Takeo Higuchi, Kurtis Nishimura, D. Biswas, M. Taurigna, Satoru Yamada, Q. D. Zhou, Ryohei Sugiura, Y.-T. Lai, M. Nakao, D. Charlet, P. Robbe, P.J. Kapusta, O. Hartbrich, Martin Florian Bessner, S. Y. Suzuki, Harsh Purwar, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Computer science, Interface (computing), FOS: Physical sciences, data acquisition (DAQ), BELLE, DMA, computer.software_genre, 01 natural sciences, programming, High Energy Physics - Experiment, 030218 nuclear medicine & medical imaging, High Energy Physics - Experiment (hep-ex), 03 medical and health sciences, 0302 clinical medicine, Data acquisition, Gate array, 0103 physical sciences, PCI express, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], PCIe40, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Electrical and Electronic Engineering, Direct memory access, FPGA, PCI Express, 010308 nuclear & particles physics, business.industry, Firmware, Instrumentation and Detectors (physics.ins-det), trigger, Dead time, stability, Upgrade, Nuclear Energy and Engineering, efficiency, Index Terms-Belle II, electronics: readout, control system, business, computer, high-speed readout system, Computer hardware, data acquisition: upgrade, performance, electronics: design
Abstract

Belle II is a new-generation B-factory experiment, dedicated to exploring new physics beyond the standard model of elementary particles in the flavor sector. Belle II started data-taking in April 2018, using a synchronous data acquisition (DAQ) system based on pipelined trigger flow control. The Belle II DAQ system is designed to handle a 30-kHz trigger rate with approximately 1% of dead time, under the assumption of a raw event size of 1 MB. The DAQ system is reliable, and the overall data-taking efficiency reached 84.2% during the run period of January 2020–June 2020. The current readout system cannot be operated in the terms of ten years from the viewpoint of DAQ maintainability; meanwhile, the readout system is obstructing high-speed data transmission. A solution involving a peripheral component interconnect (PCI)-express-based readout module with high data throughput of up to 100 Gb/s was adopted to upgrade the Belle II DAQ system. We particularly focused on the design of firmware and software based on this new generation of readout board, called PCIe40, with an Altera Arria 10 field-programmable gate array chip. The 48-Gb transceiver (GBT) serial links, PCI-express hard IP-based direct memory access (DMA) architecture, interface of timing and trigger distribution system, and slow control system were designed to integrate with the current Belle II DAQ system. This article describes the performances accomplished during the data readout and slow control tests conducted using a test bench and a demonstration performed using on-site front-end electronics, specifically involving Belle II TOP and KLM subdetectors.

Published
2021

22. Design and performance of the Belle II High Level Trigger

Author

Nils Braun, S. Reiter, Markus Tobias Prim, S. Y. Suzuki, S. Yamada, Yinghui Guan, B. Spruck, R. Itoh, S-H Park, Jingzhou Zhao, Chunhua Li, Tomoyuki Konno, M. Nakao, K. Lautenbach, Oskar Hartbrich, Q. D. Zhou, and Z. A. Liu

Subjects
High level trigger, Luminosity (scattering theory), Computer science, Trigger rate, business.industry, Real-time computing, Detector, law.invention, Data flow diagram, Software, Data acquisition, law, Collider, business
Abstract

The data acquisition system of the Belle II detector is designed for a sustained first-level trigger rate of up to 30 kHz at the design luminosity of the SuperKEKB collider. The raw data read out from the subdetector frontends is delivered in realtime into an online High Level Trigger (HLT) farm, consisting of up to 20 computing nodes housing around 5000 processing cores, where it is reconstructed by the full Belle II reconstruction software in realtime. Based on this online reconstruction, events are filtered before being stored to disk for later offline processing and analysis. In this manuscript we will present the newly developed data flow throughout the HLT system utilizing the open-source library ZeroMQ, which was first used in the beam run period in fall 2019. Further, we show the performance of the HLT reconstruction and how the current setup scales with the anticipated future data rates when SuperKEKB increases its luminosity to the design value.

Published
2021
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23. Performance of the Unified Readout System of Belle II

Author

Tomoyuki Konno, Jingzhou Zhao, Hideyuki Nakazawa, T. Uchida, Nanae Taniguchi, Takuto Kunigo, A.S. Kuzmin, Hikaru Tanigawa, Dmytro Levit, Vladimir Zhulanov, R. Itoh, Y. Lai, Katsuro Nakamura, Kurtis Nishimura, Y. Unno, M. Nakao, Q. D. Zhou, Seokhee Park, S. Y. Suzuki, Satoru Yamada, Isar Mostafanezhad, Ryohei Sugiura, Masayoshi Shoji, Brandon Kunkler, Igor Konorov, Zhen'an Liu, and Oskar Hartbrich

Subjects
Physics, Nuclear and High Energy Physics, Luminosity (scattering theory), Physics - Instrumentation and Detectors, business.industry, Firmware, Detector, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), computer.software_genre, law.invention, Data link, Nuclear Energy and Engineering, law, Gate array, Electronics, Electrical and Electronic Engineering, Collider, business, Field-programmable gate array, computer, Computer hardware
Abstract

The Belle II experiment at the SuperKEKB collider at KEK, Tsukuba, Japan has successfully started taking data with the full detector in March 2019. Belle II is a luminosity frontier experiment of the new generation to search for physics beyond the Standard Model of elementary particles, from precision measurements of a huge number of B and charm mesons and tau leptons. In order to read out the events at a high rate from the seven subdetectors of Belle II, we adopt a highly unified readout system, including a unified trigger timing distribution system (TTD), a unified high speed data link system (Belle2link), and a common backend system to receive Belle2link data. Each subdetector frontend readout system has a field-programmable gate array (FPGA) in which unified firmware components of the TTD receiver and Belle2link transmitter are embedded. The system is designed for data taking at a trigger rate up to 30 kHz with a dead-time fraction of about 1% in the frontend readout system. The trigger rate is still much lower than our design. However, the background level is already high due to the initial vacuum condition and other accelerator parameters, and it is the most limiting factor of the accelerator and detector operation. Hence the occupancy and radiation effects to the frontend electronics are rather severe, and they cause various kind of instabilities. We present the performance of the system, including the achieved trigger rate, dead-time fraction, stability, and discuss the experience gained during the operation., IEEE Real Time 2020 Conference, 7 pages

Published
2020

24. Search for Axionlike Particles Produced in e+e− Collisions at Belle II

Author

C. Rosenfeld, R. M. Seddon, S. H. Robertson, H. Ye, S. Kohani, Martin Florian Bessner, Shuji Tanaka, R. Mussa, H. M. Wakeling, J. Serrano, R. Rasheed, H. Svidras, A. Ishikawa, M. Nakao, R. Mizuk, J. Bennett, Kevin Varvell, F. Meggendorfer, M. Reif, L. Zani, D. M. Asner, K. Hayasaka, X. L. Wang, K. Kumara, Z. S. Stottler, V. Chekelian, D. Rodríguez Pérez, K. Chilikin, Richard Peschke, A. Pathak, S. E. Vahsen, D. Tonelli, C. H. Li, E. De La Cruz-Burelo, P. Križan, Ashlie Martini, I. M. Peruzzi, M. De Nuccio, R. Van Tonder, C. H. Kim, H. Aihara, D. Greenwald, F. Müller, C. MacQueen, M. Takizawa, Claudia Cecchi, G. De Nardo, M. T. Hedges, P. Pakhlov, D. Matvienko, B. Spruck, Seokhee Park, Samo Korpar, S. Nishida, A. Sibidanov, Yukinori Sato, Carlos Marinas, M. Hoek, E. J. Jang, F. Bianchi, L. Santelj, Tao Luo, K. Dort, Hitoshi Hirata, Yoshinobu Unno, F. Tenchini, N. Akopov, J. G. Shiu, S. H. Kim, Yongsun Kim, K. Tanida, A. Gaz, J. Baudot, Z. Doležal, A. J. Schwartz, T. Sumiyoshi, C. Kleinwort, C. Wessel, V. Babu, H. Park, H. Nakazawa, B. Gobbo, H. Ono, Florian Urs Bernlochner, C. Schwanda, L. J. Wu, C. Kiesling, Martin Ritter, Dmytro Levit, Elisa Manoni, S. Jia, D. E. Jaffe, A. K. Giri, Abner Soffer, S. Marcello, Soumen Paul, Makoto Tabata, Jakub Kandra, Phillip Urquijo, M. Uchida, K. Chirapatpimol, S. Reiter, S. Watanuki, W. B. Yan, G. De Pietro, E. C. Hill, Semen Eidelman, Felix Metzner, K. Lieret, H. Windel, N. Rout, M. Masuda, B. Scavino, V. Gaur, G. Rizzo, P. Oskin, V. Bhardwaj, M. Bračko, M. Destefanis, L. Li Gioi, Michael Ritzert, T. E. Browder, Marco Milesi, M. Piccolo, E. Ganiev, T. Ferber, A. Garmash, L. Corona, S. J. Cho, M. Campajola, Tagir Aushev, S. Kurz, S. Wehle, U. Gebauer, S. Halder, Y. Ushiroda, Rocky Bala Garg, C. W. Joo, A. Gellrich, S. Bussino, C. Z. Yuan, P. Leitl, F. Dattola, T. V. Dong, D. Liventsev, H. Hayashii, V. Savinov, Y. Maeda, H. Kichimi, M. Welsch, Concettina Sfienti, T. M. G. Kraetzschmar, E. Prencipe, M. Yonenaga, T. Bilka, G. Varner, W. Gradl, Ya-Qiu Jin, R. de Sangro, C. Niebuhr, R. Stroili, T. K. Pedlar, Y. Seino, S. Ogawa, B. G. Cheon, Z. J. Liptak, N. Rad, M. Watanabe, E. Torassa, H. Ozaki, Paul Jackson, Yang Li, M. Wakai, C. Hadjivasiliou, L. M. Cremaldi, L. K. Li, Q. D. Zhou, A. Sangal, A. Rostomyan, J. Wiechczynski, I. Ripp-Baudot, V. Popov, E. Waheed, M. V. Purohit, N. Dash, E. Solovieva, M. Hohmann, A. Selce, T. Kuhr, S. Sandilya, U. Tamponi, E. Paoloni, S. Cunliffe, C.-L. Hsu, Seongbae Yang, C. La Licata, R. Itoh, B. G. Fulsom, A. Hershenhorn, K. Cho, Seema Bahinipati, A. Fodor, S. Bilokin, M. C. Chang, Antonio Budano, D. A. Sanders, G. Dujany, S. Patra, Q. Y. Liu, C. Miller, Y. Sakai, H. G. Moser, M. Z. Wang, K. Kinoshita, A. Panta, Nils Braun, Y-J Kwon, M. Merola, T. Geßler, Pavel Krokovny, D. Dossett, O. Hartbrich, S. Lacaprara, Leo Piilonen, K. Trabelsi, A. Paladino, M. Starič, S. K. Choi, Enrico Bernieri, P. Lewis, S. C. Lee, P. Taras, S. Uno, A. Passeri, I. Komarov, Peter Kodys, W. W. Jacobs, H. Tanigawa, S. Pardi, T. Koga, Kodai Matsuoka, Sw. Banerjee, F. Forti, G. B. Mohanty, Alberto Aloisio, Y. Yusa, A. De Yta-Hernandez, M. Hernandez Villanueva, Y. Kato, D. Ferlewicz, Doo Young Kim, I. Adachi, G. Polat, G. Casarosa, M. Mrvar, M. Bertemes, T. Uglov, M. E. Sevior, I. S. Lee, P. Goldenzweig, S. Fiore, Victoria Zhukova, M. H. A. Nouxman, L. Lanceri, W. Sutcliffe, R. Cheaib, Frank Simon, Yi Fan Hu, A. Vinokurova, R. Manfredi, I. Heredia-De La Cruz, G. Inguglia, N. Anh Ky, P. Branchini, C. H. Wang, E. Graziani, C. Hearty, G. Karyan, P. Gomis, J. F. Strube, D. Červenkov, Sunil Bansal, K. Senyo, D. Biswas, Rakesh Kumar, K. Miyabayashi, D. J. Summers, A. B. Kaliyar, S. Spataro, R. J. Sobie, John Webb, X. P. Xu, L. Vitale, E. Won, Takuya Higuchi, V. Aushev, M. T. Prim, S. Baehr, H. J. Kim, Stefano Longo, Dipak Kumar Sahoo, P. Bambade, Andreas Warburton, F. Meier, Bruce Yabsley, M. Remnev, K. Azmi, F. Abudinén, B. Golob, N. K. Nisar, J. S. Lange, T. D. Kimmel, S. Stefkova, D. Cinabro, R. Giordano, Jürgen Becker, P. Chang, M. Kumar, B. Paschen, Kohei Ogawa, F. Di Capua, A. Natochii, K. Inami, K. Unger, S. Bettarini, J. Libby, I. Nakamura, J. M. Roney, F. Ameli, M. Sumihama, C. Praz, R. Godang, Prafulla Kumar Behera, J. Irakkathil Jabbar, H. E. Cho, and Pere Rados

Subjects
Physics, Range (particle radiation), Particle physics, Gauge boson, Luminosity (scattering theory), Photon, 010308 nuclear & particles physics, General Physics and Astronomy, 01 natural sciences, law.invention, Standard Model, Pseudoscalar, Direct production, law, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Collider
Abstract

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e+e-→γa, a→γγ in the mass range 0.2

Published
2020

25. Transverse Single-Spin Asymmetry for Very Forward Neutral Pion Production in Polarized p+p Collisions at s=510 GeV

Author

Takashi Sako, Yoshitaka Itow, Jongmin Lee, M. H. Kim, T. Ljubicic, N. Sakurai, R. Seidl, O. Adriani, K. Sato, Y. Makino, Eugenio Berti, Hiroaki Menjo, Raffaello D'Alessandro, I. Nakagawa, A. Ogawa, K. Tanida, Shoji Torii, Y. Goto, Lorenzo Bonechi, Q. D. Zhou, M. Ueno, K. Kasahara, J. S. Park, Alessia Tricomi, and Byung-Sik Hong

Subjects
Physics, media_common.quotation_subject, General Physics and Astronomy, Asymmetry, Momentum, Nuclear physics, Transverse plane, Pion, Pseudorapidity, High Energy Physics::Experiment, Nuclear Experiment, Relativistic Heavy Ion Collider, STAR detector, media_common, Spin-½
Abstract

Transverse single-spin asymmetries of very forward neutral pions generated in polarized p+p collisions allow us to understand the production mechanism in terms of perturbative and nonperturbative strong interactions. During 2017, the RHICf Collaboration installed an electromagnetic calorimeter in the zero-degree region of the STAR detector at the Relativistic Heavy Ion Collider (RHIC) and measured neutral pions produced at pseudorapidity larger than 6 in polarized p+p collisions at sqrt[s]=510 GeV. The large nonzero asymmetries increasing both in longitudinal momentum fraction x_{F} and transverse momentum p_{T} have been observed at low transverse momentum p_{T}

Published
2020

26. Search for an Invisibly Decaying Z′ Boson at Belle II in e+e−→μ+μ−(e±μ∓) Plus Missing Energy Final States

Author

I. Ripp-Baudot, F. Meggendorfer, V.N. Zhilich, D. Ferlewicz, E. Nakano, G.V. Russo, N. Akopov, S. Nishida, S. Longo, H. M. Wakeling, A. Pathak, M. De Nuccio, Rocky Bala Garg, L. Cao, Nataliia Kovalchuk, B. Spruck, T. J. Moon, T. Iijima, Soumen Paul, Dipak Kumar Sahoo, C. Kleinwort, K. Kumara, S. Fiore, W. B. Yan, Bumho Kim, C. W. Joo, K. Chilikin, Takeo Higuchi, Felix Metzner, Z. S. Stottler, P. Sartori, G. De Pietro, K. Miyabayashi, L. Zani, C. Wessel, N. K. Nisar, M. Bessner, C. Miller, C. Niebuhr, V. Babu, Abner Soffer, B. Scavino, E. Graziani, E. De La Cruz-Burelo, Elisa Manoni, Yang Chen, S. Reiter, R. Peschke, S. Sandilya, H. Windel, Carlos Marinas, M. Wakai, Marco Milesi, J. Baudot, C. Hadjivasiliou, Yoshinobu Unno, C. Hearty, T. Kuhr, H. G. Moser, I. Komarov, M. Bertemes, M. Nishimura, T. V. Dong, N. Taniguchi, J. H. Yin, U. Tamponi, Antonio Budano, Iki Adachi, Doo Young Kim, Agnese Martini, T. Ferber, A. K. Giri, Z. P. Zhang, V. Gaur, L. B. Rizzuto, T. Sumiyoshi, K. K. Joo, R. Godang, J. C. Mei, B. Paschen, S. Bussino, T. K. Pedlar, Soohyun Cho, S. Kurz, Tariq Aziz, Kohei Ogawa, K. Dort, S. Marcello, L. Corona, Prafulla Kumar Behera, Leo Piilonen, P. Taras, K. Azmi, Martin Ritter, Dmytro Levit, M. Masuda, B. Golob, L. Santelj, J. Gemmler, G. Casarosa, S. Wehle, M. Hernandez Villanueva, K. Inami, A. Vossen, G. Dujany, E. C. Hill, V. Aushev, J. S. Lange, A. Paladino, T. Czank, F. Dattola, T. D. Kimmel, S. Dey, D. Biswas, K. Nishimura, Frank Simon, S. E. Vahsen, A. B. Kaliyar, C. Rosenfeld, R. M. Seddon, A. Hershenhorn, A. Fodor, M. Remnev, A. Sangal, Vladimir Popov, J. Schueler, H. Park, A. Bozek, Kiyoshi Tanida, Sw. Banerjee, Felix Mueller, L. K. Li, M. Merola, S. Jia, Y. Iwasaki, Y. Sakai, E. Paoloni, L. Burmistrov, Pavel Krokovny, D. Dossett, P. K. Resmi, C.-L. Hsu, Y. J. Kwon, G. Finocchiaro, A. Panta, K. Lieret, S. Lacaprara, I. Domínguez Jiménez, R. Cheaib, Tagir Aushev, Seongbae Yang, J. Irakkathil Jabbar, Q. Y. Liu, S. Cunliffe, Makoto Tabata, Jakub Kandra, Andreas Warburton, Jürgen Becker, S. Yamada, E. Prencipe, Z. Doležal, N. Rout, V. Zhukova, Y. Onuki, Xiaopeng Zhou, A. De Yta-Hernandez, D. Červenkov, G. B. Mohanty, Alberto Aloisio, Y. Kato, G. Varner, J. F. Strube, M. C. Chang, M. Z. Wang, Peter Kodys, W. W. Jacobs, B. G. Fulsom, Y. Yusa, M. Nayak, B. Oberhof, T. Koga, A. Passeri, C. P. Shen, Y. Kim, P. Branchini, J. Bennett, M. Takizawa, T. Matsuda, K. Senyo, Enrico Bernieri, G. Karyan, L. Lanceri, S. K. Choi, S. Baehr, P. Gomis, Yi Fan Hu, Florian Urs Bernlochner, F. Di Capua, Shuji Tanaka, H. Aihara, E. Solovieva, G. Muroyama, S. Duell, I. M. Peruzzi, P. Oskin, M. Maggiora, Kevin Varvell, H. Atmacan, S. Y. Suzuki, K. Lautenbach, Pere Rados, G. Rizzo, M. Bračko, G. Pakhlova, Y.-T. Chen, M. Destefanis, M. Piccolo, W. Gradl, Y. Onishchuk, Y. Jin, C. H. Wang, D. Greenwald, A. Vinokurova, J. G. Shiu, S. Dubey, I. Heredia-De La Cruz, D. E. Jaffe, S. Bettarini, F. Müller, S. Spataro, O. Hartbrich, H. Ozaki, K. Cho, H. Miyake, K. Trabelsi, S. H. Kim, Y. Guan, K. Unger, P. Pakhlov, M. Eliachevitch, Rakesh Kumar, A. Kuzmin, V. Savinov, T. M. G. Kraetzschmar, F. Bianchi, C. Z. Yuan, M. Campajola, F. Tenchini, Th. Müller, A. Sibidanov, Yukinori Sato, E. Won, R. A. Briere, S. H. Robertson, R. Pestotnik, Kodai Matsuoka, M. Hoek, E. J. Jang, R. Rasheed, V. Chekelian, D. Rodríguez Pérez, K. Kim, H. Hayashii, H. Ono, R. Van Tonder, H. Ye, M. Barrett, R. Mizuk, L. Li Gioi, Y. B. Li, C. H. Kim, G. De Nardo, M. T. Hedges, Yongsun Kim, B. Gobbo, P. Leitl, Hidekazu Kakuno, Concettina Sfienti, S. Uno, R. Stroili, B. G. Cheon, C. Schwanda, L. M. Cremaldi, D. Cinabro, E. Torassa, Claudia Cecchi, M. V. Purohit, S. Korpar, S. C. Lee, T. Hara, F. Forti, T. Geßler, M. Garcia-Hernandez, E. Ganiev, S. Halder, J. M. Roney, M. Yonenaga, M. Sumihama, M. Watanabe, T. E. Browder, H. Kindo, C. Praz, P. Bambade, J. Libby, D. M. Asner, K. Hayasaka, M. T. Prim, Takeo Kawasaki, Andrey Sokolov, A. Gaz, James E. Fast, Semen Eidelman, J. Kahn, F. Meier, R. Mussa, H. B. Jeon, Bruce Yabsley, S. Stefkova, R. Giordano, G. Inguglia, A. Ishikawa, G. Nazaryan, Y. Seino, M. Kumar, M. Nakao, Somnath Choudhury, P. Križan, S. Kohani, Y. Ushiroda, M. Uchida, Tao Luo, A. Gellrich, Y. Maeda, T. Tsuboyama, D. Matvienko, Q. D. Zhou, J. Wiechczynski, C. La Licata, B.A. Shwartz, M. Starič, D. Liventsev, T. Morii, R. Kroeger, I. S. Lee, P. Goldenzweig, N. Anh Ky, R. de Sangro, Z. Liptak, P. Ahlburg, W. A. T. Wan Abdullah, D. J. Summers, R. Itoh, A. Rostomyan, R. J. Sobie, John Webb, L. Vitale, J. Kumar, D. Neverov, A. Selce, and Vikas Bansal

Subjects
Physics, Coupling constant, Particle physics, Missing energy, Physics beyond the Standard Model, General Physics and Astronomy, 01 natural sciences, law.invention, law, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Collider, Boson
Abstract

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z′. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z′ in the process e+e-→μ+μ-Z′ and of a lepton-flavor-violating Z′ in e+e-→e±μZ′. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an Lμ-Lτ theory, into upper limits on the Z′ coupling constant at the level of 5×10-2-1 for MZ′≤6 GeV/c2.

Published
2020

27. Search for an Invisibly Decaying Z′ Boson at Belle II in e+e- →μ+μ- (e±μ) Plus Missing Energy Final States

Author

I, Adachi, P, Ahlburg, H, Aihara, N, Akopov, A, Aloisio, N, Anh Ky, D M, Asner, H, Atmacan, T, Aushev, V, Aushev, T, Aziz, V, Babu, S, Baehr, P, Bambade, Sw, Banerjee, V, Bansal, M, Barrett, J, Baudot, J, Becker, P K, Behera, J V, Bennett, E, Bernieri, F U, Bernlochner, M, Bertemes, M, Bessner, S, Bettarini, F, Bianchi, D, Biswas, A, Bozek, M, Bračko, P, Branchini, R A, Briere, T E, Browder, A, Budano, L, Burmistrov, S, Bussino, M, Campajola, L, Cao, G, Casarosa, C, Cecchi, D, Červenkov, M-C, Chang, R, Cheaib, V, Chekelian, Y Q, Chen, Y-T, Chen, B G, Cheon, K, Chilikin, K, Cho, S, Cho, S-K, Choi, S, Choudhury, D, Cinabro, L, Corona, L M, Cremaldi, S, Cunliffe, T, Czank, F, Dattola, E, De La Cruz-Burelo, G, De Nardo, M, De Nuccio, G, De Pietro, R, de Sangro, M, Destefanis, S, Dey, A, De Yta-Hernandez, F, Di Capua, Z, Doležal, I, Domínguez Jiménez, T V, Dong, K, Dort, D, Dossett, S, Dubey, S, Duell, G, Dujany, S, Eidelman, M, Eliachevitch, J E, Fast, T, Ferber, D, Ferlewicz, G, Finocchiaro, S, Fiore, A, Fodor, F, Forti, B G, Fulsom, E, Ganiev, M, Garcia-Hernandez, R, Garg, V, Gaur, A, Gaz, A, Gellrich, J, Gemmler, T, Geßler, R, Giordano, A, Giri, B, Gobbo, R, Godang, P, Goldenzweig, B, Golob, P, Gomis, W, Gradl, E, Graziani, D, Greenwald, Y, Guan, C, Hadjivasiliou, S, Halder, T, Hara, O, Hartbrich, K, Hayasaka, H, Hayashii, C, Hearty, M T, Hedges, I, Heredia de la Cruz, M, Hernández Villanueva, A, Hershenhorn, T, Higuchi, E C, Hill, M, Hoek, C-L, Hsu, Y, Hu, T, Iijima, K, Inami, G, Inguglia, J, Irakkathil Jabbar, A, Ishikawa, R, Itoh, Y, Iwasaki, W W, Jacobs, D E, Jaffe, E-J, Jang, H B, Jeon, S, Jia, Y, Jin, C, Joo, K K, Joo, J, Kahn, H, Kakuno, A B, Kaliyar, J, Kandra, G, Karyan, Y, Kato, T, Kawasaki, B H, Kim, C-H, Kim, D Y, Kim, K-H, Kim, S-H, Kim, Y K, Kim, Y, Kim, T D, Kimmel, H, Kindo, C, Kleinwort, P, Kodyš, T, Koga, S, Kohani, I, Komarov, S, Korpar, N, Kovalchuk, T M G, Kraetzschmar, P, Križan, R, Kroeger, P, Krokovny, T, Kuhr, J, Kumar, M, Kumar, R, Kumar, K, Kumara, S, Kurz, A, Kuzmin, Y-J, Kwon, S, Lacaprara, C, La Licata, L, Lanceri, J S, Lange, K, Lautenbach, I-S, Lee, S C, Lee, P, Leitl, D, Levit, L K, Li, Y B, Li, J, Libby, K, Lieret, L, Li Gioi, Z, Liptak, Q Y, Liu, D, Liventsev, S, Longo, T, Luo, Y, Maeda, M, Maggiora, E, Manoni, S, Marcello, C, Marinas, A, Martini, M, Masuda, T, Matsuda, K, Matsuoka, D, Matvienko, F, Meggendorfer, J C, Mei, F, Meier, M, Merola, F, Metzner, M, Milesi, C, Miller, K, Miyabayashi, H, Miyake, R, Mizuk, K, Azmi, G B, Mohanty, T, Moon, T, Morii, H-G, Moser, F, Mueller, F J, Müller, Th, Muller, G, Muroyama, R, Mussa, E, Nakano, M, Nakao, M, Nayak, G, Nazaryan, D, Neverov, C, Niebuhr, N K, Nisar, S, Nishida, K, Nishimura, M, Nishimura, B, Oberhof, K, Ogawa, Y, Onishchuk, H, Ono, Y, Onuki, P, Oskin, H, Ozaki, P, Pakhlov, G, Pakhlova, A, Paladino, A, Panta, E, Paoloni, H, Park, B, Paschen, A, Passeri, A, Pathak, S, Paul, T K, Pedlar, I, Peruzzi, R, Peschke, R, Pestotnik, M, Piccolo, L E, Piilonen, V, Popov, C, Praz, E, Prencipe, M T, Prim, M V, Purohit, P, Rados, R, Rasheed, S, Reiter, M, Remnev, P K, Resmi, I, Ripp-Baudot, M, Ritter, G, Rizzo, L B, Rizzuto, S H, Robertson, D, Rodríguez Pérez, J M, Roney, C, Rosenfeld, A, Rostomyan, N, Rout, G, Russo, D, Sahoo, Y, Sakai, S, Sandilya, A, Sangal, L, Santelj, P, Sartori, Y, Sato, V, Savinov, B, Scavino, J, Schueler, C, Schwanda, R M, Seddon, Y, Seino, A, Selce, K, Senyo, C, Sfienti, C P, Shen, J-G, Shiu, B, Shwartz, A, Sibidanov, F, Simon, R J, Sobie, A, Soffer, A, Sokolov, E, Solovieva, S, Spataro, B, Spruck, M, Starič, S, Stefkova, Z S, Stottler, R, Stroili, J, Strube, M, Sumihama, T, Sumiyoshi, D J, Summers, S Y, Suzuki, M, Tabata, M, Takizawa, U, Tamponi, S, Tanaka, K, Tanida, N, Taniguchi, P, Taras, F, Tenchini, E, Torassa, K, Trabelsi, T, Tsuboyama, M, Uchida, K, Unger, Y, Unno, S, Uno, Y, Ushiroda, S E, Vahsen, R, van Tonder, G S, Varner, K E, Varvell, A, Vinokurova, L, Vitale, A, Vossen, M, Wakai, H M, Wakeling, W, Wan Abdullah, C H, Wang, M-Z, Wang, A, Warburton, M, Watanabe, J, Webb, S, Wehle, C, Wessel, J, Wiechczynski, H, Windel, E, Won, B, Yabsley, S, Yamada, W, Yan, S B, Yang, H, Ye, J H, Yin, M, Yonenaga, C Z, Yuan, Y, Yusa, L, Zani, Z, Zhang, V, Zhilich, Q D, Zhou, X Y, Zhou, V I, Zhukova, Adachi, I., Ahlburg, P., Aihara, H., Akopov, N., Aloisio, A., Anh Ky, N., Asner, D. M., Atmacan, H., Aushev, T., Aushev, V., Aziz, T., Babu, V., Baehr, S., Bambade, P., Banerjee, Sw., Bansal, V., Barrett, M., Baudot, J., Becker, J., Behera, P. K., Bennett, J. V., Bernieri, E., Bernlochner, F. U., Bertemes, M., Bessner, M., Bettarini, S., Bianchi, F., Biswas, D., Bozek, A., Bračko, M., Branchini, P., Briere, R. A., Browder, T. E., Budano, A., Burmistrov, L., Bussino, S., Campajola, M., Cao, L., Casarosa, G., Cecchi, C., Červenkov, D., Chang, M. -C., Cheaib, R., Chekelian, V., Chen, Y. Q., Chen, Y. -T., Cheon, B. G., Chilikin, K., Cho, K., Cho, S., Choi, S. -K., Choudhury, S., Cinabro, D., Corona, L., Cremaldi, L. M., Cunliffe, S., Czank, T., Dattola, F., De La Cruz-Burelo, E., De Nardo, G., De Nuccio, M., De Pietro, G., de Sangro, R., Destefanis, M., Dey, S., De Yta-Hernandez, A., Di Capua, F., Doležal, Z., Domínguez Jiménez, I., Dong, T. V., Dort, K., Dossett, D., Dubey, S., Duell, S., Dujany, G., Eidelman, S., Eliachevitch, M., Fast, J. E., Ferber, T., Ferlewicz, D., Finocchiaro, G., Fiore, S., Fodor, A., Forti, F., Fulsom, B. G., Ganiev, E., Garcia-Hernandez, M., Garg, R., Gaur, V., Gaz, A., Gellrich, A., Gemmler, J., Geßler, T., Giordano, R., Giri, A., Gobbo, B., Godang, R., Goldenzweig, P., Golob, B., Gomis, P., Gradl, W., Graziani, E., Greenwald, D., Guan, Y., Hadjivasiliou, C., Halder, S., Hara, T., Hartbrich, O., Hayasaka, K., Hayashii, H., Hearty, C., Hedges, M. T., Heredia de la Cruz, I., Hernández Villanueva, M., Hershenhorn, A., Higuchi, T., Hill, E. C., Hoek, M., Hsu, C. -L., Hu, Y., Iijima, T., Inami, K., Inguglia, G., Irakkathil Jabbar, J., Ishikawa, A., Itoh, R., Iwasaki, Y., Jacobs, W. W., Jaffe, D. E., Jang, E. -J., Jeon, H. B., Jia, S., Jin, Y., Joo, C., Joo, K. K., Kahn, J., Kakuno, H., Kaliyar, A. B., Kandra, J., Karyan, G., Kato, Y., Kawasaki, T., Kim, B. H., Kim, C. -H., Kim, D. Y., Kim, K. -H., Kim, S. -H., Kim, Y. K., Kim, Y., Kimmel, T. D., Kindo, H., Kleinwort, C., Kodyš, P., Koga, T., Kohani, S., Komarov, I., Korpar, S., Kovalchuk, N., Kraetzschmar, T. M. G., Križan, P., Kroeger, R., Krokovny, P., Kuhr, T., Kumar, J., Kumar, M., Kumar, R., Kumara, K., Kurz, S., Kuzmin, A., Kwon, Y. -J., Lacaprara, S., La Licata, C., Lanceri, L., Lange, J. S., Lautenbach, K., Lee, I. -S., Lee, S. C., Leitl, P., Levit, D., Li, L. K., Li, Y. B., Libby, J., Lieret, K., Li Gioi, L., Liptak, Z., Liu, Q. Y., Liventsev, D., Longo, S., Luo, T., Maeda, Y., Maggiora, M., Manoni, E., Marcello, S., Marinas, C., Martini, A., Masuda, M., Matsuda, T., Matsuoka, K., Matvienko, D., Meggendorfer, F., Mei, J. C., Meier, F., Merola, M., Metzner, F., Milesi, M., Miller, C., Miyabayashi, K., Miyake, H., Mizuk, R., Azmi, K., Mohanty, G. B., Moon, T., Morii, T., Moser, H. -G., Mueller, F., Müller, F. J., Muller, Th., Muroyama, G., Mussa, R., Nakano, E., Nakao, M., Nayak, M., Nazaryan, G., Neverov, D., Niebuhr, C., Nisar, N. K., Nishida, S., Nishimura, K., Nishimura, M., Oberhof, B., Ogawa, K., Onishchuk, Y., Ono, H., Onuki, Y., Oskin, P., Ozaki, H., Pakhlov, P., Pakhlova, G., Paladino, A., Panta, A., Paoloni, E., Park, H., Paschen, B., Passeri, A., Pathak, A., Paul, S., Pedlar, T. K., Peruzzi, I., Peschke, R., Pestotnik, R., Piccolo, M., Piilonen, L. E., Popov, V., Praz, C., Prencipe, E., Prim, M. T., Purohit, M. V., Rados, P., Rasheed, R., Reiter, S., Remnev, M., Resmi, P. K., Ripp-Baudot, I., Ritter, M., Rizzo, G., Rizzuto, L. B., Robertson, S. H., Rodríguez Pérez, D., Roney, J. M., Rosenfeld, C., Rostomyan, A., Rout, N., Russo, G., Sahoo, D., Sakai, Y., Sandilya, S., Sangal, A., Santelj, L., Sartori, P., Sato, Y., Savinov, V., Scavino, B., Schueler, J., Schwanda, C., Seddon, R. M., Seino, Y., Selce, A., Senyo, K., Sfienti, C., Shen, C. P., Shiu, J. -G., Shwartz, B., Sibidanov, A., Simon, F., Sobie, R. J., Soffer, A., Sokolov, A., Solovieva, E., Spataro, S., Spruck, B., Starič, M., Stefkova, S., Stottler, Z. S., Stroili, R., Strube, J., Sumihama, M., Sumiyoshi, T., Summers, D. J., Suzuki, S. Y., Tabata, M., Takizawa, M., Tamponi, U., Tanaka, S., Tanida, K., Taniguchi, N., Taras, P., Tenchini, F., Torassa, E., Trabelsi, K., Tsuboyama, T., Uchida, M., Unger, K., Unno, Y., Uno, S., Ushiroda, Y., Vahsen, S. E., van Tonder, R., Varner, G. S., Varvell, K. E., Vinokurova, A., Vitale, L., Vossen, A., Wakai, M., Wakeling, H. M., Wan Abdullah, W., Wang, C. H., Wang, M. -Z., Warburton, A., Watanabe, M., Webb, J., Wehle, S., Wessel, C., Wiechczynski, J., Windel, H., Won, E., Yabsley, B., Yamada, S., Yan, W., Yang, S. B., Ye, H., Yin, J. H., Yonenaga, M., Yuan, C. Z., Yusa, Y., Zani, L., Zhang, Z., Zhilich, V., Zhou, Q. D., Zhou, X. Y., and Zhukova, V. I.

Subjects
High Energy Physics::Experiment
Abstract

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z^{'}. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z^{'} in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'} and of a lepton-flavor-violating Z^{'} in e^{+}e^{-}→e^{±}μ^{∓}Z^{'}. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an L_{μ}-L_{τ} theory, into upper limits on the Z^{'} coupling constant at the level of 5×10^{-2}-1 for M_{Z^{'}}≤6 GeV/c^{2}.

Published
2020

28. Commissioning and Operation of the Upgraded Belle II DAQ System with PCI-Express-Based High-Speed Readout

Author

Y.-T. Lai, M. Bessner, D. Biswas, D. Charlet, T. S. Lau, D. Levit, O. Hartbrich, T. Higuchi, R. Itoh, E. Jules, P. Kapusta, T. Kunigo, M. Nakao, K. Nishimura, S. Park, E. Plaige, H. Purwar, P. Robbe, R. Sugiura, S.Y. Suzuki, M. Taurigna, G. Varner, S. Yamada, and Q.-D. Zhou

Subjects
Nuclear and High Energy Physics, Nuclear Energy and Engineering, Electrical and Electronic Engineering
Published
2022

29. Measurement of forward photon production cross-section in proton–proton collisions at s=13TeV with the LHCf detector

Author

T. K. Sako, Hiroaki Menjo, Yoshitaka Itow, Alessia Tricomi, Toshiharu Suzuki, A. Tiberio, E. Matsubayashi, M. Haguenauer, N. Sakurai, O. Adriani, Y. Makino, T. Tamura, M. Ueno, K. Kasahara, W. C. Turner, Kimiaki Masuda, Raffaello D'Alessandro, S. B. Ricciarini, Eugenio Berti, M. Bongi, P. Papini, Lorenzo Bonechi, T. Iwata, Yasushi Muraki, Maiko Shinoda, Shoji Torii, and Q. D. Zhou

Subjects
Physics, Nuclear and High Energy Physics, Photon, Large Hadron Collider, Proton, 010308 nuclear & particles physics, Hadron, Cosmic ray, Interaction model, 7. Clean energy, 01 natural sciences, Nuclear physics, Pseudorapidity, 0103 physical sciences, Ultra-high-energy cosmic ray, Nuclear Experiment, 010306 general physics
Abstract

In this paper, we report the production cross-section of forward photons in the pseudorapidity regions of η>10.94 and 8.99>η>8.81 , measured by the LHCf experiment with proton–proton collisions at s=13TeV . The results from the analysis of 0.191nb−1 of data obtained in June 2015 are compared to the predictions of several hadronic interaction models that are used in air-shower simulations for ultra-high-energy cosmic rays. Although none of the models agree perfectly with the data, EPOS-LHC shows the best agreement with the experimental data among the models.

Published
2018

30. Precise Measurement of the D⁰ and D⁺ Lifetimes at Belle II

Author

F., Abudinén, I., Adachi, K., Adamczyk, L., Aggarwal, H., Ahmed, H., Aihara, N., Akopov, A., Aloisio, N., Anh Ky, D. M., Asner, H., Atmacan, V., Aushev, V., Babu, S., Bacher, H., Bae, S., Baehr, S., Bahinipati, P., Bambade, Sw., Banerjee, S., Bansal, M., Barrett, J., Baudot, M., Bauer, A., Baur, J., Becker, P. K., Behera, J. V., Bennett, E., Bernieri, F. U., Bernlochner, M., Bertemes, E., Bertholet, M., Bessner, S., Bettarini, V., Bhardwaj, F., Bianchi, T., Bilka, S., Bilokin, D., Biswas, A., Bobrov, D., Bodrov, A., Bolz, A., Bozek, M., Bračko, P., Branchini, N., Braun, R. A., Briere, T. E., Browder, A., Budano, S., Bussino, M., Campajola, L., Cao, G., Casarosa, C., Cecchi, D., Červenkov, M.-C., Chang, P., Chang, R., Cheaib, V., Chekelian, C., Chen, Y.-T., Chen, B. G., Cheon, K., Chilikin, K., Chirapatpimol, H.-E., Cho, K., Cho, S.-J., Cho, S.-K., Choi, S., Choudhury, D., Cinabro, L., Corona, L. M., Cremaldi, S., Cunliffe, T., Czank, F., Dattola, E., De La Cruz-Burelo, G., de Marino, G., De Nardo, G., De Pietro, R., de Sangro, M., Destefanis, S., Dey, A., De Yta-Hernandez, A., Di Canto, F., Di Capua, J., Dingfelder, Z., Doležal, I., Domínguez Jiménez, T. V., Dong, M., Dorigo, K., Dort, D., Dossett, S., Dubey, S., Duell, G., Dujany, P., Ecker, D., Epifanov, T., Ferber, D., Ferlewicz, G., Finocchiaro, K., Flood, A., Fodor, F., Forti, B. G., Fulsom, A., Gabrielli, N., Gabyshev, A., Gaz, A., Gellrich, G., Giakoustidis, R., Giordano, A., Giri, A., Glazov, B., Gobbo, R., Godang, P., Goldenzweig, B., Golob, W., Gradl, E., Graziani, D., Greenwald, T., Gu, Y., Guan, K., Gudkova, J., Guilliams, C., Hadjivasiliou, S., Halder, K., Hara, T., Hara, O., Hartbrich, K., Hayasaka, H., Hayashii, S., Hazra, C., Hearty, I., Heredia de la Cruz, M., Hernández Villanueva, A., Hershenhorn, T., Higuchi, E. C., Hill, H., Hirata, M., Hoek, M., Hohmann, C.-L., Hsu, T., Humair, T., Iijima, K., Inami, G., Inguglia, A., Ishikawa, R., Itoh, M., Iwasaki, Y., Iwasaki, W. W., Jacobs, D. E., Jaffe, E.-J., Jang, S., Jia, Y., Jin, H., Junkerkalefeld, H., Kakuno, A. B., Kaliyar, J., Kandra, K. H., Kang, R., Karl, G., Karyan, Y., Kato, T., Kawasaki, C., Kiesling, C.-H., Kim, D. Y., Kim, Y.-K., Kim, Y., Kim, T. D., Kimmel, K., Kinoshita, P., Kodyš, T., Koga, S., Kohani, T., Konno, S., Korpar, E., Kovalenko, R., Kowalewski, T. M. G., Kraetzschmar, F., Krinner, P., Križan, P., Krokovny, T., Kuhr, J., Kumar, M., Kumar, R., Kumar, K., Kumara, S., Kurz, A., Kuzmin, Y.-J., Kwon, S., Lacaprara, K., Lalwani, T., Lam, L., Lanceri, J. S., Lange, M., Laurenza, K., Lautenbach, F. R., Le Diberder, S. C., Lee, P., Leitl, D., Levit, C., Li, L. K., Li, J., Libby, K., Lieret, Z., Liptak, Q. Y., Liu, D., Liventsev, S., Longo, T., Lueck, C., Lyu, R., Manfredi, E., Manoni, C., Marinas, A., Martini, T., Matsuda, K., Matsuoka, D., Matvienko, J. A., McKenna, F., Meier, M., Merola, F., Metzner, C., Miller, K., Miyabayashi, R., Mizuk, G. B., Mohanty, N., Molina-Gonzalez, H., Moon, H.-G., Moser, M., Mrvar, C., Murphy, R., Mussa, I., Nakamura, K. R., Nakamura, M., Nakao, H., Nakazawa, Z., Natkaniec, A., Natochii, G., Nazaryan, C., Niebuhr, M., Niiyama, N. K., Nisar, S., Nishida, K., Nishimura, S., Ogawa, Y., Onishchuk, H., Ono, Y., Onuki, P., Oskin, E. R., Oxford, H., Ozaki, P., Pakhlov, A., Paladino, T., Pang, A., Panta, E., Paoloni, S., Pardi, H., Park, S.-H., Park, B., Paschen, A., Passeri, A., Pathak, S., Patra, S., Paul, T. K., Pedlar, I., Peruzzi, R., Peschke, R., Pestotnik, F., Pham, M., Piccolo, L. E., Piilonen, G., Pinna Angioni, P. L. M., Podesta-Lerma, T., Podobnik, S., Pokharel, G., Polat, V., Popov, C., Praz, S., Prell, E., Prencipe, M. T., Prim, M. V., Purohit, H., Purwar, N., Rad, P., Rados, S., Raiz, S., Reiter, M., Remnev, I., Ripp-Baudot, G., Rizzo, L. B., Rizzuto, S. H., Robertson, J. M., Roney, A., Rostomyan, N., Rout, M., Rozanska, D., Sahoo, D. A., Sanders, S., Sandilya, A., Sangal, L., Santelj, Y., Sato, V., Savinov, B., Scavino, J., Schueler, C., Schwanda, A. J., Schwartz, Y., Seino, A., Selce, K., Senyo, J., Serrano, C., Sfienti, J.-G., Shiu, B., Shwartz, A., Sibidanov, F., Simon, R. J., Sobie, A., Soffer, A., Sokolov, E., Solovieva, S., Spataro, B., Spruck, M., Starič, S., Stefkova, Z. S., Stottler, R., Stroili, J., Strube, M., Sumihama, W., Sutcliffe, S. Y., Suzuki, H., Svidras, M., Tabata, M., Takizawa, U., Tamponi, S., Tanaka, K., Tanida, H., Tanigawa, N., Taniguchi, F., Tenchini, R., Tiwary, D., Tonelli, E., Torassa, N., Toutounji, K., Trabelsi, T., Tsuboyama, I., Ueda, S., Uehara, Y., Uematsu, T., Uglov, K., Unger, Y., Unno, K., Uno, S., Uno, P., Urquijo, Y., Ushiroda, Y. V., Usov, S. E., Vahsen, R., van Tonder, G. S., Varner, A., Vinokurova, L., Vitale, A., Vossen, E., Waheed, H. M., Wakeling, E., Wang, M.-Z., Wang, X. L., Wang, A., Warburton, M., Watanabe, M., Welsch, C., Wessel, J., Wiechczynski, E., Won, X. P., Xu, B. D., Yabsley, S., Yamada, W., Yan, S. B., Yang, H., Ye, J., Yelton, J. H., Yin, K., Yoshihara, Y., Yusa, L., Zani, V., Zhilich, Q. D., Zhou, X. Y., Zhou, V. I., Zhukova, and R., Žlebčík

Abstract

We report a measurement of the D⁰ and D⁺ lifetimes using D⁰→K⁻π⁺ and D⁺→K⁻π⁺π⁺ decays reconstructed in e⁺e⁻→[Formula: see text] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e⁺e⁻ collider. The data, collected at center-of-mass energies at or near the Υ(4S) resonance, correspond to an integrated luminosity of 72 fb⁻¹. The results, τ(D⁰)=410.5±1.1(stat)±0.8(syst) fs and τ(D⁺)=1030.4±4.7(stat)±3.1(syst) fs, are the most precise to date and are consistent with previous determinations.

Published
2021

31. An upgrade solution for Belle II DAQ system

Author

Zhen'An Liu, R. Itoh, Wenxuan Gong, Hanjun Kou, Jingzhou Zhao, Jia Tao, Jianing Song, Q. D. Zhou, Satoru Yamada, and Pengcheng Cao

Subjects
business.product_category, 010308 nuclear & particles physics, business.industry, Firmware, Computer science, computer.software_genre, 01 natural sciences, Data acquisition, Upgrade, Advanced Mezzanine Card, 0103 physical sciences, Scalability, Bandwidth (computing), Network switch, Electronics, 010306 general physics, business, computer, Computer hardware
Abstract

The Belle II experiment has just started data acquisition in May 2018 which pushes the upgrade of the DAQ system into action. The Present system is based on the Belle2link system which collects the digitized data in each of the Front End electronics of detector systems and moves them to the COPPER( Common readout Platform) readout. Data from COPPER system will be sent to readout PC via network switch for data packing and processing. To meet the further requirement in the future higher luminosity SuperKEKB running, a discussion for a DAQ upgrade is underway to keep the Belle2link functionalities but replace the COPPER readout by new technology. This talk presents a solution for this upgrade based on a MicroTCA compatible CPPF+ module developed for CMS trigger phase I upgrade. In this solution the FEE part of Belle2link will be kept so that there is no need to change the FEE electronics hardware and firmware at all for all functionalities including the slow control.The back-end part of Belle2link implemented in the HSLB(High Speed receiver Link Board) daughter card of COPPER board will be reimplemented in the CPPF+ board, which provides powerful data concentration and processing, providing output capabilities of up to 10Gbps network bandwidth. The slow control will be done via another PC which is connected to MCH shelf manager. The advantage of this solution is that the transition from present to the upgrade system is smooth as we can share most of the Belle2link back-end firmware in HSLB, and the xTCA platform provides much higher scalability, re-configurability, and reliabilities.

Published
2019

32. The Performance of Belle II Data Acquisition System in the First Physics Run

Author

S-H Park, Satoru Yamada, Q. D. Zhou, Jingzhou Zhao, Tomoyuki Konno, Z. A. Liu, R. Itoh, N. Braun, Y. Guan, M. Nakao, S. Y. Suzuki, B. Spruck, S. Reiter, C. Li, K. Lautenbach, and Oskar Hartbrich

Subjects
Physics, business.product_category, Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, business.industry, media_common.quotation_subject, Detector, 01 natural sciences, Sample (graphics), Front and back ends, Data acquisition, Debugging, 0103 physical sciences, Computer data storage, Network switch, 010306 general physics, business, Computer hardware, Data reduction, media_common
Abstract

The Belle II experiment is a new generation B-factory experiment at KEK in Japan aiming at the search for New Physics in a huge sample of B-meson dacays. The commissioning of the SuperKEKB accelerator was started in 2017 (Phase 1), and then a pilot run with outer detectors was performed in 2018 (Phase 2). From March this year, an operation with the full detector has been started for the physics data taking (Phase 3). The Belle II data acquisiton system (DAQ) is now fully working in the Phase 3 run. The system consists of the trigger timing distribution system, the common readout modules (COPPER) with the unified optical data link to the detector front end, the readout PCs and the network switch complext for the event building, and the modularized high level trigger (HLT) and storage system. The system features the real time feedback of the track information obtained by HLT to the readout system of the pixel detector for the data reduction. The particle tracks reconstructed using the silicon vertex detector (SVD) and the central drift chamber (CDC) signals are extrapolated to the surface of the pixel detector (PXD) by the real time HLT processing, and only the hits in the sensors associated with the tracks are merged with the data from other detectors after the HLT processing (the 2nd level event building).The first physics data taking has been performed in Phase 3 run for 4 months. The typical level 1 rate is up to 3.5 kHz and the data taking efficiency is more than 90 % when the accelerator operation is stable. The HLT processing is fully implemented and the event reduction rate is about 1/8. However, various troubles occured in both the detector readout and in the HLT operation. The debugging and improvement are now in progress to stabilize the system for the autumn run.

Published
2019

33. The Performance of Belle II High Level Trigger in the First Physics Run

Author

Tomoyuki Konno, B. Spruck, S. Yamada, S-H Park, Jingzhou Zhao, Z. A. Liu, K. Lautenbach, Oskar Hartbrich, R. Itoh, Nils Braun, S. Y. Suzuki, Yinghui Guan, Chunhua Li, M. Nakao, Q. D. Zhou, and S. Reiter

Subjects
Physics, High level trigger, 010308 nuclear & particles physics, business.industry, QC1-999, Detector, Real-time computing, 01 natural sciences, Sample (graphics), Set (abstract data type), Data acquisition, Software, Data quality, 0103 physical sciences, Real-time data, 010306 general physics, business
Abstract

The Belle II experiment is a new generation B-factory experiment at KEK in Japan aiming at the search for New Physics in a huge sample of B-meson decays. The commissioning of the accelerator and the detector for the first physics run has started from March this year. The Belle II High Level Trigger (HLT) is fully working in the beam run. The HLT is now operated with 1600 cores clusterized in 5 units, which is 1/4 of the full configuration. The software trigger is performed using the same offline reconstruction code, and events are classified into a set of physics categories. Only the events in the categories of interest are finally sent out to the storage. Live data quality monitoring is also performed on HLT. For the selected events, the reconstructed tracks are extrapolated to the surface of the pixel detector (PXD) and quickly fed back to the readout electronics for the real time data reduction by sending only the associated hits. The maximum trigger rate in the first physics run was 3.5kHz, and the Belle II data acquisition system was stably operated. There were several problems in the HLT operation, but they have successfully been fixed during the data taking period. The HLT reduction factor is measured to be 8 which is still higher than the design because of the high background environment.

Published
2020

34. Measurement of inclusive forward neutron production cross section in proton-proton collisions at $$ \sqrt{s}=13 $$ TeV with the LHCf Arm2 detector

Author

Toshiharu Suzuki, Raffaello D'Alessandro, Y. Makino, Katsuaki Kasahara, M. Bongi, Yasushi Muraki, W. C. Turner, Kimiaki Masuda, M. Haguenauer, Alessia Tricomi, N. Sakurai, Masato Shinoda, Yoshitaka Itow, E. Berti, Q. D. Zhou, O. Adriani, Shoji Torii, A. Tiberio, Kenta Sato, Hiroaki Menjo, T. Tamura, Ken Ohashi, L. Bonechi, Takashi Sako, S. B. Ricciarini, P. Papini, S. Detti, M. Ueno, École polytechnique (X), and LHCf

Subjects
p p: scattering, Nuclear and High Energy Physics, Particle physics, interaction: model, Proton, 13000 GeV-cms, air, FOS: Physical sciences, Unfolding, 01 natural sciences, energy dependence, rapidity dependence, High Energy Physics - Experiment, differential cross section: measured, High Energy Physics - Experiment (hep-ex), Cross section (physics), Hadron-Hadron scattering (experiments), 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Neutron, structure, cosmic radiation: UHE, Nuclear Experiment, 010306 general physics, Physics, Range (particle radiation), rapidity: difference, Large Hadron Collider, showers: atmosphere, hep-ex, 010308 nuclear & particles physics, LHC-F, Forward physics, Hadron-Hadron scattering (experiments), Unfolding, CERN LHC Coll, Pseudorapidity, Forward physics, High Energy Physics::Experiment, Production (computer science), n: production, numerical calculations: Monte Carlo, p p: colliding beams, Particle Physics - Experiment, Energy (signal processing), experimental results
Abstract

In this paper, we report the measurement relative to the production of forward neutrons in proton-proton collisions at $ \sqrt{s}=13 $ TeV obtained using the LHCf Arm2 detector at the Large Hadron Collider. The results for the inclusive differential production cross section are presented as a function of energy in three different pseudorapidity regions: η > 10.76, 8.99 < η < 9.22 and 8.81 < η < 8.99. The analysis was performed using a data set acquired in June 2015 that corresponds to an integrated luminosity of 0.194 nb$^{−1}$. The measurements were compared with the predictions of several hadronic interaction models used to simulate air showers generated by Ultra High Energy Cosmic Rays. None of these generators showed good agreement with the data for all pseudorapidity intervals. For η > 10.76, no model is able to reproduce the observed peak structure at around 5 TeV and all models underestimate the total production cross section: among them, QGSJET II-04 shows the smallest deficit with respect to data for the whole energy range. For 8.99 < η < 9.22 and 8.81 < η < 8.99, the models having the best overall agreement with data are SIBYLL 2.3 and EPOS-LHC, respectively: in particular, in both regions SIBYLL 2.3 is able to reproduce the observed peak structure at around 1.5–2.5 TeV. In this paper, we report the measurement relative to the production of forward neutrons in proton-proton collisions at $\mathrm{\sqrt{s} = 13~TeV}$ obtained using the LHCf Arm2 detector at the Large Hadron Collider. The results for the inclusive differential production cross section are presented as a function of energy in three different pseudorapidity regions: $\eta > 10.76$, $8.99 < \eta < 9.22$ and $8.81 < \eta < 8.99$. The analysis was performed using a data set acquired in June 2015 that corresponds to an integrated luminosity of $\mathrm{0.194~nb^{-1}}$. The measurements were compared with the predictions of several hadronic interaction models used to simulate air showers generated by Ultra High Energy Cosmic Rays. None of these generators showed good agreement with the data for all pseudorapidity intervals. For $\eta > 10.76$, no model is able to reproduce the observed peak structure at around $\mathrm{5~TeV}$ and all models underestimate the total production cross section: among them, QGSJET II-04 shows the smallest deficit with respect to data for the whole energy range. For $8.99 < \eta < 9.22$ and $8.81 < \eta < 8.99$, the models having the best overall agreement with data are SIBYLL 2.3 and EPOS-LHC, respectively: in particular, in both regions SIBYLL 2.3 is able to reproduce the observed peak structure at around $\mathrm{1.5-2.5~TeV}$.

Published
2018

35. The Resent Results from the LHCf Experiment

Author

N. Sakurai, Hiroaki Menjo, Takashi Sako, S. B. Ricciarini, M. Ueno, P. Papini, Yutaka Matsubara, Shoji Torii, Maurice Haguenauer, E. Matsubayashi, Y. Makino, Alessia Tricomi, Taishi Iwata, Raffaello D'Alessandro, Alessio Tiberio, Kenta Sato, Q. D. Zhou, Yoshitaka Itow, Massimo Bongi, Eugenio Berti, Y. Shimizu, Katsuaki Kasahara, T. Tamura, Kenji Yoshida, Yasushi Muraki, Maiko Shinoda, Lorenzo Bonechi, Bill Turner, Kimiaki Masuda, Takuya Suzuki, O. Adriani, G. Castellini, and École polytechnique (X)

Subjects
Astrophysics and Astronomy, p p: scattering, Photon, air, Astrophysics::High Energy Astrophysical Phenomena, energy spectrum, Cosmic ray, Hadronic interaction models, 01 natural sciences, 7. Clean energy, spectrum, Nuclear physics, 0103 physical sciences, Energy spectrum, Nuclear Experiment, 010306 general physics, Neutral particle, hadron hadron: interaction, Physics, UHECRs, showers: atmosphere, 010308 nuclear & particles physics, photon, LHC-F, neutral particle, CERN LHC Coll, cosmic radiation, LHC, numerical calculations: Monte Carlo, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; The LHCf experiment is an LHC experiment dedicated to measure the production spectra of forward neutral particles, photons, \(\pi ^{0}\)s and neutrons. The obtained results are very useful to test hadronic interaction models which are used in MC simulations for cosmic-ray air shower developments. The LHCf had an operation in 2015 with p–p collisions at \(\sqrt{s} \) = 13 TeV, which corresponds to the collision energy of 0.9 × 10^17 eV in the laboratory frame. We discuss the results of the inclusive energy spectra for forward photons obtained at p–p, \(\sqrt{s} \) = 13 TeV data as well as \(\pi ^{0}\) results taken at p–p, \(\sqrt{s} \) = 7 TeV. In addition we introduce future prospects of LHCf analyses and activities.

Published
2018

36. Monte Carlo study of diffraction in proton-proton collisions at $\sqrt{s}$=13TeV with the very forward detector

Author

Hiroaki Menjo, Q. D. Zhou, Yoshitaka Itow, and Takashi Sako

Subjects
Diffraction, Nuclear physics, Physics, Proton, 010308 nuclear & particles physics, 0103 physical sciences, Detector, Hadron, Monte Carlo method, Physics::Optics, High Energy Physics::Experiment, 010303 astronomy & astrophysics, 01 natural sciences
Abstract

Diffractive and non-diffractive collisions are totally different hadronic interaction processes, the diffractive processes are hardly predicted theoretically. This leads to the significant differences in the treatments of diffraction in the hadronic interaction models. Very forward detectors at colliders have unique sensitivity to diffractive processes, and they can be a powerful tool for studying diffractive dissociation by combining them with central detectors. Central information enables classification of the forward productions into diffraction and nondiffraction categories; in particular, most of the surviving events from the selection of diffraction belong to low-mass diffraction events which have not been measured precisely.

Published
2017

37. Performance study for the photon measurements of the upgraded LHCf calorimeters with Gd$_2$SiO$_5$ (GSO) scintillators

Author

Hiroaki Menjo, Yoshitaka Itow, Katsuaki Kasahara, Alessio Tiberio, T. Iwata, W. C. Turner, Takashi Sako, S. B. Ricciarini, Massimo Bongi, P. Papini, Eugenio Berti, Kimiaki Masuda, E. Matsubayashi, Yasushi Muraki, O. Adriani, Alessia Tricomi, Y. Makino, Shoji Torii, N. Sakurai, S. Detti, M. Haguenauer, Q. D. Zhou, M. Ueno, Z. Caccia, G. Mitsuka, Toshiharu Suzuki, Lorenzo Bonechi, T. Tamura, Raffaello D'Alessandro, M. Del Prete, and École polytechnique (X)

Subjects
Particle physics, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, energy resolution, Cosmic ray, Scintillator, 01 natural sciences, 7. Clean energy, Particle detector, Nuclear physics, Calorimeters, Hodoscope, Particle tracking detectors, 0103 physical sciences, calorimeter, electron: irradiation, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, Nuclear Experiment, Instrumentation, spatial resolution, Mathematical Physics, scintillation counter, Physics, CalibrationCosmic ray detectorsCosmic raysCosmologyIntelligent systemsIonizationMonte Carlo methodsPhotonsScintillation countersTellurium compounds, Large Hadron Collider, 010308 nuclear & particles physics, hodoscope, LHC-F, energy: calibration, Calorimeter, Air shower, muon: irradiation, Scintillation counter, High Energy Physics::Experiment, silicon: oxygen, photon: detector, gadolinium, numerical calculations: Monte Carlo, performance
Abstract

The Large Hadron Collider forward (LHCf) experiment was motivated to understand the hadronic interaction processes relevant to cosmic-ray air shower development. We have developed radiation-hard detectors with the use of Gd2SiO5 (GSO) scintillators for proton-proton ?s = 13 TeV collisions. Calibration of such detectors for photon measurement has been completed at the CERN SPS T2-H4 line in 2015 using electron beams of 100-250 GeV and muon beams of 150-250 GeV . After the channel-by-channel absolute energy calibration, the energy resolution of the calorimeters is confirmed to be better than 3% for electrons with energy above 100 GeV . The position dependence of the energy scale of the calorimeters was reduced to the level of 1% after the corrections for scintillator nonuniformity and the shower leakage effect. The position resolution of the new shower imaging detector, a GSO-bar hodoscope interleaved in the calorimeter, was 100 ?m for 200 GeV electrons. The experimental results are well explained by Monte Carlo simulations. We have confirmed that the new detectors meet the requirement of the LHCf experiment at ?s = 13 TeV. © 2017 IOP Publishing Ltd and Sissa Medialab srl.

Published
2017

38. Transverse single spin asymmetry for very forward π0 production in polarized proton-proton collisions at √s = 510 GeV

Author

M. H. Kim, Hiroaki Menjo, R. Seidl, Emanuele Berti, Kenta Sato, O. Adriani, Takashi Sako, M. Ueno, K. Kasahara, I. Nakagawa, Y. Goto, J. S. Park, Alessia Tricomi, N. Sakurai, Lorenzo Bonechi, Byung-Sik Hong, Kiyoshi Tanida, Q. D. Zhou, Toshiharu Suzuki, Raffaello D'Alessandro, Shoji Torii, and Yoshitaka Itow

Subjects
Physics, Range (particle radiation), Proton, QC1-999, media_common.quotation_subject, High Energy Physics::Phenomenology, Asymmetry, Nuclear physics, Transverse plane, Pseudorapidity, Transverse momentum, High Energy Physics::Experiment, Nuclear Experiment, Spin-½, media_common
Abstract

Transverse single spin asymmetry, AN, of very forward π0 production from polarized p + p collisions provides new information toward an understanding of its production mechanism. AN of forward π0 in the pseudorapidity region of 3 < η < 4 has been described by the partonic structure of the proton in the perturbative QCD framework. However, recent data indicates a potential contribution from not only partonic but also diffractive interactions. In order to provide a new insight on the origin of the AN, we measured the very forward π0 production in the pseudorapidity region of 6 < η from √s = 510 GeV polarized p + p collisions at RHIC in 2017. We report our measurement of the very forward π0 over the transverse momentum range of 0 < pT < 1 GeV/c and the preliminary result.

Published
2019

39. Recent results from the LHCf and RHICf experiments

Author

W. C. Turner, Kenta Sato, Kimiaki Masuda, Kiyoshi Tanida, Hiroaki Menjo, Lorenzo Bonechi, Shoji Torii, I. Nakagawa, O. Adriani, Q. D. Zhou, M. H. Kim, R. Seidl, N. Sakurai, M. Bongi, Raffaello D'Alessandro, A. Tiberio, Byung-Sik Hong, M. Ueno, K. Kasahara, Toshiharu Suzuki, Y. Goto, M. Haguenauer, J. S. Park, Alessia Tricomi, T. Tamura, Yasushi Muraki, Ken Ohashi, Eugenio Berti, Yoshitaka Itow, Takashi Sako, S. B. Ricciarini, P. Papini, École polytechnique (X), LHCf, and RHICf

Subjects
Astrophysics and Astronomy, heavy ion: scattering, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Cosmic ray, 01 natural sciences, 7. Clean energy, talk: Nagoya 2018/05/21, Nuclear physics, 0103 physical sciences, calorimeter, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Rapidity, Nuclear Experiment, 010306 general physics, neutral particle: particle identification, Brookhaven RHIC Coll, Physics, Large Hadron Collider, showers: atmosphere, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, LHC-F, Calorimeter, rapidity, forward production, CERN LHC Coll, Air shower, cosmic radiation, High Energy Physics::Experiment, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Relativistic Heavy Ion Collider, performance, Particle Physics - Experiment, experimental results
Abstract

The Large Hadron Collider forward and the Relativistic Heavy Ion Collider forward experiments measured forward particles produced in high-energy hadron collisions at the LHC and RHIC. Using compact calorimeters neutral particles produced in pseudorapidities η >8.4 and η >6.0 are observed by the respective experiments. Because the collision energies ranging from 0.51 TeV to 13 TeV correspond to the cosmic-ray equivalent energies of 1014 to 1017 eV, the measurements are important to understand the hadronic interaction relevant to extensive air shower measurements. This paper reviews recent results of LHCf and initial performance of RHICf that took data in the 2017 RHIC operation.

Published
2019

40. Measurements of longitudinal and transverse momentum distributions for neutral pions in the forward-rapidity region with the LHCf detector

Author

N. Sakurai, W. C. Turner, Kimiaki Masuda, E. Matsubayashi, Katsuaki Kasahara, Y. Makino, Takahiro Iwata, Lorenzo Bonechi, M. Haguenauer, O. Adriani, M. Ueno, A. Tiberio, M. Del Prete, Hiroaki Menjo, M. Bongi, Toshiharu Suzuki, Yasushi Muraki, A. L. Perrot, Eugenio Berti, T. Tamura, Takashi Sako, G. Mitsuka, Shoji Torii, S. B. Ricciarini, P. Papini, Q. D. Zhou, Kiyoshi Kawade, Alessia Tricomi, Raffaello D'Alessandro, and Yoshitaka Itow

Subjects
Particle physics, Physics and Astronomy (miscellaneous), Nuclear Theory, Hadron, FOS: Physical sciences, Cosmic ray, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), symbols.namesake, Pion, 0103 physical sciences, Feynman diagram, Rapidity, Nuclear Experiment, 010306 general physics, Physics, Large Hadron Collider, 010308 nuclear & particles physics, Detector, Transverse plane, symbols, Physics::Accelerator Physics, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract

The differential cross sections for inclusive neutral pions as a function of transverse and longitudinal momentum in the very forward rapidity region have been measured at the Large Hadron Collider (LHC) with the Large Hadron Collider forward detector (LHCf) in proton-proton collisions at $\sqrt{s}=$ 2.76 and 7 TeV and in proton-lead collisions at nucleon-nucleon center-of-mass energies of $\sqrt{s_\text{NN}}=$ 5.02 TeV. Such differential cross sections in proton-proton collisions are compatible with the hypotheses of limiting fragmentation and Feynman scaling. Comparing proton-proton with proton-lead collisions, we find a sizable suppression of the production of neutral pions in the differential cross sections after subtraction of ultra-peripheral proton-lead collisions. This suppression corresponds to the nuclear modification factor value of about 0.1-0.3. The experimental measurements presented in this paper provide a benchmark for the hadronic interaction Monte Carlo simulation codes that are used for the simulation of cosmic ray air showers., Comment: 47 pages, 23 figures, 59 tables, accepted in PRD

Published
2016

41. The performance for the TeV photon measurement of the LHCf upgraded detector using Gd 2 SiO 5 (GSO) scintillators

Author

Shoji Torii, M. Ueno, Katsuaki Kasahara, M. Bongi, Hiroaki Menjo, Q. D. Zhou, W. C. Turner, E. Matsubayashi, Kimiaki Masuda, Raffaello D'Alessandro, Y. Makino, M. Haguenauer, T. Iwata, Yoshitaka Itow, Yasushi Muraki, Eugenio Berti, G. Castellini, O. Adriani, Takashi Sako, S. B. Ricciarini, P. Papini, Alessia Tricomi, Lorenzo Bonechi, T. Tamura, A. Tiberio, T. Suzuki, and École polytechnique (X)

Subjects
Particle physics, Nuclear and High Energy Physics, Photon, Physics::Instrumentation and Detectors, Instrumentation, energy resolution, Scintillator, 7. Clean energy, 01 natural sciences, Calorimeters, Colliding beam accelerators, Ionization, Tellurium compounds Air shower experiments, Electro-magnetic showers, Hadronic interaction models, Integrated luminosity, Irradiation conditions, Large Hadron Collider, Sampling calorimeters, UHECRs, Nuclear physics, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, Nuclear Experiment, Image resolution, spatial resolution, Sampling calorimeter, GSO, Physics, Luminosity (scattering theory), irradiation, 010308 nuclear & particles physics, Scintillating detector, Detector, mass resolution, LHC-F, stability, calibration, GSO, Sampling calorimeter, Scintillating detector, UHECRs, Nuclear and High Energy Physics, Instrumentation, Air shower, scintillation counter: crystal, High Energy Physics::Experiment, silicon: oxygen, calorimeter: upgrade, gadolinium, performance
Abstract

International audience; The Large Hadron Collider forward (LHCf) experiment measures the forward particle production at the LHC to verify hadronic interaction models used in air shower experiments. We have upgraded very small sampling and imaging calorimeters using GSO scintillators to measure the most energetic particles generated in s =13 TeV p–p collisions at the zero-degree region of the LHC. Upgraded detectors were calibrated at the SPS North area facility in CERN and it was confirmed that the detector can measure electro-magnetic showers with energy resolution of 3% and position resolution of better than 123 μm for 100 GeV electrons. The operation of LHCf in 13 TeV p–p collisions has been successfully completed with integrated luminosity of 5 nb −1 . Reconstructed π 0 peak with the mass resolution of 3.7% and stability less than 1% during the operation implies that our measurement was stable enough in the high irradiation condition.

Published
2016

42. LHCf experiment: Forward physics at LHC for cosmic rays study

Author

O. Adriani, T. Tamura, Lorenzo Bonechi, Alessia Tricomi, E. Matsubayashi, Y. Makino, Alessio Tiberio, Shoji Torii, Raffaello D'Alessandro, M. Haguenauer, G. Mitsuka, Takashi Sako, S. B. Ricciarini, P. Papini, Q. D. Zhou, M. Bongi, Eugenio Berti, Toshiharu Suzuki, G. Castellini, Y. Okuno, M. Del Prete, N. Sakurai, W. C. Turner, Kimiaki Masuda, Hiroaki Menjo, Y. Sugiura, Kiyoshi Kawade, Yasushi Muraki, Katsuaki Kasahara, A. L. Perrot, and Yoshitaka Itow

Subjects
Physics, Astrophysics and Astronomy, Future perspective, Particle properties, Large Hadron Collider, 010308 nuclear & particles physics, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Nuclear Theory, Cosmic ray, Astrophysics, 01 natural sciences, Nuclear physics, Physics and Astronomy (all), neutron, cosmic rays, 0103 physical sciences, Physics::Accelerator Physics, Ultra-high-energy cosmic ray, 010306 general physics, Nuclear Experiment, Energy (signal processing), Particle Physics - Experiment
Abstract

The LHCf experiment, optimized for the study of forward physics at LHC, completes its main physics program in this year 2015, with the proton-proton collisions at the energy of 13 TeV. LHCf gives important results on the study of neutral particles at extreme pseudo-rapidity, both for proton-proton and for proton-ion interactions. These results are an important reference for tuning the models of the hadronic interaction currently used for the simulation of the atmospheric showers induced by very high energy cosmic rays. The results of this analysis and the future perspective are presented in this paper.

Published
2016

43. Latest LHCf results and preparation to the LHC run for 13 TeV proton–proton interactions

Author

Yasushi Muraki, Yoshitaka Itow, Toshiharu Suzuki, Kenji Yoshida, E. Matsubayashi, Y. Makino, W. C. Turner, Kimiaki Masuda, Hiroaki Menjo, T. Tamura, Raffaello D'Alessandro, Y. Sugiura, Alessia Tricomi, Massimo Bongi, G. Castellini, Eugenio Berti, G. Mitsuka, M. Del Prete, O. Adriani, M. Haguenauer, A. L. Perrot, Shoji Torii, Yasushi Shimizu, Katsuaki Kasahara, Yoshimi Matsubara, T. K. Sako, Q. D. Zhou, Y. Okuno, S. B. Ricciarini, N. Sakurai, P. Papini, Alessio Tiberio, and Lorenzo Bonechi

Subjects
Physics, COLLISIONS, Particle physics, PHOTON ENERGY-SPECTRA, Large Hadron Collider, Physics::Instrumentation and Detectors, QC1-999, Hadron, PHOTON ENERGY-SPECTRA, COLLISIONS, Nuclear physics, Upgrade, Physics::Accelerator Physics, High Energy Physics::Experiment, Neutral particle, Particle Physics - Experiment
Abstract

The LHCf experiment is a CERN experiment dedicated to forward physics which is optimized to measure the neutral particle flow at extreme pseudo-rapidity val- ues, ranging from 8.4 up to infinity. LHCf results are extremely important for the cal- ibration of the hadronic interaction models used for the study of the development of atmospheric showers in the Earth atmosphere. Starting from the recent run of proton- Lead nucleus interactions at LHC, the LHCf and ATLAS collaborations have performed a common data taking which allows a combined study of the central and forward re- gions of the interaction. The latest results of LHCf, the upgrade of the detectors for the next 6.5 TeV + 6.5 TeV proton-proton run and the status of the LHCf-ATLAS common activities are summarized in this paper.

Published
2015

44. Measurement of very forward neutron energy spectra for 7 TeV proton-proton collisions at the Large Hadron Collider

Author

Hiroaki Menjo, Yasushi Muraki, Shoji Torii, E. Matsubayashi, M. Bongi, Katsuaki Kasahara, Y. Makino, M. Haguenauer, Q. D. Zhou, Y. Sugiura, Takashi Sako, O. Adriani, S. B. Ricciarini, Alessia Tricomi, Eugenio Berti, Raffaello D'Alessandro, M. Del Prete, Lorenzo Bonechi, P. Papini, W. C. Turner, Yoshitaka Itow, G. Mitsuka, Kimiaki Masuda, Alessio Tiberio, Toshiharu Suzuki, T. Tamura, G. Castellini, Y. Okuno, N. Sakurai, Kentaro Kawade, and A. L. Perrot

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Range (particle radiation), Photon, Large Hadron Collider, Proton, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, lcsh:QC1-999, Neutron temperature, High Energy Physics - Experiment, Calorimeter, Hadronic-interaction model, Nuclear physics, Baryon, High Energy Physics - Experiment (hep-ex), Forward neutron production, Neutron, LHC, Nuclear Experiment (nucl-ex), Nuclear Experiment, lcsh:Physics, Particle Physics - Experiment
Abstract

The Large Hadron Collider forward (LHCf) experiment is designed to use the LHC to verify the hadronic-interaction models used in cosmic-ray physics. Forward baryon production is one of the crucial points to understand the development of cosmic-ray showers. We report the neutron-energy spectra for LHC $\sqrt{s}$ = 7 TeV proton--proton collisions with the pseudo-rapidity $\eta$ ranging from 8.81 to 8.99, from 8.99 to 9.22, and from 10.76 to infinity. The measured energy spectra obtained from the two independent calorimeters of Arm1 and Arm2 show the same characteristic feature before unfolding the difference in the detector responses. We unfolded the measured spectra by using the multidimensional unfolding method based on Bayesian theory, and the unfolded spectra were compared with current hadronic-interaction models. The QGSJET II-03 model predicts a high neutron production rate at the highest pseudo-rapidity range similar to our results and the DPMJET 3.04 model describes our results well at the lower pseudo-rapidity ranges. However no model perfectly explains the experimental results in the whole pseudo-rapidity range. The experimental data indicate the most abundant neutron production rate relative to the photon production, which does not agree with predictions of the models., Comment: 10pages, 6 figures

Published
2015

45. Recent Results from the LHCf Experiment

Author

Hiroaki Menjo, Dorothea Pfeiffer, Toshiharu Suzuki, G. Mitsuka, E. Matsubayashi, Y. Makino, Katsuaki Kasahara, A. L. Perrot, Y. Sugiura, M. Bongi, A. Tiberio, Y. Shimizu, Yoshitaka Itow, N. Sakurai, Raffaello D'Alessandro, Takashi Sako, S. B. Ricciarini, Q. D. Zhou, P. Papini, O. Adriani, M. Del Prete, Lorenzo Bonechi, Yasushi Muraki, Eugenio Berti, Shoji Torii, W. C. Turner, Kimiaki Masuda, T. Tamura, M. Haguenauer, G. Castellini, Kiyoshi Kawade, Alessia Tricomi, and École polytechnique (X)

Subjects
Photon, interaction: model, Physics::Instrumentation and Detectors, p nucleus: interaction, Hadron, Nuclear Theory, Astrophysics, 7. Clean energy, 01 natural sciences, Spectral line, transverse momentum: momentum spectrum, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], cosmic radiation: VHE, Nuclear Experiment, Physics, Large Hadron Collider, pi0: forward production, talk: Chiba 2014/03/19, UHECR, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, photon: energy spectrum: measured, 7000 GeV-cms, Particle Physics - Experiment, photon: forward production, p p: scattering, 5000 GeV-cms/nucleon, air, QC1-999, Astrophysics::High Energy Astrophysical Phenomena, Cosmic ray, Nuclear physics, Pion, 0103 physical sciences, Neutron, 010306 general physics, Neutral particle, lead, Interaction point, 010308 nuclear & particles physics, nuclear matter: effect, LHC-F, showers, hadronic interaction, Air shower, n: transverse momentum, Physics::Accelerator Physics, High Energy Physics::Experiment, LHCf, pi0: transverse momentum, experimental results
Abstract

The LHC-forward (LHCf) experiment, situated at the LHC accelerator, has measured neutral particles production in a very forward region (pseudo-rapidity > 8.4) in proton-proton and proton-lead collisions. The main purpose of the LHCf experiment is to test hadronic interaction models used in cosmic rays experiments to imulate cosmic rays induced air-showers in Earth’s atmosphere.The experiment is composed of two independent detectors located at 140m from the ATLAS interaction point (IP1) on opposite sides ; each detector is composed of two sampling calorimeters.Latest physics results from p-p and p-Pb collisions (at √s = 7 TeV and 5.02 TeV respectively) will be discussed in this paper ; in particular, the inclusive energy spectra of neutrons in p-p collisions and the transverse momentum spectra of neutral pions for different pseudo-rapidity ranges in p-Pb collisions will be shown.

Published
2014

46. A detailed study on Gd2SiO5scintillators: recovery from increased photon yield following irradiation

Author

Hiroaki Menjo, T. K. Sako, Q. D. Zhou, Y. Sugiura, Kiyoshi Kawade, E. Matsubayashi, Y. Makino, and Kimiaki Masuda

Subjects
Physics, Physics::Instrumentation and Detectors, business.industry, Infrared, Analytical chemistry, Gamma ray, Scintillator, Photon yield, Intensity (physics), Light intensity, Optics, Irradiation, business, Instrumentation, Mathematical Physics, Excitation
Abstract

Increased light intensity and recovery of GSO scintillators following irradiation were studied by using accelerator beams of 290 MeV/n carbon nuclei. This is the first measurement of recovery phase by using accelerator beams. The obtained results were consistent with previous results obtained by using 60Co gamma rays and UV excitation. We confirmed a 23% increase in light intensity following irradiation with 7.4 kGy as well as exponential recovery on a time scale of 104s. The temporal profile of recovery was fitted by a single exponential with an asymptotic increase of 13±1% relative to the light intensity before irradiation. Active recovery was attempted by exposing an irradiated GSO sample to infrared light with intensity up to 8.3 kW/cm2, but no indication of accelerated recovery was observed.

Published
2015

47. Trend of pesticide poisoning in recent decades in China

Author

D S, Xue, Y, Li, Z G, Jin, B G, Tao, and Q D, Zhou

Subjects
Adult, Male, Occupational Diseases, China, Adolescent, Acute Disease, Humans, Female, Longitudinal Studies, Middle Aged, Pesticides
Abstract

The past decade experienced a stunning change in the incidence and fatality rates of pesticide poisonings in China. A study on representative case records of pesticide poisoning in a chinese province is presented here. A three-fold increase in poisoning cases due to a lack of preventive measures was reported at the beginning of the 1980s, under the rural economic reformation. Occupational intoxication incidence was swiftly reduced within a couple of years, and further stepped down as the adequate means were taken. On the contrary, the increase in non-occupational cases declined very slowly. The fatality rate of occupational poisoning cases was kept low (around few per thousand), while the non-occupational remarkably declined from 30% to 11% thanks to the efforts of health and medical care centres. The number and fatality rate of non-occupational cases thus came to play a more and more important role. Such trend is worth our attention.

Published
1999

48. Lubricated sliding and rolling wear of austempered ductile iron

Author

Q.-D. Zhou, W.-S. Zhou, and S.-K. Meng

Subjects
Materials science, Mechanics of Materials, Mechanical Engineering, Modeling and Simulation, Metallurgy, General Materials Science, Austempering, Industrial and Manufacturing Engineering
Published
1994

49. Solidification Behaviour of Boron-Bearing High-chromium Cast Iron and the Modification Mechanism of Silicon

Author

J. Shen and Q. D. Zhou

Subjects
Bearing (mechanical), Materials science, Silicon, Metallurgy, chemistry.chemical_element, General Medicine, engineering.material, law.invention, Chromium, chemistry, law, engineering, Cast iron, Boron
Abstract

The solidification of high-chromium cast iron containing 2.5% C, 0.3% Mn, 15% Cr, 0.7% Mo, 0.5% B and various concentrations of Si is examined. Samples were liquid quenched at different stages of t...

Published
1988

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