Measurements of the Branching Fractions of the Semileptonic Decays Ξc0→Ξ−ℓ+νℓ and the Asymmetry Parameter of Ξc0→Ξ−π+

Autor: S. Jia, U. Tamponi, Dipak Kumar Sahoo, S. Pardi, A. Garmash, M. Bessner, G. Bonvicini, A. Natochii, N. K. Nisar, A. Vinokurova, M. Iwasaki, O. Hartbrich, B. Bhuyan, J. S. Lange, K. Uno, Andrey Sokolov, P. Krokovny, O. Grzymkowska, C. H. Wang, K.-H. Kim, L. E. Piilonen, Rakesh Kumar, J. Bennett, Jyoti Prakash Biswal, B. G. Cheon, D. Liventsev, K. H. Kang, K. Cho, S. Paul, S. Al Said, D. Cinabro, M. Z. Wang, K. Kinoshita, Yizeng Li, Semen Eidelman, Y. Jin, R. Kroeger, I. S. Lee, V. Savinov, M. Uchida, R. Mussa, T. Pang, A. Ishikawa, S. Patra, M. Kumar, P. Križan, P. Goldenzweig, H. Ye, R. Mizuk, S. Nishida, H. Ono, V. Bhardwaj, K. Adamczyk, S. Korpar, D. Epifanov, G.V. Russo, S. Das, Y. Iwasaki, A. Kuzmin, L. Nayak, V. Babu, G. Schnell, Y. J. Kwon, X. P. Xu, X. L. Wang, Prafulla Kumar Behera, S. Ogawa, G. S. Varner, J. T. McNeil, L. Li Gioi, A. Korobov, C. W. Joo, E. Prencipe, Somnath Choudhury, R. Van Tonder, N. Rout, M. Sumihama, P. L. Wang, T. Ferber, T. K. Pedlar, T. Kuhr, S. Cunliffe, H. Hayashii, R. Ayad, K. Kumara, M. Niiyama, R. Itoh, R. Dhamija, A. Rostomyan, J. G. Shiu, J. Libby, D. M. Asner, L. K. Li, M. C. Chang, K. Hayasaka, A. K. Giri, T. Mori, H. Aihara, B. G. Fulsom, K. Tanida, D. Y. Kim, Y. Usov, Seongbae Yang, T. Bilka, Tagir Aushev, Z. S. Stottler, E. Kovalenko, V. Zhukova, Y. Onuki, K. Lalwani, C. H. Li, S. Uno, A. Vossen, M. Masuda, Iki Adachi, M. Watanabe, T. E. Browder, H. Park, A. Bozek, Tomoyuki Konno, K. Nishimura, Y. Seino, C. Schwanda, M. Hernandez Villanueva, M. Campajola, E. Won, S. Watanuki, T. Uglov, M. T. Prim, Z. P. Zhang, T. V. Dong, Y. Sakai, V.N. Zhilich, Y. Kato, S. Sandilya, K. Lieret, F. Tenchini, V. Gaur, S.-J. Cho, T. Podobnik, G. Pakhlova, C.-L. Hsu, M. Starič, N. Dash, E. Solovieva, C. Sharma, M. Nayak, K. Senyo, Peter Kodys, W. W. Jacobs, T. Sanuki, C. P. Shen, Seok Kim, Shih-Chang Lee, D. Matvienko, F. Di Capua, C. H. Kim, G. Karyan, H. Kichimi, P. Pakhlov, N. Gabyshev, D. Červenkov, Rocky Bala Garg, W. B. Yan, Sadaharu Uehara, C. Hadjivasiliou, J. H. Yin, M. Bračko, A. Chen, G. De Nardo, G. B. Mohanty, M. Shapkin, M. Röhrken, K. Chilikin, C. Z. Yuan, Y. Choi, V. Popov, L. Santelj, R. Pestotnik, S. K. Choi, K. Gudkova, Felix Metzner, K. K. Joo, T. J. Moon
Rok vydání: 2021
Předmět:
Zdroj: Physical Review Letters. 127
ISSN: 1079-7114
0031-9007
Popis: Using data samples of 89.5 and 711fb$^{-1}$ recorded at energies of $\sqrt{s}$=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e$^{+}$e$^{-}$ collider, we report measurements of branching fractions of semileptonic decays Ξ$_{c}$$^{0}$ → Ξ$^{-}$l$^{+}$ν$_{l}$(l=e or μ) and the CP-asymmetry parameter of Ξ$_{c}$$^{0}$ → Ξ$^{-}$π$^{+}$ decay. The branching fractions are measured to be B(Ξ$_{c}$$^{0}$ → Ξ$^{-}$e$^{+}$ν$_{e}$)= 1.31±0.04±0.07±0.38)% and B(Ξ$_{c}$$^{0}$ → Ξ$^{-}$μ$^{+}$ν$_{μ}$ = (1.27±0.06±0.10±0.37)% , and the decay parameter α$_{Ξπ}$ is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξ$_{c}$$^{0}$ → Ξ$^{-}$e$^{+}$ν$_{e}$) /B(Ξ$_{c}$$^{0}$ → Ξ$^{-}$μ$^{+}$ν$_{μ}$) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter A$_{CP}$=(α$_{Ξ^{-}π^{+}}$+α$_{Ξ^{+}π^{-}}$)/(α$_{Ξ^{-}π^{+}}$+α$_{Ξ^{+}π^{-}}$) = 0.024±0.052±0.014 is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the Ξ$_{c}$$^{0}$ → Ξ$^{-}$π$^{+}$ branching fraction.
Databáze: OpenAIRE