: The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.

Measurement of the Absolute Branching Fraction and Decay Asymmetry of Λ→nγ

Bianchi, F;Bortone, A;Destefanis, M;De Mori, F;Greco, M;Lavezzi, L;Maggiora, M;Marcello, S;Sosio, S;Spataro, S;
2022-01-01

Abstract

: The radiative hyperon decay Λ→nγ is studied using (10087±44)×10^{6}  J/ψ events collected with the BESIII detector operating at BEPCII. The absolute branching fraction of the decay Λ→nγ is determined to be (0.832±0.038_{stat}±0.054_{syst})×10^{-3}, which is a factor of 2.1 lower and 5.6 standard deviations different than the previous measurement. By analyzing the joint angular distribution of the decay products, the first determination of the decay asymmetry α_{γ} is reported with a value of -0.16±0.10_{stat}±0.05_{syst}.
2022
129
21
212002-1
212002-8
Ablikim, M; Achasov, M N; Adlarson, P; Albrecht, M; Aliberti, R; Amoroso, A; An, M R; An, Q; Bai, X H; Bai, Y; Bakina, O; Baldini Ferroli, R; Balossino, I; Ban, Y; Batozskaya, V; Becker, D; Begzsuren, K; Berger, N; Bertani, M; Bettoni, D; Bianchi, F; Bloms, J; Bortone, A; Boyko, I; Briere, R A; Brueggemann, A; Cai, H; Cai, X; Calcaterra, A; Cao, G F; Cao, N; Cetin, S A; Chang, J F; Chang, W L; Chelkov, G; Chen, C; Chen, Chao; Chen, G; Chen, H S; Chen, M L; Chen, S J; Chen, S M; Chen, T; Chen, X R; Chen, X T; Chen, Y B; Chen, Z J; Cheng, W S; Choi, S K; Chu, X; Cibinetto, G; Cossio, F; Cui, J J; Dai, H L; Dai, J P; Dbeyssi, A; de Boer, R E; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, J; Dong, L Y; Dong, M Y; Dong, X; Du, S X; Egorov, P; Fan, Y L; Fang, J; Fang, S S; Fang, W X; Fang, Y; Farinelli, R; Fava, L; Feldbauer, F; Felici, G; Feng, C Q; Feng, J H; Fischer, K; Fritsch, M; Fritzsch, C; Fu, C D; Gao, H; Gao, Y N; Gao, Yang; Garbolino, S; Garzia, I; Ge, P T; Ge, Z W; Geng, C; Gersabeck, E M; Gilman, A; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, L M; Gu, M H; Gu, Y T; Guan, C Y; Guo, A Q; Guo, L B; Guo, R P; Guo, Y P; Guskov, A; Han, T T; Han, W Y; Hao, X Q; Harris, F A; He, K K; He, K L; Heinsius, F H; Heinz, C H; Heng, Y K; Herold, C; Himmelreich, M; Hou, G Y; Hou, Y R; Hou, Z L; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, K X; Huang, L Q; Huang, L Q; Huang, X T; Huang, Y P; Huang, Z; Hussain, T; Hüsken, N; Imoehl, W; Irshad, M; Jackson, J; Jaeger, S; Janchiv, S; Jang, E; Jeong, J H; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Ji, Y Y; Jia, Z K; Jiang, H B; Jiang, S S; Jiang, X S; Jiang, Y; Jiao, J B; Jiao, Z; Jin, S; Jin, Y; Jing, M Q; Johansson, T; Kalantar-Nayestanaki, N; Kang, X S; Kappert, R; Kavatsyuk, M; Ke, B C; Keshk, I K; Khoukaz, A; Kiese, P; Kiuchi, R; Kliemt, R; Koch, L; Kolcu, O B; Kopf, B; Kuemmel, M; Kuessner, M; Kupsc, A; Kühn, W; Lane, J J; Lange, J S; Larin, P; Lavania, A; Lavezzi, L; Lei, Z H; Leithoff, H; Lellmann, M; Lenz, T; Li, C; Li, C; Li, C H; Li, Cheng; Li, D M; Li, F; Li, G; Li, H; Li, H; Li, H B; Li, H J; Li, H N; Li, J Q; Li, J S; Li, J W; Li, Ke; Li, L J; Li, L K; Li, Lei; Li, M H; Li, P R; Li, S X; Li, S Y; Li, T; Li, W D; Li, W G; Li, X H; Li, X L; Li, Xiaoyu; Liang, H; Liang, H; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Liao, L Z; Libby, J; Limphirat, A; Lin, C X; Lin, D X; Lin, T; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, G M; Liu, H; Liu, H B; Liu, H M; Liu, Huanhuan; Liu, Huihui; Liu, J B; Liu, J L; Liu, J Y; Liu, K; Liu, K Y; Liu, Ke; Liu, L; Liu, Lu; Liu, M H; Liu, P L; Liu, Q; Liu, S B; Liu, T; Liu, W K; Liu, W M; Liu, X; Liu, Y; Liu, Y B; Liu, Z A; Liu, Z Q; Lou, X C; Lu, F X; Lu, H J; Lu, J G; Lu, X L; Lu, Y; Lu, Y P; Lu, Z H; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Lyu, Y F; Ma, F C; Ma, H L; Ma, L L; Ma, M M; Ma, Q M; Ma, R Q; Ma, R T; Ma, X Y; Ma, Y; Maas, F E; Maggiora, M; Maldaner, S; Malde, S; Malik, Q A; Mangoni, A; Mao, Y J; Mao, Z P; Marcello, S; Meng, Z X; Messchendorp, J; Mezzadri, G; Miao, H; Min, T J; Mitchell, R E; Mo, X H; Muchnoi, N Yu; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, X; Pan, Y; Pathak, A; Pelizaeus, M; Peng, H P; Peters, K; Ping, J L; Ping, R G; Plura, S; Pogodin, S; Prasad, V; Qi, F Z; Qi, H; Qi, H R; Qi, M; Qi, T Y; Qian, S; Qian, W B; Qian, Z; Qiao, C F; Qin, J J; Qin, L Q; Qin, X P; Qin, X S; Qin, Z H; Qiu, J F; Qu, S Q; Qu, S Q; Rashid, K H; Redmer, C F; Ren, K J; Rivetti, A; Rodin, V; Rolo, M; Rong, G; Rosner, Ch; Ruan, S N; Sang, H S; Sarantsev, A; Schelhaas, Y; Schnier, C; Schoenning, K; Scodeggio, M; Shan, K Y; Shan, W; Shan, X Y; Shangguan, J F; Shao, L G; Shao, M; Shen, C P; Shen, H F; Shen, X Y; Shi, B A; Shi, H C; Shi, J Y; Shi, Q Q; Shi, R S; Shi, X; Shi, X D; Song, J J; Song, W M; Song, Y X; Sosio, S; Spataro, S; Stieler, F; Su, K X; Su, P P; Su, Y J; Sun, G X; Sun, H; Sun, H K; Sun, J F; Sun, L; Sun, S S; Sun, T; Sun, W Y; Sun, X; Sun, Y J; Sun, Y Z; Sun, Z T; Tan, Y H; Tan, Y X; Tang, C J; Tang, G Y; Tang, J; Tao, L Y; Tao, Q T; Tat, M; Teng, J X; Thoren, V; Tian, W H; Tian, Y; Uman, I; Wang, B; Wang, B L; Wang, C W; Wang, D Y; Wang, F; Wang, H J; Wang, H P; Wang, K; Wang, L L; Wang, M; Wang, M Z; Wang, Meng; Wang, S; Wang, S; Wang, T; Wang, T J; Wang, W; Wang, W H; Wang, W P; Wang, X; Wang, X F; Wang, X L; Wang, Y; Wang, Y D; Wang, Y F; Wang, Y H; Wang, Y Q; Wang, Yaqian; Wang, Z; Wang, Z Y; Wang, Ziyi; Wei, D H; Weidner, F; Wen, S P; White, D J; Wiedner, U; Wilkinson, G; Wolke, M; Wollenberg, L; Wu, J F; Wu, L H; Wu, L J; Wu, X; Wu, X H; Wu, Y; Wu, Y J; Wu, Z; Xia, L; Xiang, T; Xiao, D; Xiao, G Y; Xiao, H; Xiao, S Y; Xiao, Y L; Xiao, Z J; Xie, C; Xie, X H; Xie, Y; Xie, Y G; Xie, Y H; Xie, Z P; Xing, T Y; Xu, C F; Xu, C J; Xu, G F; Xu, H Y; Xu, Q J; Xu, X P; Xu, Y C; Xu, Z P; Yan, F; Yan, L; Yan, W B; Yan, W C; Yang, H J; Yang, H L; Yang, H X; Yang, L; Yang, S L; Yang, Tao; Yang, Y F; Yang, Y X; Yang, Yifan; Ye, M; Ye, M H; Yin, J H; You, Z Y; Yu, B X; Yu, C X; Yu, G; Yu, T; Yuan, C Z; Yuan, L; Yuan, S C; Yuan, X Q; Yuan, Y; Yuan, Z Y; Yue, C X; Zafar, A A; Zeng, F R; Zeng, X; Zeng, Y; Zhan, Y H; Zhang, A Q; Zhang, B L; Zhang, B X; Zhang, D H; Zhang, G Y; Zhang, H; Zhang, H H; Zhang, H H; Zhang, H Y; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J X; Zhang, J Y; Zhang, J Z; Zhang, Jianyu; Zhang, Jiawei; Zhang, L M; Zhang, L Q; Zhang, Lei; Zhang, P; Zhang, Q Y; Zhang, Shuihan; Zhang, Shulei; Zhang, X D; Zhang, X M; Zhang, X Y; Zhang, X Y; Zhang, Y; Zhang, Y T; Zhang, Y H; Zhang, Yan; Zhang, Yao; Zhang, Z H; Zhang, Z Y; Zhang, Z Y; Zhao, G; Zhao, J; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, S J; Zhao, Y B; Zhao, Y X; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, Y H; Zhong, B; Zhong, C; Zhong, X; Zhou, H; Zhou, L P; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhou, Y Z; Zhu, J; Zhu, K; Zhu, K J; Zhu, L X; Zhu, S H; Zhu, S Q; Zhu, T J; Zhu, W J; Zhu, Y C; Zhu, Z A; Zou, B S; Zou, J H
File in questo prodotto:
File Dimensione Formato  
PhysRevLett.129.212002.pdf

Accesso aperto

Dimensione 395.46 kB
Formato Adobe PDF
395.46 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1887613
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact