Observation of a Be double-Lambda hypernucleus in the J-PARC E07 experiment. (22nd February 2019)

• Record Type: Journal Article
• Authors: Ekawa, H; Agari, K; Ahn, J K; Akaishi, T; Akazawa, Y; Ashikaga, S; Bassalleck, B; Bleser, S; Endo, Y; Fujikawa, Y; Fujioka, N; Fujita, M; Goto, R; Han, Y; Hasegawa, S; Hashimoto, T; Hayakawa, S H; Hayakawa, T; Hayata, E; Hicks, K; Hirose, E; Hirose, M; Honda, R; Hoshino, K; Hoshino, S; Hosomi, K; Hwang, S H; Ichikawa, Y; Ichikawa, M; Ieiri, M; Imai, K; Inaba, K; Ishikawa, Y; Iskendir, A; Ito, H; Ito, K; Jung, W S; Kanatsuki, S; Kanauchi, H; Kasagi, A; Kawai, T; Kim, M H; Kim, S H; Kinbara, S; Kiuchi, R; Kobayashi, H; Kobayashi, K; Koike, T; Koshikawa, A; Lee, J Y; Lee, J W; Ma, T L; Matsumoto, S Y; Minakawa, M; Miwa, K; Moe, A T; Moon, T J; Moritsu, M; Nagase, Y; Nakada, Y; Nakagawa, M; Nakashima, D; Nakazawa, K; Nanamura, T; Naruki, M; Nyaw, A N L; Ogura, Y; Ohashi, M; Oue, K; Ozawa, S; Pochodzalla, J; Ryu, S Y; Sako, H; Sasaki, Y; Sato, S; Sato, Y; Schupp, F; Shirotori, K; Soe, M M; Soe, M K; Sohn, J Y; Sugimura, H; Suzuki, K N; Takahashi, H; Takahashi, T; Takahashi, Y; Takeda, T; Tamura, H; Tanida, K; Theint, A M M; Tint, K T; Toyama, Y; Ukai, M; Umezaki, E; Watabe, T; Watanabe, K; Yamamoto, T O; Yang, S B; Yoon, C S; Yoshida, J; Yoshimoto, M; Zhang, D H; Zhang, Z;
• Is Part Of: Progress of theoretical and experimental physics. Volume 2019:Number 2(2019)
• Publication Date: 2019-02-22
• Subjects: D14; Physics -- Periodicals; Mathematical physics -- Periodicals; 530.05
• DOI: 10.1093/ptep/pty149
• Languages: English
• ISSNs: 2050-3911

Abstract

Abstract: A double-$\Lambda$ hypernucleus, ${}_{\Lambda\Lambda}\mathrm{Be}$, was observed by the J-PARC E07 Collaboration in nuclear emulsions tagged by the ($K^{-}, K^{+}$ ) reaction. This event was interpreted as the production and decay of $ {}_{\Lambda\Lambda}^{\;10}\mathrm{Be}$, ${}_{\Lambda\Lambda}^{\;11}\mathrm{Be}$, or ${}_{\Lambda\Lambda}^{\;12}\mathrm{Be}^{*}$ via $\Xi^{-}$ capture in ${}^{16}\mathrm{O}$ . By assuming capture in the atomic 3D state, the binding energies of two $\Lambda$ hyperons ($B_{\Lambda\Lambda}$ ) of these double-$\Lambda$ hypernuclei are obtained to be $15.05 \pm 0.11\, \mathrm{MeV}$, $19.07 \pm 0.11\, \mathrm{MeV}$, and $13.68 \pm 0.11\, \mathrm{MeV}$, respectively. Based on the kinematic fitting, ${}_{\Lambda\Lambda}^{\;11}\mathrm{Be}$ is the most likely explanation for the observed event.