First Observation of $Λπ^+$ and $Λπ^-$ Signals near the $\bar{K}N (I=1)$ Mass Threshold in $Λ_c^+\rightarrowΛπ^+π^+π^-$ Decay
Creators: name: Belle Collaboration
name: Ma, Y.
name: Yelton, J.
name: Tanida, K.
name: Adachi, I.
name: Ahn, J. K.
name: Aihara, H.
name: Said, S. Al
name: Asner, D. M.
name: Atmacan, H.
name: Aushev, T.
name: Ayad, R.
name: Babu, V.
name: Bahinipati, S.
name: Banerjee, Sw.
name: Behera, P.
name: Belous, K.
name: Bennett, J.
name: Bessner, M.
name: Bhuyan, B.
name: Bilka, T.
name: Biswas, D.
name: Bobrov, A.
name: Bodrov, D.
name: Borah, J.
name: Bozek, A.
name: Bračko, M.
name: Branchini, P.
name: Browder, T. E.
name: Budano, A.
name: Campajola, M.
name: Červenkov, D.
name: Chang, M. -C.
name: Chen, A.
name: Cheon, B. G.
name: Chilikin, K.
name: Cho, H. E.
name: Cho, K.
name: Cho, S. -J.
name: Choi, S. -K.
name: Choi, Y.
name: Choudhury, S.
name: Cinabro, D.
name: Das, S.
name: De Nardo, G.
name: De Pietro, G.
name: Dhamija, R.
name: Di Capua, F.
name: Dingfelder, J.
name: Doležal, Z.
name: Dong, T. V.
name: Epifanov, D.
name: Ferber, T.
name: Ferlewicz, D.
name: Fulsom, B. G.
name: Garg, R.
name: Gaur, V.
name: Garmash, A.
name: Giri, A.
name: Goldenzweig, P.
name: Golob, B.
name: Graziani, E.
name: Gudkova, K.
name: Hadjivasiliou, C.
name: Halder, S.
name: Hayasaka, K.
name: Hayashii, H.
name: Hedges, M. T.
name: Hou, W. -S.
name: Hsu, C. -L.
name: Inami, K.
name: Ipsita, N.
name: Ishikawa, A.
name: Itoh, R.
name: Iwasaki, M.
name: Jacobs, W. W.
name: Jang, E. -J.
name: Jia, S.
name: Jin, Y.
name: Kaliyar, A. B.
name: Kang, K. H.
name: Kawasaki, T.
name: Kiesling, C.
name: Kim, C. H.
name: Kim, D. Y.
name: Kim, Y. -K.
name: Kinoshita, K.
name: Kodyš, P.
name: Korobov, A.
name: Korpar, S.
name: Kovalenko, E.
name: Križan, P.
name: Krokovny, P.
name: Kumar, R.
name: Kumara, K.
name: Kwon, Y. -J.
name: Lam, T.
name: Lange, J. S.
name: Lee, S. C.
name: Lewis, P.
name: Li, L. K.
name: Li, Y.
name: Gioi, L. Li
name: Libby, J.
name: Lieret, K.
name: Lin, Y. -R.
name: Liventsev, D.
name: Luo, T.
name: Masuda, M.
name: Matsuda, T.
name: Matvienko, D.
name: Maurya, S. K.
name: Meier, F.
name: Merola, M.
name: Metzner, F.
name: Miyabayashi, K.
name: Mohanty, G. B.
name: Mussa, R.
name: Nakamura, I.
name: Nakano, T.
name: Nakao, M.
name: Natkaniec, Z.
name: Natochii, A.
name: Nayak, L.
name: Nayak, M.
name: Nisar, N. K.
name: Nishida, S.
name: Ogawa, S.
name: Ono, H.
name: Oskin, P.
name: Pakhlov, P.
name: Pakhlova, G.
name: Pardi, S.
name: Park, H.
name: Park, J.
name: Patra, S.
name: Paul, S.
name: Pestotnik, R.
name: Piilonen, L. E.
name: Podobnik, T.
name: Prencipe, E.
name: Prim, M. T.
name: Rostomyan, A.
name: Rout, N.
name: Russo, G.
name: Sandilya, S.
name: Santelj, L.
name: Savinov, V.
name: Schnell, G.
name: Schueler, J.
name: Schwanda, C.
name: Seino, Y.
name: Senyo, K.
name: Sevior, M. E.
name: Shan, W.
name: Shapkin, M.
name: Sharma, C.
name: Shen, C. P.
name: Shiu, J. -G.
name: Simon, F.
name: Sokolov, A.
name: Solovieva, E.
name: Starič, M.
name: Sumihama, M.
name: Sumiyoshi, T.
name: Sutcliffe, W.
name: Takizawa, M.
name: Tamponi, U.
name: Tenchini, F.
name: Uchida, M.
name: Uehara, S.
name: Uglov, T.
name: Unno, Y.
name: Uno, K.
name: Uno, S.
name: Urquijo, P.
name: Usov, Y.
name: Vahsen, S. E.
name: van Tonder, R.
name: Varner, G.
name: Vinokurova, A.
name: Vossen, A.
name: Wang, D.
name: Wang, M. -Z.
name: Watanabe, M.
name: Watanuki, S.
name: Werbycka, O.
name: Won, E.
name: Xu, X.
name: Yabsley, B. D.
name: Yan, W.
name: Yang, S. B.
name: Yin, J. H.
name: Yuan, C. Z.
name: Yuan, L.
name: Zhang, Z. P.
name: Zhilich, V.
name: Zhukova, V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Using the data sample of 980 fb$^{-1}$ collected with the Belle detector operating at the KEKB asymmetric-energy $e^+e^-$ collider, we present the results of an investigation of the $Λπ^+$ and $Λπ^-$ invariant mass distributions looking for substructure in the decay $Λ_c^+\rightarrowΛπ^+π^+π^-$. We find a significant signal in each mass dis\ tribution. When interpreted as resonances, we find for the $Λπ^+$ ($Λπ^-$) combination a mass of $1434.3 \pm 0.6 (\mathrm{stat}) \pm 0.9(\mathrm{syst})$ MeV/$c^2$ [$1438.5 \pm 0.9 (\mathrm{stat}) \pm 2.5(\mathrm{syst})$ MeV/$c^2$], an intrinsic width of $11.5 \pm 2.8 (\mathrm{stat}) \pm 5.3(\mathrm{syst})$ MeV/$c^2$ [$33.0 \pm 7.5 (\mathrm{stat}) \pm 23.6(\mathrm{syst})$ MeV/$c^2$] with a significance of 7.5$σ$ (6.2$σ$). As these two signals are very close to the $\bar{K}N$ threshold, we also investigate the possibility of a $\bar{K}N$ cusp, and find that \ we cannot discriminate between these two interpretations due to the limited size of the data sample.