{"paper":{"title":"Observation of Spin-Dependent Charge Symmetry Breaking in $\\Lambda N$ Interaction: Gamma-Ray Spectroscopy of $^4_{\\Lambda }$He","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["nucl-th"],"primary_cat":"nucl-ex","authors_text":"A. Feliciello, A. Sakaguchi, E. Botta, H. Ekawa, H. Sako, H. Sugimura, H. Tamura, J .Y. Lee, K. Aoki, K. Hosomi, K. Imai, K. Miwa, K. Shirotori, K. Tanabe, K. Tanida, M. Agnello, M. Fujita, M. H. Kim, M. Ikeda, M. Nakagawa, M. Ukai, N. Amano, N. Chiga, N. Ichige, P. Evtoukhovitch, R. Honda, S. B. Yang, S. Hasegawa, S. H. Hayakawa, S .H. Hwang, S. H. Kim, S. Ishimoto, S. Kanatsuki, S. Kinbara, S. Marcello, S. Nagao, S. Sato, S. Suto, S. Suzuki, T. Gogami, T. Hayakawa, T. Koike, T. Moon, T. Nagae, T. O. Yamamoto, T. Shiozaki, T. Takahashi, Y. Akazawa, Y. Ichikawa, Y. Nakada, Y. Ogura, Y. Sasaki, Y. Yamamoto, Z. Tsamalaidze","submitted_at":"2015-08-03T11:21:31Z","abstract_excerpt":"The energy spacing between the ground-state spin doublet of $^4_\\Lambda $He(1$^+$,0$^+$) was determined to be $1406 \\pm 2 \\pm 2$ keV, by measuring $\\gamma$ rays for the $1^+ \\to 0^+$ transition with a high efficiency germanium detector array in coincidence with the $^4$He$(K^-,\\pi^-)$ $^4_\\Lambda $He reaction at J-PARC. In comparison to the corresponding energy spacing in the mirror hypernucleus $^4_\\Lambda $H, the present result clearly indicates the existence of charge symmetry breaking (CSB) in $\\Lambda N$ interaction. It is also found that the CSB effect is large in the $0^+$ ground state "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.00376","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}