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arXiv · 2611.00385

Current Results on Light Hypernuclei in the WASA-FRS HypHI Experiment

C. Rappold·P. Achenbach·H. Alibrahim Alfaki·F. Amjad·M. Armstrong·K. H. Behr·J. Benlliure·Z. Brencic·D. Calongue González·T. Dickel·V. Drozd·S. Dubey·H. Ekawa·S. Escrig·M. Feijoo-Fontan·H. Fujioka·Y. Gao·H. Geissel·F. Goldenbaum·A. Graña Gonzalez·E. Haettner·M. N. Harakeh·Y. He·H. Heggen·C. Hornung·N. Hubbard·K. Itahashi·M. Iwasaki·N. Kalantar-Nayestanaki·A. Kasagi·M. Kavatsyuk·E. Kazantseva·A. Khreptak·B. Kindler·R. Knoebel·H. Kollmus·D. Kostyleva·S. Kraft-Bermuth·N. Kurz·E. Liu·B. Lommel·V. Metag·S. Minami·D. J. Morrissey·P. Moskal·I. Mukha·A. Muneem·M. Nakagawa·K. Nakazawa·C. Nociforo·H. J. Ong·S. Pietri·J. Pochodzalla·S. Purushothaman·E. Rocco·J. L. Rodríguez-Sánchez·P. Roy·R. Ruber·T. R. Saito·S. Schadmand·C. Scheidenberger·P. Schwarz·R. Sekiya·V. Serdyuk·M. Skurzok·B. Streicher·K. Suzuki·B. Szczepanczyk·Y. K. Tanaka·X. Tang·N. Tortorelli·M. Vencelj·H. Wang·T. Weber·H. Weick·M. Will·K. Wimmer·A. Yamamoto·A. Yanai·J. Yoshida·J. Zhao
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Abstract

The current understanding of light hypernuclei, subatomic nuclei exhibiting strangeness, is being actively investigated by several collaborations. Recent studies employing high-energy heavy-ion beams have revealed unexpected results for the three-body bound state $^3_Λ$H, known as the hypertriton. Experimental measurements of its lifetime and binding energy across multiple experiments have produced a puzzling situation referred to as the ``hypertriton puzzle''. This puzzle is the central focus of the data analysis from the WASA-FRS HypHI experiment at GSI-FAIR within the SuperFRS Experiment collaboration. Light hypernuclei are being investigated using 1.96 GeV/u $^6$Li beams impinging on a fixed carbon target, in conjunction with the WASA detector system and the Fragment Separator (FRS) at GSI-FAIR. The WASA-FRS experimental campaign was carried out during the first quarter of 2022. The primary objective of the experiment is to measure the lifetimes of $^3_Λ$H and $^4_Λ$H. The possible observation of the nn$Λ$ state constitutes the second component of the WASA-FRS research program. This contribution provides an overview of our investigation of hypernuclei. Focusing on the WASA-FRS HypHI experiment, details of the current analysis status are presented.

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C. Rappold, P. Achenbach, H. Alibrahim Alfaki, F. Amjad, M. Armstrong, K. H. Behr, J. Benlliure, Z. Brencic, D. Calongue González, T. Dickel, V. Drozd, S. Dubey, H. Ekawa, S. Escrig, M. Feijoo-Fontan, H. Fujioka, Y. Gao, H. Geissel, F. Goldenbaum, A. Graña Gonzalez, E. Haettner, M. N. Harakeh, Y. He, H. Heggen, C. Hornung, N. Hubbard, K. Itahashi, M. Iwasaki, N. Kalantar-Nayestanaki, A. Kasagi, M. Kavatsyuk, E. Kazantseva, A. Khreptak, B. Kindler, R. Knoebel, H. Kollmus, D. Kostyleva, S. Kraft-Bermuth, N. Kurz, E. Liu, B. Lommel, V. Metag, S. Minami, D. J. Morrissey, P. Moskal, I. Mukha, A. Muneem, M. Nakagawa, K. Nakazawa, C. Nociforo, H. J. Ong, S. Pietri, J. Pochodzalla, S. Purushothaman, E. Rocco, J. L. Rodríguez-Sánchez, P. Roy, R. Ruber, T. R. Saito, S. Schadmand, C. Scheidenberger, P. Schwarz, R. Sekiya, V. Serdyuk, M. Skurzok, B. Streicher, K. Suzuki, B. Szczepanczyk, Y. K. Tanaka, X. Tang, N. Tortorelli, M. Vencelj, H. Wang, T. Weber, H. Weick, M. Will, K. Wimmer, A. Yamamoto, A. Yanai, J. Yoshida, J. Zhao. 2026-10-30. Current Results on Light Hypernuclei in the WASA-FRS HypHI Experiment. https://arxiv.org/abs/2611.00385

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