Measurement of the H-3(Lambda) lifetime in Au plus Au collisions at the BNL Relativistic Heavy Ion Collider

0490149 - ÚJF 2019 RIV US eng J - Journal Article
Adamczyk, L. - Bielčík, J. - Bielčíková, Jana - Chaloupka, P. - Federič, Pavol - Federičová, P. - Harlenderová, A. - Kocmánek, Martin - Kvapil, J. - Lidrych, J. - Rusňák, Jan - Rusňáková, O. - Šaur, Miroslav - Šimko, Miroslav - Šumbera, Michal - Trzeciak, B. A. … Total 345 authors
Measurement of the H-3(Lambda) lifetime in Au plus Au collisions at the BNL Relativistic Heavy Ion Collider.
Physical Review C. Roč. 97, č. 5 (2018), č. článku 054909. ISSN 2469-9985. E-ISSN 2469-9993
R&D Projects: GA MŠMT EF16_013/0001569
Institutional support: RVO:61389005
Keywords : STAR collaboration * H-3(Lamda) * RHIC
OECD category: Nuclear physics
Impact factor: 3.132, year: 2018

An improved measurement of the H-3(Lambda) lifetime is presented. In this paper, the mesonic decay modes H-3(Lambda) -> He-3 + pi(-) and H-3(Lambda) -> d + p + pi(-) are used to reconstruct the H-3(Lambda) from Au+Au collision data collected by the STAR collaboration at Relativistic Heavy Ion Collider (RHIC) A minimum chi(2) estimation is used to determine the lifetime tau = 142(+21)(-24 )(stat.)+/- 29 (syst.) ps. This lifetime is about 50% shorter than the lifetime tau = 263 +/- 2 ps of a free A, indicating strong hyperon-nucleon interaction in the hypernucleus system. The branching ratios of the mesonic decay channels are also determined to satisfy B.R.(He-3+ pi(-))/(B.R.(H-3+pi(-))/B.R.((d+p+pi))) = 0.32 +/- 0.05 (stat.)+/- 0.08 (syst.). Our ratio result favors the assignment J(H-3(Lambda)) = 1/2 over J(H-3(Lambda)) = 3/2. These measurements will help to constrain models of hyperon-baryon interactions.
Permanent Link: http://hdl.handle.net/11104/0284445