Abstract
An improved measurement of the HΛ3 lifetime is presented. In this paper, the mesonic decay modes HΛ3→He3 + π- and HΛ3→d+p+π- are used to reconstruct the HΛ3 from Au+Au collision data collected by the STAR collaboration at Relativistic Heavy Ion Collider (RHIC). A minimum χ2 estimation is used to determine the lifetime of τ=142-21+24(stat.)±29(syst.) ps. This lifetime is about 50% shorter than the lifetime τ=263±2 ps of a free Λ, indicating strong hyperon-nucleon interaction in the hypernucleus system. The branching ratios of the mesonic decay channels are also determined to satisfy B.R.(He3+π-)/(B.R.(He3+π-)+B.R.(d+p+π-))=0.32±0.05(stat.)±0.08(syst.). Our ratio result favors the assignment J(HΛ3)=12 over J(HΛ3)=32. These measurements will help to constrain models of hyperon-baryon interactions.
Original language | English |
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Article number | 054909 |
Journal | Physical Review C |
Volume | 97 |
Issue number | 5 |
DOIs | |
State | Published - May 22 2018 |
Externally published | Yes |
Funding
We thank the RHIC Operations Group and RCF at BNL, the NERSC Center at LBNL, and the Open Science Grid consortium for providing resources and support. This work was supported in part by the Office of Nuclear Physics within the US DOE Office of Science, the US National Science Foundation, the Ministry of Education and Science of the Russian Federation, National Natural Science Foundation of China, Chinese Academy of Science, the Ministry of Science and Technology of China (973 Program No. 2014CB845400) and the Chinese Ministry of Education, the National Research Foundation of Korea, GA and MSMT of the Czech Republic, Department of Atomic Energy and Department of Science and Technology of the Government of India, the National Science Centre of Poland, National Research Foundation, the Ministry of Science, Education and Sports of the Republic of Croatia, RosAtom of Russia and German Bundesministerium fur Bildung, Wissenschaft, Forschung and Technologie (BMBF), and the Helmholtz Association.
Funders | Funder number |
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RosAtom of Russia and German Bundesministerium fur Bildung, Wissenschaft, Forschung and Technologie | |
National Science Foundation | 1613939 |
Office of Science | |
Nuclear Physics | |
National Research Foundation | |
Department of Science and Technology, Ministry of Science and Technology, India | |
National Natural Science Foundation of China | |
Ministerstvo Školství, Mládeže a Tělovýchovy | |
Ministry of Education of the People's Republic of China | |
Bundesministerium für Bildung und Forschung | |
Chinese Academy of Sciences | |
Ministry of Science and Technology of the People's Republic of China | 2014CB845400 |
Ministarstvo Obrazovanja, Znanosti i Sporta | |
Ministry of Education and Science of the Russian Federation | |
Narodowe Centrum Nauki | |
Helmholtz Association |