Abstract
According to the CPT theorem, which states that the combined operation of charge conjugation, parity transformation and time reversal must be conserved, particles and their antiparticles should have the same mass and lifetime but opposite charge and magnetic moment. Here, we test CPT symmetry in a nucleus containing a strange quark, more specifically in the hypertriton. This hypernucleus is the lightest one yet discovered and consists of a proton, a neutron and a Λ hyperon. With data recorded by the STAR detector1–3 at the Relativistic Heavy Ion Collider, we measure the Λ hyperon binding energy BΛ for the hypertriton, and find that it differs from the widely used value4 and from predictions5–8, where the hypertriton is treated as a weakly bound system. Our results place stringent constraints on the hyperon–nucleon interaction9,10 and have implications for understanding neutron star interiors, where strange matter may be present11. A precise comparison of the masses of the hypertriton and the antihypertriton allows us to test CPT symmetry in a nucleus with strangeness, and we observe no deviation from the expected exact symmetry.
Original language | English |
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Pages (from-to) | 409-412 |
Number of pages | 4 |
Journal | Nature Physics |
Volume | 16 |
Issue number | 4 |
DOIs | |
State | Published - Apr 1 2020 |
Bibliographical note
Publisher Copyright:© 2020, The Author(s), under exclusive licence to Springer Nature Limited.
Funding
The STAR Collaboration acknowledges contributions from V. Dexheimer, F. Hildenbrand and H.-W. Hammer. We thank the Relativistic Heavy Ion Collider (RHIC) Operations Group and the RHIC Computing Facility (RCF) at Brookhaven National Laboratory (BNL), the National Energy Research Scientific Computing (NERSC) Center at Lawrence Berkeley National Laboratory 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 Department of Energy Office of Science, the US National Science Foundation, the Ministry of Education and Science of the Russian Federation, the National Natural Science Foundation of China, Chinese Academy of Science, the Ministry of Science and Technology of China and the Chinese Ministry of Education, the National Research Foundation of Korea, the Czech Science Foundation and Ministry of Education, Youth and Sports of the Czech Republic, the Hungarian National Research, Development and Innovation Office, the New National Excellency Programme of the Hungarian Ministry of Human Capacities, the Department of Atomic Energy and Department of Science and Technology of the Government of India, the National Science Centre of Poland, the Ministry of Science, Education and Sports of the Republic of Croatia, RosAtom of Russia and the German Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (BMBF) and the Helmholtz Association.
Funders | Funder number |
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Department of Atomic Energy and Department of Science and Technology | |
Hungarian Ministry of Human Capacities | |
RosAtom of Russia | |
National Science Foundation (NSF) | 1913789 |
Office of Science Programs | |
Institute for Nuclear Physics | |
National Natural Science Foundation of China (NSFC) | |
Ministerstvo Školství, Mládeže a Tělovýchovy | |
Grantová Agentura České Republiky | |
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 | |
Ministarstvo Obrazovanja, Znanosti i Sporta | |
Ministry for Education and Science of the Russian Federation | |
National Research Foundation of Korea | |
Narodowe Centrum Nauki | |
Max Delbrück Center for Molecular Medicine in the Helmholtz Association | |
Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie | |
Nemzeti Kutatási Fejlesztési és Innovációs Hivatal |
ASJC Scopus subject areas
- General Physics and Astronomy