Observation of the antimatter hypernucleus ¯Λ4¯H

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F24%3A00603090" target="_blank" >RIV/61389005:_____/24:00603090 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1038/s41586-024-07823-0" target="_blank" >https://doi.org/10.1038/s41586-024-07823-0</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1038/s41586-024-07823-0" target="_blank" >10.1038/s41586-024-07823-0</a>

Result language

angličtina

Original language name

Observation of the antimatter hypernucleus ¯Λ4¯H

Original language description

At the origin of the Universe, an asymmetry between the amount of created matter and antimatter led to the matter-dominated Universe as we know it today. The origins of this asymmetry remain unknown so far. High-energy nuclear collisions create conditions similar to the Universe microseconds after the Big Bang, with comparable amounts of matter and antimatter1–6. Much of the created antimatter escapes the rapidly expanding fireball without annihilating, making such collisions an effective experimental tool to create heavy antimatter nuclear objects and to study their properties7–14, hoping to shed some light on the existing questions on the asymmetry between matter and antimatter. Here we report the observation of the antimatter hypernucleus H¯Λ¯4, composed of a Λ¯, an antiproton and two antineutrons. The discovery was made through its two-body decay after production in ultrarelativistic heavy-ion collisions by the STAR experiment at the Relativistic Heavy Ion Collider15,16. In total, 15.6 candidate H¯Λ¯4 antimatter hypernuclei are obtained with an estimated background count of 6.4. The lifetimes of the antihypernuclei H¯Λ¯3 and H¯Λ¯4 are measured and compared with the lifetimes of their corresponding hypernuclei, testing the symmetry between matter and antimatter. Various production yield ratios among (anti)hypernuclei (hypernuclei and/or antihypernuclei) and (anti)nuclei (nuclei and/or antinuclei) are also measured and compared with theoretical model predictions, shedding light on their production mechanisms.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10303 - Particles and field physics

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Nature

ISSN

0028-0836

e-ISSN

1476-4687

Volume of the periodical

632

Issue of the periodical within the volume

8027

Country of publishing house

GB - UNITED KINGDOM

Number of pages

6

Pages from-to

1026-1031

UT code for WoS article

001373611600001

EID of the result in the Scopus database

2-s2.0-85202579268