Observation of the antimatter hypernucleus (Λ)over-bar4(H)over bar>

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F24%3A00380169" target="_blank" >RIV/68407700:21340/24:00380169 - 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 (Λ)over-bar4(H)over bar>

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 antimatter(1-6). 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 properties(7-14), 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 4/Lambda(H) over bar, composed of a (Lambda) over bar, 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 Collider(15,16). In total, 15.6 candidate 4/Lambda(H) over bar antimatter hypernuclei are obtained with an estimated background count of 6.4. The lifetimes of the antihypernuclei 3/Lambda(H) over bar and 4/Lambda(H) over tilde 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

—

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

<a href="/en/project/LM2023034" target="_blank" >LM2023034: Brookhaven National Laboratory - Participation of the Czech Republic</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

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