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

Kód výsledku v 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>

Výsledek na webu

<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>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

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

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

<a href="/cs/project/LM2023034" target="_blank" >LM2023034: Brookhavenská národní laboratoř – účast České republiky</a><br>

Návaznosti

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

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název periodika

Nature

ISSN

0028-0836

e-ISSN

1476-4687

Svazek periodika

632

Číslo periodika v rámci svazku

8027

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

6

Strana od-do

1026-1031

Kód UT WoS článku

001373611600001

EID výsledku v databázi Scopus

2-s2.0-85202579268