Azimuthally Differential Pion Femtoscopy in Pb-Pb Collisions at root s(NN)=2.76 TeV

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F17%3A00475704" target="_blank" >RIV/61389005:_____/17:00475704 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/17:00475704 RIV/68407700:21340/17:00318492

Výsledek na webu

<a href="http://dx.doi.org/10.1103/PhysRevLett.118.222301" target="_blank" >http://dx.doi.org/10.1103/PhysRevLett.118.222301</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevLett.118.222301" target="_blank" >10.1103/PhysRevLett.118.222301</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Azimuthally Differential Pion Femtoscopy in Pb-Pb Collisions at root s(NN)=2.76 TeV

Popis výsledku v původním jazyce

We present the first azimuthally differential measurements of the pion source size relative to the second harmonic event plane in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of root(NN)-N-s = 2.76 TeV. The measurements have been performed in the centrality range 0%-50% and for pion pair transverse momenta 0.2 < k(T) < 0.7 GeV/c. We find that the R-side and R-out radii, which characterize the pion source size in the directions perpendicular and parallel to the pion transverse momentum, oscillate out of phase, similar to what was observed at the Relativistic Heavy Ion Collider. The final-state source eccentricity, estimated via R-side oscillations, is found to be significantly smaller than the initial-state source eccentricity, but remains positive-indicating that even after a stronger expansion in the in-plane direction, the pion source at the freeze-out is still elongated in the out-of-plane direction. The 3 + 1D hydrodynamic calculations are in qualitative agreement with observed centrality and transverse momentum R-side oscillations, but systematically underestimate the oscillation magnitude.

Název v anglickém jazyce

Azimuthally Differential Pion Femtoscopy in Pb-Pb Collisions at root s(NN)=2.76 TeV

Popis výsledku anglicky

We present the first azimuthally differential measurements of the pion source size relative to the second harmonic event plane in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of root(NN)-N-s = 2.76 TeV. The measurements have been performed in the centrality range 0%-50% and for pion pair transverse momenta 0.2 < k(T) < 0.7 GeV/c. We find that the R-side and R-out radii, which characterize the pion source size in the directions perpendicular and parallel to the pion transverse momentum, oscillate out of phase, similar to what was observed at the Relativistic Heavy Ion Collider. The final-state source eccentricity, estimated via R-side oscillations, is found to be significantly smaller than the initial-state source eccentricity, but remains positive-indicating that even after a stronger expansion in the in-plane direction, the pion source at the freeze-out is still elongated in the out-of-plane direction. The 3 + 1D hydrodynamic calculations are in qualitative agreement with observed centrality and transverse momentum R-side oscillations, but systematically underestimate the oscillation magnitude.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10304 - Nuclear physics

Projekt

<a href="/cs/project/LG15052" target="_blank" >LG15052: Zkoumání mikrosvěta s využitím infrastruktury CERN</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Physical Review Letters

ISSN

0031-9007

e-ISSN

—

Svazek periodika

118

Číslo periodika v rámci svazku

22

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

—

Kód UT WoS článku

000402681500003

EID výsledku v databázi Scopus

2-s2.0-85020383731