Disentangling Centrality Bias and Final-State Effects in the Production of High-pT Neutral Pions Using Direct Photon in d plus Au Collisions at root sNN=200 GeV

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F25%3A00390373" target="_blank" >RIV/68407700:21340/25:00390373 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1103/PhysRevLett.134.022302" target="_blank" >https://doi.org/10.1103/PhysRevLett.134.022302</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevLett.134.022302" target="_blank" >10.1103/PhysRevLett.134.022302</a>

Result language

angličtina

Original language name

Disentangling Centrality Bias and Final-State Effects in the Production of High-pT Neutral Pions Using Direct Photon in d plus Au Collisions at root sNN=200 GeV

Original language description

PHENIX presents a simultaneous measurement of the production of direct gamma and pi(0) in d + Au collisions at root S-NN = 200 GeV over a p(T) range of 7.5 to 18 GeV/c for different event samples selected by event activity, i.e., charged-particle multiplicity detected at forward rapidity. Direct-photon yields are used to empirically estimate the contribution of hard-scattering processes in the different event samples. Using this estimate, the average nuclear-modification factor, R-dAu,EXP(pi 0) is 0.925 +/- 0.023(stat) +/- 0.15(scale), consistent with unity for minimum- bias (MB) d + Au collisions. For event classes with low and moderate event activity, R-dAu,EXP(pi 0) is consistent with the MB value within 5% uncertainty. This result confirms that the previously observed enhancement of high-pT pi(0) production found in small-system collisions with low event activity is a result of a bias in interpreting event activity within the Glauber framework. In contrast, for the top 5% of events with the highest event activity, R-dAu,EXP(pi 0) is suppressed by 20% relative to the MB value with a significance of 4.5s, which may be due to final-state effects. This suppression corresponds to a p(T) shift of delta p(T) = 0.213 +/- 0.055 Gev/c at 9 Gev/c.

Czech name

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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

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OECD FORD branch

10303 - Particles and field physics

Project

—

Continuities

—

Publication year

2025

Confidentiality

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

Name of the periodical

Physical Review Letters

ISSN

0031-9007

e-ISSN

1079-7114

Volume of the periodical

134

Issue of the periodical within the volume

2

Country of publishing house

US - UNITED STATES

Number of pages

9

Pages from-to

1-9

UT code for WoS article

001413548700001

EID of the result in the Scopus database

2-s2.0-85215390612