Inclusive cross section and double helicity asymmetry for Pi0 production in p+p collisions at sqrt(s)=200 GeV: Implications for the polarized gluon distribution in the proton

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F07%3A00146823" target="_blank" >RIV/68407700:21340/07:00146823 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/07:10084091

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Inclusive cross section and double helicity asymmetry for Pi0 production in p+p collisions at sqrt(s)=200 GeV: Implications for the polarized gluon distribution in the proton

Popis výsledku v původním jazyce

The PHENIX experiment presents results from the Relativistic Heavy Ion Collider 2005 run with polarized proton collisions at root s=200 GeV, for inclusive pi(0) production at midrapidity. Unpolarized cross section results are given for transverse momentap(T)=0.5 to 20 GeV/c, extending the range of published data to both lower and higher p(T). The cross section is described well for p(T)< 1 GeV/c by an exponential in p(T), and, for p(T)> 2 GeV/c, by perturbative QCD. Double helicity asymmetries A(LL) are presented based on a factor of 5 improvement in uncertainties as compared to previously published results, due to both an improved beam polarization of 50%, and to higher integrated luminosity. These measurements are sensitive to the gluon polarizationin the proton. Using one representative model of gluon polarization it is demonstrated that the gluon spin contribution to the proton spin is significantly constrained.

Název v anglickém jazyce

Inclusive cross section and double helicity asymmetry for Pi0 production in p+p collisions at sqrt(s)=200 GeV: Implications for the polarized gluon distribution in the proton

Popis výsledku anglicky

The PHENIX experiment presents results from the Relativistic Heavy Ion Collider 2005 run with polarized proton collisions at root s=200 GeV, for inclusive pi(0) production at midrapidity. Unpolarized cross section results are given for transverse momentap(T)=0.5 to 20 GeV/c, extending the range of published data to both lower and higher p(T). The cross section is described well for p(T)< 1 GeV/c by an exponential in p(T), and, for p(T)> 2 GeV/c, by perturbative QCD. Double helicity asymmetries A(LL) are presented based on a factor of 5 improvement in uncertainties as compared to previously published results, due to both an improved beam polarization of 50%, and to higher integrated luminosity. These measurements are sensitive to the gluon polarizationin the proton. Using one representative model of gluon polarization it is demonstrated that the gluon spin contribution to the proton spin is significantly constrained.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BF - Elementární částice a fyzika vysokých energií

OECD FORD obor

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Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

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

Rok uplatnění

2007

Kód důvěrnosti údajů

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

Název periodika

Physical Review D

ISSN

1550-7998

e-ISSN

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Svazek periodika

76

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

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Kód UT WoS článku

000249786800006

EID výsledku v databázi Scopus

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