Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over →]+p[over →] Collisions.
Journal
Physical review letters
ISSN: 1079-7114
Titre abrégé: Phys Rev Lett
Pays: United States
ID NLM: 0401141
Informations de publication
Date de publication:
23 Jun 2023
23 Jun 2023
Historique:
received:
17
02
2022
revised:
04
11
2022
accepted:
28
04
2023
medline:
10
7
2023
pubmed:
7
7
2023
entrez:
7
7
2023
Statut:
ppublish
Résumé
We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510 GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510 GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02<x<0.08, with direct sensitivity to the sign of the gluon contribution.
Identifiants
pubmed: 37418716
doi: 10.1103/PhysRevLett.130.251901
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM