Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over â]+p[over â] Collisions.
Phys Rev Lett
; 130(25): 251901, 2023 Jun 23.
Article
in En
| MEDLINE
| ID: mdl-37418716
ABSTRACT
We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over â]+p[over â] 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
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Photons
/
Food
Language:
En
Journal:
Phys Rev Lett
Year:
2023
Document type:
Article
Affiliation country:
Hungary