Speaker
Description
At RHIC energies high pT direct photons are mainly produced by the
quark-gluon Compton scattering process. Being not disturbed by fragmentation
processes, they provide access to initial condition of partonic collisions.
Direct photon production in pp collisions serves an ideal probe for gluon
parton distribution functions (PDF), whereas quark PDFs are well constrained
by deeply inelastic lepton-nucleon scattering. Similarly, longitudinally
polarized pp collisions provide direct access to gluon helicity distribution
within the proton, and therefore contribute to resolving the long standing
puzzle of the proton spin decomposition. We will present the status of the
direct photon analysis from pp collisions at sqrt(s)=510 GeV by PHENIX for
both unpolarized and helicity dependent measurements, and comparison to
previous measurements at different sqrt(s) and to NLO pQCD calculations
| Contribution type | Contributed Talk |
|---|---|
| Track | Electroweak Probes |
| Collaboration (if applicable) | PHENIX |
