PHENIX measurement of the high pT direct photon production in p+A collisions and its implication to the initial state of the system

Jun 2, 2020, 7:30 AM
1h 20m


Poster Presentation Electroweak Probes Poster session


Niveditha Ramasubramanian (Stony Brook University)


High transverse momentum direct photons are penetrating probes in
relativistic heavy ion collisions. Once produced, they leave the collision
region virtually unaffected, even if a hot, dense partonic medium was
formed. This is also the reason why direct photons are immune to the
suppression observed for high pT hadrons and jets in heavy ion collisions,
but can probe the initial state effects. The nuclear modification factor of
high pT photons has been found consistent with unity in Au+Au collisions. It
is of interest whether this applies to not only for p+p and A+A but also for
p+A collisions, especially the most central collisions. Comparing the
centrality dependence of direct photon and hadron production in p+Au system
will provide a test of the applicability of the Glauber model in such
systems which has indeed been an interesting question. The talk will present
the first measurement of high pT photons in this asymmetric collision

Contribution type Contributed Talk
Track Electroweak Probes
Collaboration (if applicable) PHENIX

Primary author

Gabor David (Brookhaven National Laboratory)

Presentation materials