******** CTC Particle Physics Seminar ********

Speaker： Dr. Ralf Seidl (RIKEN Japan)

Title ： An Introduction to sPHENIX and its cold-QCD program

Time ： 10:30-11:30, Thursday, 2023/8/31

Place ： P512, 5F, 3rd General Building, Nat'l Tsing Hua Univ.

Host ： Prof. Po-Ju Lin (NCU)

Abstract:
The visible mass of the universe is generated by the strong interaction
with its constituents, the quarks, and its mediators, the gluons.
Studying the (spin) structure of its bound states, nucleons and nuclei,
provides insights into this interaction that cannot be accessed from
first-principle calculations.
In hadronic collisions the hard interactions are predominantly mediated
by the strong interaction. This provides leading order access to gluon
distributions in the nucleon and nuclei. In polarized hadronic
collisions one is therefore able to probe spin-orbit correlations of
gluons via single spin asymmetries of heavy flavor or direct photon
production. Also the transverse polarization of quarks in the nucleon
can be probed via azimuthal asymmetries of hadron pairs or hadrons
within jets.
The sPHENIX experiment has been constructed to build on the experience
of the previous RHIC experiments at Brookhaven National Lab and
concentrates on high-rate jet capabilities and precise tracking at
central rapidities.
In this colloquium I will present the cold QCD physics motivations, the
sPHENIX detector, its commissioning status from the 2023 RHIC running
period and expected precision of key cold QCD measurements.