Apr 16 – 20, 2018
Kobe University Convention Centre / Kobe International Conference Center
Asia/Tokyo timezone

Inclusive Jet Measurements in Longitudinally Polarized Proton-Proton Collisions at STAR

Apr 18, 2018, 12:00 PM


WG6: Spin and 3D structure WG6: Spin and 3D structure


Zilong Chang (BNL)


Jet production in high energy proton-proton ($pp$) collisions is dominated by hard QCD scatterings such as gluon-gluon ($gg$) and quark-gluon ($qg$) scatterings, and therefore an effective tool to probe the internal distribution of gluons in the proton. The STAR Collaboration at Relativistic Heavy Ion Collider (RHIC) is using longitudinally polarized $pp$ collisions at center of mass energies, $\sqrt{s} = $ 200 and 510 GeV, to study the production cross-section and double helicity spin asymmetry, $A_{LL}$, of inclusive jet and di-jet productions. The inclusive jet and di-jet cross-section measurements by STAR at $\sqrt{s} = $ 200 GeV showed the jet cross-section is consistent with next-to-leading-order perturbative QCD calculations after underlying event and hadronic corrections. The STAR 2009 inclusive jet $A_{LL}$ measurement in mid-pseudo-rapidity range, $|\eta| < $ 1.0, at $\sqrt{s} = $ 200 GeV showed the first experimental evidence of an non-zero gluon polarization for Bjorken-$x$, $x > 0.05$. The inclusive jet $A_{LL}$ measurements at $\sqrt{s} = $ 510 GeV allow to explore the gluon polarization at smaller $x \sim 0.02$. In this talk, the inclusive jet $A_{LL}$ and cross-section measurements at $\sqrt{s} =$ 510 GeV, the techniques used in the jet analysis including consideration of underlying event effects, and future perspectives related to jet measurements at STAR will be presented.

Primary author


Jana Bielcikova (Acad. of Sciences of the Czech Rep. (CZ))

Presentation materials