Related papers: Parton Rescatterings in Large-x Nuclear Suppressio…
Experimental results related to charged particle and $\pi^{0}$ suppression obtained at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven for Au-Au (Cu-Cu) collisions and at the Large Hadron Collider (LHC) at CERN for Pb-Pb (Xe-Xe)…
High $p_{\rm T}$ hadrons in the small systems of $d/^3$He+Au and $p$+Al/Au collisions have been measured at the midrapidity ($|\eta|<0.35$) as well as at the forward and backward rapidities ($1.2<|\eta|<2.4$) at $\sqrt{s_{NN}}$=200GeV. A…
Transverse momentum spectra of charged hadrons with p_T < 8 GeV/c and neutral pions with p_T < 10 GeV/c have been measured at mid-rapidity by the PHENIX experiment at RHIC in d+Au collisions at sqrt(s_NN) = 200 GeV. The measured yields are…
Problem of high PT suppression in RHIC data is generally associated to jet quenching in a dense medium. We recently proposed a new approach to high energy nuclear scattering, which treats the initial stage of heavy ion collisions in a…
The interplay of nuclear effects on the p_T > 2 GeV inclusive hadron spectra in d+Au and Au+Au reactions at root(s) = 17, 200, 5500 GeV is compared to leading order perturbative QCD calculations for elementary p+p (p-bar+p) collisions. The…
We consider the influence of parton saturation in the Color Glass Condensate on the back-to-back azimuthal correlations of high $p_T$ hadrons in $pA$ (or $dA$) collisions. When both near--side and away--side hadrons are detected at…
We study the dependence of parton energy loss (quenching) on rapidity in ultra-relativistic nuclear collisions at RHIC. This can provides invaluable information on the density of the medium, which should be more dilute going away from…
Several puzzles about the data at high $p_T$ in heavy-ion collisions are listed. The resolution of them all is given in the framework of parton recombination. More specifically, it is the recombination of the soft and semi-hard shower…
We perform a complete theoretical analysis of the azimuthal angular correlation of two-hadron productions in the forward $dAu$ collisions at RHIC in the saturation formalism, and obtain a very good agreement with the experimental data. It…
Multiple hard interactions of partons in the same p+p(\bar p) collision are a useful concept in the description of these collisions at collider energies. In particular, they play a crucial role for the understanding of the background (the…
Multiple parton interactions in relativistic heavy ion reactions result in transverse momentum diffusion and medium induced non-Abelian energy loss of the hard probes traversing cold and hot nuclear matter. A systematic study of the…
Highlights of recent results from the STAR collaboration focusing on hard probes of the initial and final state are presented. New results at forward rapidities in d+Au collisions at low $x$ are utilized to study the possible onset of…
High-pT hadrons produced in hard collisions and detected inclusively bear peculiar features: (i) they originate from jets whose initial virtuality and energy are of the same order; (ii) such jets are rare and have a very biased energy…
High-pT particle production is suppressed in heavy ion collisions due to parton energy loss in dense QCD matter. Here we present a systematic comparison of two different theoretical approximations to parton energy loss calculations: the…
We report the observation at the Relativistic Heavy Ion Collider (RHIC) of suppression of back-to-back correlations in the direct photon+jet channel in Au+Au relative to p+p collisions. Two-particle correlations of direct photon triggers…
We explore how nuclear modifications to the nucleon parton distributions affect production of high transverse momentum hadrons in deuteron-nucleus collisions. We calculate the charged hadron spectra to leading order using standard…
Heavy quarkonia are observed to be suppressed in relativistic heavy ion collisions relative to their production in p+p collisions scaled by the number of binary collisions. In order to determine if this suppression is related to color…
Great interest has attached to recent Au+Au, E = 200 A GeV measurements at RHIC, obtained with the PHENIX, STAR, PHOBOS and BRAHMS detectors. For central collisions and vanishing pseudo-rapidity all experiments indicate a considerable…
We show that the recently observed suppression of the yield ratio of deuteron to proton and of helium-3 to proton in p+p collisions compared to those in p+Pb or Pb+Pb collisions by the ALICE Collaboration at the Large Hadron Collider (LHC)…
Fully reconstructed jets and direct photon-tagged jet fragments significantly reduce energy-loss bias, the bias toward mostly measuring particles from partons which suffer little energy loss. In d+Au collisions, one accesses the physics at…