Related papers: Highlights from PHENIX-I: Initial State and Early …
Previous results indicated that high $p_T$ particle suppression in Au+Au interactions is a final state effect, since R$_{dA}$ ratios were compatible with unity, albeit within large experimental errors. It is important to test this…
The first evidence of jet quenching was observed at RHIC via suppression of single high $p_T$ hadron $R_{AA}$ and the disappearance of the away-side jet peak in two-particle correlations. Since then, hadron $R_{AA}$ and two-particle…
High pT \pi^0 and \eta, as well as jets are measured using high statistics d+Au collision data collected in RHIC Year-2008 run. Both R_{dA} and R_{cp} for three observables are found to be very consistent each other within quoted systematic…
Hard-scattering in p-p collisions was discovered in 1972 at the CERN-ISR, the first hadron collider. Techniques were developed and several hard-processes were discovered which form the basis for many of the measurements made in p-p and…
We present measurements of J/psi yields in d+Au collisions at sqrt(s_NN) = 200 GeV recorded by the PHENIX experiment and compare with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large…
PHENIX has measured $\Upsilon$ production in p+p, d+Au and Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV. A baseline cross-section measurement has been made in p+p collisions. Preliminary studies of d+Au collisions found no suppression in the…
Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of…
The PHENIX collaboration has measured low momentum direct photon radiation in Au+Au collisions at 200 GeV, 62.4 GeV and 39 GeV, in Cu+Cu at 200 GeV as well as in p+p, p+Au and d+Au at $\sqrt{s_{NN}} =$ 200 GeV. In these measurements PHENIX…
Direct photons, being colorless objects, provide an unmodified control particle that can be used in conjunction with jets to probe the quark-gluon plasma. To leading order the direct photon momentum balances the momentum of opposing jets…
Measurement of heavy quark production is one of the tools used to investigate the matter produced in extremely hot and dense conditions in heavy ion collisions at RHIC. The PHENIX experiment has measured mid-rapidity transverse momentum…
Recently, there is growing evidence that a new state of matter is formed in sqrt(s_NN)= 200 GeV Au+Au collisions at RHIC: a strongly coupled Quark Gluon Plasma of partonic degrees of freedom which develops a collective motion. Dilepton…
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…
We investigate the possibility of selecting heavy ion collision events with certain features in the initial state ("event engineering"). Anisotropic flow measurements in heavy ion reactions have confirmed the almost ideal fluid dynamical…
PHENIX has measured $J/\psi$ production at backward, central and forward rapidities both in p+p and d+Au collisions at $\sqrt{s_{NN}}=200$ GeV during the third run of the RHIC collider. From the p+p collisions, we measure the total J/$\psi$…
PHENIX has measured high transverse momentum (pT) identified hadrons in different collision species and energies in the last five RHIC runs. The systematic study of the high pT hadron production provides an idea on interaction of hard…
Recent results on identified hadrons from the PHENIX experiment in Au+Au collisions at mid-rapidity at $\sqrt{s_{NN}}$ = 200 GeV are presented. The centrality dependence of transverse momentum distributions and particle ratios for…
The measurement of phi mesons provides a unique and complementary method for exploring properties of the hot and dense medium created in the relativistic heavy ion collisions. It has a relatively small hadronic interaction cross section and…
Direct photon yield measured in p+p and d+Au collisions at \sqrt{s} = 200 GeV with the PHENIX experiment is presented and compared to pQCD predictions. In the case of p+p collisions both the inclusive and isolated direct photon production…
Observations from high-multiplicity proton-lead ($p$-Pb) collisions indicate that small systems may exhibit collective behavior in both heavy and light hadrons. This work investigates the roles of initial- and final-state interactions in…
The PHENIX Experiment at the Relativistic Heavy Ion Collider has made measurements of event-by-event fluctuations in the charged particle multiplicity as a function of collision energy, centrality, collision species, and transverse momentum…