Related papers: Contribution to differential $\pi^0$ and $\gamma_\…
The PHENIX collaboration presents first measurements of low-momentum ($0.4<p_T<3$ GeV/$c$) direct-photon yields from Au$+$Au collisions at $\sqrt{s_{_{NN}}}$=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially…
PHENIX has measured direct photons in p+p and Au+Au collisions at sqrt{s_{NN}}=200 GeV. The p+p measurement is in good agreement with pQCD expectations. The nuclear modification factor in Au+Au is found to be consistent with unity for all…
Two-particle correlations of direct photon triggers with associated hadrons are obtained by isolation method in p+p collisions at \sqrt{s} = 200 GeV in PHENIX at RHIC. The initial momentum of the away-side parton is tightly constrained,…
Results from the first study of isolated-photon + jet correlations in relativistic heavy ion collisions are reported. The analysis uses data from PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair corresponding to an…
It has been established that "hard probes", observables involving high-momentum transfer, provide useful tools for studying the hot, dense medium created in nucleus-nucleus collisions at RHIC. The nuclear modification factor, azimuthal…
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…
Recent studies of high-multiplicity events in small collision systems (proton-proton and proton-lead) have drawn research interest towards the possibility of the formation of partonic medium in such systems. One of the important…
Jet quenching has been one of the most important indicators that ultra-relativistic heavy-ion collisions produce a deconfined state of quarks and gluons, known as the Quark-Gluon Plasma. While the quenching of jets traditionally refers to…
We outline major ideas involved in discussion of color coherence phenomena (CCP) at intermediate energies. We point out that the recent advances in calculating cross sections of hard exclusive processes off light nuclei allow to use the…
We analyze $pA$ interactions at ultra-high energies within the semiclassical approximation for high energy processes accounting for the diffractive processes and a rapid increase with the incident energy of the coherence length. The…
We present new results on the production of charged hadrons and neutral pions in Au+Au and d+Au collisions at sqrt{s_{NN} = 200 GeV, measured within the PHENIX experiment. We observe the opposite centrality dependence when comparing the two…
The hard proton knock-out by the proton from the deuteron at relativistic energies is considered with a focus on the color transparency (CT) effect which influences the initial and final state interactions. The calculations are performed in…
Direct photons are a powerful tool to study the hot and dense matter created in heavy-ion collisions at RHIC, since they are created in the different stages of the collision. Since they do not interact via the strong force, they can travel…
By tuning several experimental observables, such as momentum and reaction plane, the PHENIX experiment has performed a systematic study of high $p_T$ parton energy loss in hot nuclear matter, as well as jet induced medium modifications,…
The measurement of particle correlations and fluctuations has been suggested as a method to search for the existence of a phase transition in relativistic heavy ion collisions. If quark-gluon matter is formed in the collision of…
With the QGP opacity computed perturbatively and with the global entropy constraints imposed by the observed $dN_{ch}/dy\approx1000$, radiative energy loss alone cannot account for the observed suppression of single non-photonic electrons.…
The event-by-event fluctuations of identified particles in ultrarelativistic nucleus-nucleus collisions give information about the state of matter created in these collisions as well as the phase diagram of nuclear matter. In this…
This article is based on my Proceedings for the 47th Course of the International School of Subnuclear Physics on the Most Unexpected at LHC and the Status of High Energy Frontier, Erice, Sicily, Italy, 2009. Results from the PHENIX…
Quarkonia suppression in nucleus-nucleus collisions is a powerful tool to probe the density and temperature of the medium created in heavy ion collisions. Forward rapidity measurements in $p(d)$+Au collisions are essential to understand how…
We address the role of fluctuations in strongly interacting matter during the dense stages of a heavy-ion collision through its electromagnetic emission. Fluctuations of isospin charge are considered in a thermal system at rest as well as…