Direct photon measurement in Au+Au collisions at sNN\sqrt{s_{NN}}=200GeV a t RHIC

Direct photon production in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV has been measured. The result is compared to several theoretical calculations, and found that it is not inconsistent with ones including thermal radiation from QGP or jet-photon conversion process on top of a NLO pQCD expectation. The direct photon contribution in dilepton measurement is also evaluated.Comment: 3 pages, 2 figures. Contributed talk at PANIC '05 conference, Santa Fe, NM, Oct24-28, 200

System size and energy dependence of high pT hadron production measured with PHENIX experiment at RHIC

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 scattered partons and the matter created in relativistic heavy ion collision. The eta/pi0 ratio is measured in Au+Au collisions, which gives a hint on the system thermalization and particle production. A future measurement of hadron and photon measurement is discussed.Comment: 6 pages, 9 figures, Contributions for Quark Matter 2006 poster ssessio

Photon production in sNN\sqrt{s_{NN}}=200 GeV Au+Au collisions measured by the PHENIX experiment at RHIC

Direct photon production in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV has been measured in the $p_T$ range of 1$<$$p_T$$<$5 GeV/$c$. The yield as acfunction of centrality is in agreement with published data of the RHIC 2002 run, and with results from a new method that explores very low mass dileptons. The result is compared to several theoretical calculations, and it is found that the measurement is not inconsistent with calculations including thermal photon contributions.Comment: 6 pages, 7 figures. Poster proceedings for Quark Matter Conference 2005, held in Budapest, Hungary, Aug 4-9, 2005. To be appeared in Acta Physica Hungarica, Nuclear Science, Heavy Ion Physics A. Revised along Referee's comment

Profiling hot and dense nuclear medium with high transverse momentum hadrons produced in d+Au and Au+Au collisions by the PHENIX experiment at RHIC

PHENIX measurements of high transverse momentum ($p_T$) identified hadrons in $d$+Au and Au+Au collisions are presented. The nuclear modification factors ($R_{d{\rm A}}$ and $R_{\rm AA}$) for $\pi^0$ and $\eta$ are found to be very consistent in both collision systems, respectively. Using large amount of $p+p$ and Au+Au datasets, the fractional momentum loss ($S_{\rm loss}$) and the path-length dependent yield of $\pi^0$ in Au+Au collisions are obtained. The hadron spectra in the most central $d$+Au and the most peripheral Au+Au collisions are studied. The spectra shapes are found to be similar in both systems, but the yield is suppressed in the most peripheral Au+Au collisions.Comment: 4 pages, 5 figures, talk presented at the International Nuclear Physics Conference 2013, held in Florence, Italy, on June 2 - 7, 201