Open Heavy Flavor Production in p+p, d+Au and Au+Au Collisions at (s)=200\sqrt(s)= 200 GeV

PHENIX results for open charm production from semi-lepton decay in p+p, d+Au and Au+Au collisions in a wide rapidity ranges at $\sqrt(s)= 200$ GeV are presented. Keywords: Relativistic Heavy-ion Collision, Open Charm production, Nuclear Medium Effect PACS: 25.75.-q, 25.75 Dw, 13.20.G

Comment on 'Comparison of strangeness production between A + A and p + p reactions from 2 to 160 A GeV', by J. C. Dunlop and C. A. Ogilvie

A recent paper on energy dependence of strangeness production in A+A and p+p interactions written by Dunlop and Ogilvie (Phys. ReV. C61 031901(R) (2000) indicates that there is a significant misunderstanding about the concept of strangeness enhancement and its role as a signal of Quark Gluon Plasma creation. In this comment we will try to clarify some essential points. 25.75.Dw, 13.85.Ni, 21.65.+

Creation of strange matter at low initial m/T

We demonstrate that the creation of strange matter is conceivable in the midrapidity region of heavy ion collisions at Brookhaven RHIC and CERN LHC. A finite net-baryon density, abundant (anti)strangeness production, as well as strong net-baryon and net-strangeness fluctuations, provide suitable initial conditions for the formation of strangelets or metastable exotic multistrange ( baryonic) objects. Even at very high initial entropy per baryon SyAinit ¯ 500 and low initial baryon numbers of Ainit B ¯ 30 a quark-gluon-plasma droplet can immediately charge up with strangeness and accumulate net-baryon number. PACS numbers: 25.75.Dw, 12.38.Mh, 24.85.

Hadron production in relativistic nuclear collisions : Thermal hadron source or hadronizing quark-gluon plasma?

Measured hadron yields from relativistic nuclear collisions can be equally well understood in two physically distinct models, namely a static thermal hadronic source vs. a time-dependent, nonequilibrium hadronization o a quark-gluon plasma droplet. Due to the time-dependent particle evapora- tion o the hadronic surface in the latter approach the hadron ratios change (by factors of <H 5) in time. Final particle yields reflect time averages over the actual thermodynamic properties of the system at a certain stage of the evolution. Calculated hadron, strangelet and (anti-)cluster yields as well as freeze-out times are presented for di erent systems. Due to strangeness distillation the system moves rapidly out of the T, µq plane into the µs-sector. Classif.: 25.75.Dw, 12.38.Mh, 24.85.+

πωρ\pi\omega\rho vertex in nuclear matter

Medium modifications of the $\pi \omega \rho$ vertex are analyzed in context of the $\omega \to \pi^0 \gamma^\ast$ and $\rho \to \pi \gamma^\ast$ decays in nuclear matter. A relativistic hadronic model with mesons, nucleons, and $\Delta(1232)$ isobars is applied. A substantial increase of the widths for the decays $\omega \to \pi^0 \gamma^\ast$ and $\rho \to \pi \gamma^\ast$ is found for photon virtualities in the range $0.3-0.6$GeV. This enhancement has a direct importance for the description of dilepton yields from dalitz decays in relativistic heavy-ion collisions.Comment: 3 pages, 2 Postscript figures, uses appolb.cls (included). Presented at 7th International Workshop on Meson Production, Properties and Interaction, Krak\'ow, Poland, 24-28 May 200

PHENIX results on Bose-Einstein correlation functions

Measurement of Bose-Einstein or HBT correlations of identified charged particles provide insight into the space-time structure of particle emitting sources in heavy-ion collisions. In this paper we present the latest results from the RHIC PHENIX experiment on such measurements.Comment: 4 pages, 3 figures, WPCF-2015 conference proceeding

Non-extensivity Parameter of Thermodynamical Model of Hadronic Interactions at LHC energies

The LHC measurements above SPS and Tevatron energies give the opportunity to test predictions of non-extensive thermodynamical picture of hadronic interaction to examine measured transverse momenta distributions for new interaction energy range. We determined Tsallis model non-extensivity parameter for the hadronization process before short-lived particles decayed and distort the initial p_t distribution. We have shown that it follows exactly smooth rise determined at lower energies below present LHC record. The shape of the q parameter energy dependence is consistent with expectations and the evidence of the asymptotic limit may be seen.Comment: 2 pages, 2 figure