Statistical hadronization phenomenology in K/πK/\pi fluctuations at ultra-relativistic energies

We discuss the information that can be obtained from an analysis of fluctuations in heavy ion collisions within the context of the statistical model of particle production. We then examine the recently published experimental data on ratio fluctuations, and use it to obtain constraints on the statistical properties (physically relevant ensemble, degree of chemical equilibration, scaling across energies and system sizes) and freeze-out dynamics (amount of reinteraction between chemical and thermal freeze-out) of the system.Comment: Proceedings, SQM2009. Fig. 4, the main results figure, was wrong due to editing mistake, now correcte

Phenomenology of Strangeness enhancement in heavy ion collisions

We give an overview of the phenomenology of strangeness enhancement in heavy ion collisions, within the paradigm of the statistical model of particle production. We argue that, while strangeness enhancement data is suggestive of a phase transition, the mechanism triggering enhancement is still elusive. We study the feasibility to constrain this mechanism by determining the scaling variable of strangeness enhancement. We further argue that to test the applicability of the statistical model generally, and to confirm our interpretation of the statistical physics responsible for strangeness enhancement, the scaling of strange particle fluctuations ($K/\pi$ and other particles) w.r.t. yields has to be explored.Comment: Plenary talk, SQM2008, Beijing, China Minor stylistic revisions, discussion on scaling of enhancement added, references update

Elliptic flow fluctuations and correlations in Au+Au collisions at sNN=200\sqrt{s_{NN}}=200 GeV

In this talk, we report an analysis of elliptic flow ($v_2$), non-flow ($\delta_{2}$), and $v_2$ fluctuations ($\sigma_{v_{2}}$) for the STAR collaboration at middle rapidity in $\sqrt{s_{_{NN}}}=200$ GeV Au+Au collisions. We compare the results to models of the fluctuations in the initial eccentricity of the overlap zone.Comment: Quark Matter 2008 proceedings, 4 pages, 4 figure

Multiplicity dependence of K*(892)0 and ϕ(1020) production in pp collisions at s

The striking similarities that have been observed between high-multiplicity proton-proton (pp) collisions and heavy-ion collisions can be explored through multiplicity-differential measurements of identified hadrons in pp collisions. With these measurements, it is possible to study mechanisms such as collective flow that determine the shapes of hadron transverse momentum (pT) spectra, to search for possible modifications of the yields of short-lived hadronic resonances due to scattering effects in an extended hadron-gas phase, and to investigate different explanations provided by phenomenological models for enhancement of strangeness production with increasing multiplicity. In this paper, these topics are addressed through measurements of the K⁎(892)0 and ϕ(1020) mesons at midrapidity in pp collisions at s= 13 TeV as a function of the charged-particle multiplicity. The results include the pT spectra, pT-integrated yields, mean transverse momenta, and the ratios of the yields of these resonances to those of longer-lived hadrons. Comparisons with results from other collision systems and energies, as well as predictions from phenomenological models, are also discussed