HBT Effect with fluctuating initial conditions and continuous emission

Submitted by Suelen Oliveira ([email protected]) on 2011-10-10T20:11:06Z No. of bitstreams: 1 HBT EFFECT WITH FLUCTUATING INITIAL.pdf: 176879 bytes, checksum: 612690ca0698da3a4fce958a8b888892 (MD5)Approved for entry into archive by Barbara Milbrath([email protected]) on 2011-10-11T18:17:49Z (GMT) No. of bitstreams: 1 HBT EFFECT WITH FLUCTUATING INITIAL.pdf: 176879 bytes, checksum: 612690ca0698da3a4fce958a8b888892 (MD5)Made available in DSpace on 2011-10-11T18:17:49Z (GMT). No. of bitstreams: 1 HBT EFFECT WITH FLUCTUATING INITIAL.pdf: 176879 bytes, checksum: 612690ca0698da3a4fce958a8b888892 (MD5) Previous issue date: 2005We study effects of the event-by-event fluctuation of the initial conditions and the continuous pion emission during the whole development of the hot and dense matter formed in high-energy collisions on the two-pion interferometry. Important deviations occur, from the standard version of hydrodynamics with smooth initial conditions and a sudden freeze-out on a T = Tfo hypersurface. Comparison with data at RHIC shows that this description can give account of the mT dependence of RL and Rs and significantly improves Ro with respect to the usual version

HBT Effect with fluctuating initial conditions and continuous emission

We study effects of the event-by-event fluctuation of the initial conditions and the continuous pion emission during the whole development of the hot and dense matter formed in high-energy collisions on the two-pion interferometry. Important deviations occur, from the standard version of hydrodynamics with smooth initial conditions and a sudden freeze-out on a T = Tfo hypersurface. Comparison with data at RHIC shows that this description can give account of the mT dependence of RL and Rs and significantly improves Ro with respect to the usual version

Update on the status of hadronic squeezed correlations at RHIC energies

In high-energy heavy-ion collisions, a hot and dense medium is formed, where the hadronic masses may be shifted from their asymptotic values. If this mass modiˇcation occurs, squeezed back-to-back correlations (BBC) of particleÄantiparticle pairs are predicted to appear, both in the fermionic (fBBC) and in the bosonic (bBBC) sectors. Although they have unlimited intensity even for ˇnite-size expanding systems, these hadronic squeezed correlations are very sensitive to their time emission distribution. Here we discuss results in case this time emission is parameterized by a L evy-type distribution, showing that it reduces the signal even more dramatically than a Lorentzian distribution, which already reduces the intensity of the effect by orders of magnitude, as compared to the sudden emission. However, we show that the signal could still survive if the duration of the process is short, and if the effect is searched for lighter mesons, such as kaons. We compare some of our results to recent PHENIX preliminary data on squeezed correlations of K+K − pairs

Particle abundances and spectra in the hydrodynamical description of relativistic nuclear collisions with light projectile

We show that a hydrodynamical model with continuous particle emission instead of sudden freeze out may explain both the observed strange particle and pion abundances and transverse mass spectra for light projectile at SPS energy. We found that the observed enhancement of pion production corresponds, within the context of continuous emission, to the maximal entropy production

A study of <V2> with NeXSPheRIO

Elliptic flow at RHIC is computed event by event with NeXSPheRIO. Reasonable agreement with experimental data on v2(h) and v2(pt) is obtained. Various effects are studied as well: equation of state (with or without critical point), emission mechanism (Cooper-Frye prescription or continuous emission), type of the initial conditions (average or fluctuating initial conditions)

Effect of Event-by-Event Fluctuations on Hydrodynamical Evaluation of Elliptical Flow

Elliptic flow at RHIC is computed event-by-event with NeXSPheRIO. We show that when symmetry of the particle distribution in relation to the reaction plane is assumed, there is a disagreement between the true and reconstructed elliptic flows. We suggest a possible way to take into account the asymmetry and get good agreement between these elliptic flows

pT Distribution of Hyperons in 200A GeV Au-Au in Smoothed Particle Hydrodynamics

The transverse momentum distributions of hadrons in 200GeV Au-Au collisions at RHIC are calculated using the smoothed particle hydrodynamics code SPheRIO. They are compared with data from STAR and PHOBOS Collaborations. By employing an equation of state which explicitly incorporates the strangeness conservation and introducing strangeness chemical potential into the code, the transverse spectra give a reasonable description of experimental data, except the multiplicities of hyperons

Comparison between classification using impact parameter and using number of participants in relativistic nuclear collisions

Using the hydrodynamical code NeXSPheRIO, we compare predictions as usually done in hydrodynamics, using centrality windows defined through the impact parameter, and as obtainable experimentally, using windows in participant number

Effect of chemical freeze-out on identified particle spectra at 200A GeV Au-Au collisions at RHIC using SPheRIO

We investigate the effect of chemical freeze-out on identified particle spectra at 200AGeV Au-Au Collisions at RHIC, by utilizing a full three-dimensional hydrodynamical calculation. The hydrodynamical code SPheRIO we employed is based on the smoothed particle hydrodynamic algorithm. In order to describe the spectra of strange hadrons, the code has been further improved by explicitly incorporating the strangeness conservation and a chemical freeze-out mechanism. In our model, strange hadrons such as , , and undergo the chemical freeze-out immediately after the hadronization, and their multiplicitiesare fixed thereafter. At a lower temperature the thermal freeze-out takes place for all the particles. It is shown that the present model provides a reasonably good description for the spectra of identified particles, in particular, considerable improvement is observed for those of strange hadrons