arXiv subjects

Krzysztof Wozniak

Publications and source records attributed to Krzysztof Wozniak.

4 recordsLinked to original sources

arXiv2010

Long range phenomena in heavy ion collisions observed by the PHOBOS experiment

The PHOBOS experiment at RHIC has measured large samples of Au+Au and Cu+Cu collisions using a detector with uniquely large angular acceptance. These data enable studies of particle production over a very wide pseudorapidity interval which reveal unexpected features. In the analysis of correlations with a high-$p_{_{T}}$ trigger particle ($p_{_{T}}>2.5$ GeV/c) a ridge extending at least 4 units of pseudorapidity was found. The results on forward-backward and two-particle correlations suggest that particles are produced in very large clusters which are wider in pseudorapidity than is expected for isotropic decays. Explanation of these experimental results requires models in which both short-range and long-range correlations are present.

nucl-ex↗

arXiv2009

Forward-backward multiplicity fluctuations in heavy nuclei collisions in the wounded nucleon model

We use the wounded nucleon model to study the forward-backward multiplicity fluctuations measured by the PHOBOS Collaboration in Au+Au collisions at sqrt(s_NN)=200 GeV. The enhancement of forward-backward fluctuations in Au+Au collisions with respect to the elementary p+p interactions is in this model explained by the asymmetric shape of the pseudorapidity density of produced particles from a single wounded nucleon and the fluctuations of the number of wounded nucleons in the colliding nuclei. The wounded nucleon model describes these experimental data better than the HIJING, AMPT or UrQMD models do.

hep-ph↗

arXiv2008

Study of the quark-gluon matter by the PHOBOS experiment

The PHOBOS experiment at the Relativistic Heavy Ion Collider (RHIC) has collected a large dataset of Au+Au, Cu+Cu, d+Au and p+p collisions in the center of mass energy range spanning from 19 GeV/nucleon to 200 GeV/nucleon. The almost full angular coverage of the PHOBOS detector allows the study of particle production over 10 units pseudorapidity. The unique design of the spectrometer enables reconstruction and identification of charged particles down to very low transverse momenta. In this paper properties of the strongly interacting Quark-Gluon Plasma (sQGP) created in the nucleus-nucleus collisions at the highest energy available in laboratory are discussed. Results from the PHOBOS experiment on jet suppression, very low pt particles production and elliptic flow are shown. In more details are presented the most recent studies of the correlations of charged particles with respect to a high-pt trigger particle, elliptic flow fluctuations and two particle correlations.

nucl-ex↗

arXiv2007

Multiplicity Fluctuations in Au+Au Collisions at RHIC

In the PHOBOS experiment, charged particles are measured in almost the full solid angle. This enables the study of fluctuations and correlations in the particle production over a very wide kinematic range. In this paper, we show results of a direct search for fluctuations identified by an unusual shape of the pseudorapidity distribution. In addition, we use analysis of correlations of the multiplicity in similar pseudorapidity bins, placed symmetrically in the forward and backward hemispheres, to test the hypothesis of production of particles in clusters.

nucl-ex↗