Heavy-Flavor Collectivity - Light-Flavor Thermalization at RHIC

Flow measurements of multi-strange baryons from Au + Au collisions at RHIC energies demonstrate that collectivity develops before hadronization, among partons. To pin down the partonic EOS of matter produced at RHIC, the status of thermalization in such collisions has to be addressed. We propose to measure collective flow of heavy-flavor quarks, e.g. charm quarks, as an indicator of thermalization of light flavors ($u,d,s$). The completion of the time of flight barrel and the proposed upgrade with a $\mu$Vertex detector for heavy-flavor identification in STAR are well suited for achieving these goals.Comment: proceedings of the ISMD 2005 conference, Kromeriz, Czech Republic; 6 pages, 4 figure

The three-dimensional BF Model with Cosmological Term in the Axial Gauge

We quantize the three-dimensional $BF$-model using axial gauge conditions. Exploiting the rich symmetry-structure of the model we show that the Green-functions correspond to tree graphs and can be obtained as the unique solution of the Ward-Identities. Furthermore, we will show that the theory can be uniquely determined by symmetry considerations without the need of an action principle.Comment: one reference added, transmission errors correcte

Remarks on Topological SUSY in sixdimensional TQFTs

We establish the existence of the topological vector supersymmetry in the six dimensional topological field theory for two-form fields introduced by Baulieu and West. We investigate the relation of these symmetries to the twist operation for the (2,0) supersymmetry and comment on their resemblance to the analogous symmetries in topological Yang-Mills theory.Comment: 12 pages, to be published in JHEP 11(1999)03

Study of Cronin effect and nuclear modification of strange particles in d-Au and Au-Au collisions at 200 GeV in PHENIX

Effects of strangeness on nuclear modification in d-Au and Au-Au collisions at 200 GeV are studied, in order to quantify the effects of quark content and mass. Measurements of ratios of the yields in central collisions to the yields in peripheral collisions are performed for lambda baryon and phi meson. Found results show little dependence of particle suppression or enhancement on mass and strange content, but rather prominent difference in nuclear modification between mesons and baryons.Comment: 4 pages, 4 figures, proceedings of the Seventeenth International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2004

Heavy-quark azimuthal momentum correlations as a sensitive probe of thermalization

In high-energy nuclear collisions the degree of thermalization at the partonic level is a key issue. Due to their large mass, heavy quarks and their possible participation in the collective flow of the QCD-medium constitute a powerful probe for thermalization. We present studies with PYTHIA for p+p collisions at the top LHC energy of $\sqrt{s}$ = 14 TeV applying the two-particle transverse momentum correlator $$ to pairs of heavy-quark hadrons and their semi-leptonic decay products as a function of their relative azimuth. Modifications or even the complete absence of initially existing correlations in Pb+Pb collisions might indicate thermalization at the partonic level.Comment: 7 pages, 5 figs.; accepted for publication in Nucl. Phys.