J/psi suppression at SPS and RHIC in the comovers approach

The NA50 collaboration data on the $J/\psi$ suppression are compared with the results obtained in a comovers approach based on the Dual Parton Model (DPM). Predictions for the $J/\psi$ suppression versus the charged multiplicity - measured in the rapidity region of the dimuon trigger - are given for SPS and RHIC energies.Comment: 4 pages, contribution to QM200

Medium-induced multi-photon radiation

We study the spectrum of multi-photon radiation off a fast quark in medium in the BDMPS/ASW approach. We reproduce the medium-induced one-photon radiation spectrum in dipole approximation, and go on to calculate the two-photon radiation in the Moli\`{e}re limit. We find that in this limit the LPM effect holds for medium-induced two-photon ladder emission.Comment: 5 pages, 1 figure. Proceedings of Hot Quarks 2010, La Londe Les Maures, Franc

Measurement of heavy-flavour decay muon production at forward rapidity in pp and Pb-Pb collisions at sqrt(s_NN)=2.76 TeV with the ALICE experiment

The ALICE experiment measured the heavy-flavour production in the semi-muonic decay channel at forward rapidities ($2.5<y<4$) in pp and Pb--Pb collisions at $\sqrt{s_{{NN}}} = 2.76$ TeV. We report on the first results on the $p_{\rm T}$-differential cross-sections in pp collisions as well as on the nuclear modification factors as a function of the transverse momentum and centrality.Comment: 4 pages, 3 figures, Proceedings of parallel talk at the 5th international conference on hard and electromagnetic probes of high-energy nuclear collisions (Hard Probes 2012), Cagliari, Ital

Anomalous suppression of π0\pi^0 production at large transverse momentum in Au + Au and d + Au collisions at sNN=\sqrt{{\bf s}_{\bf NN}} = 200 GeV

We propose a model of suppression of large $p_T$-pions in heavy ion collisions based on the interaction of the large $p_T$ pion with the dense medium created in the collision. The model is practically the same as the one previously introduced to describe $J/\psi$ suppression. Both the $p_T$ and the centrality dependence of the data are reproduced. In deuteron-gold collisions, the effect of the final state interaction with the dense medium turns out to be negligibly small. Here the main features of the data are also reproduced both at mid and at forward rapidities.Comment: 20 pages, latex, 3 postscript figures. Last version, to be published in EJP

Extreme values in SIR epidemic models with two strains and cross-immunity

The paper explores the dynamics of extreme values in an SIR (susceptible → infectious → removed) epidemic model with two strains of a disease. The strains are assumed to be perfectly distinguishable, instantly diagnosed and each strain of the disease confers immunity against the second strain, thus showing total cross-immunity. The aim is to derive the joint probability distribution of the maximum number of individuals simultaneously infected during an outbreak and the time to reach such a maximum number for the first time. Specifically, this distribution is analyzed by distinguishing between a global outbreak and the local outbreaks, which are linked to the extinction of the disease and the extinction of particular strains of the disease, respectively. Based on the mass function of the maximum number of individuals simultaneously infected during the outbreak, we also present an iterative procedure for computing the final size of the epidemic. For illustrative purposes, the twostrain SIR-model with cross-immunity is applied to the study of the spread of antibiotic-sensitive and antibiotic-resistant bacterial strains within a hospital ward

Energy Dependence of the Cronin Effect from Non-Linear QCD Evolution

The non-linear evolution of dense partonic systems has been suggested as one of the novel physics mechanisms relevant to the dynamics of hadron-nucleus and nucleus-nucleus collisions at collider energies. Here we study to what extent the description of Cronin enhancement in the framework of this non-linear evolution is consistent with the recent observation in 200 AGeV d--Au collisions at the Relativistic Heavy Ion Collider. We solve the Balitsky-Kovchegov evolution equation numerically for several initial conditions encoding Cronin enhancement. We find that the properly normalized nuclear gluon distribution is suppressed at all momenta relative to that of a single nucleon. Calculating the resulting spectrum of produced gluons in p-A and A-A collisions, we establish that the nonlinear QCD evolution is unable to generate a Cronin type enhancement, and that it quickly erases any such enhancement which may be present at lower energies.Comment: 4 pages, Latex, 3 eps-figure

Low-x QCD physics from RHIC and HERA to the LHC

We present a summary of the physics of gluon saturation and non-linear QCD evolution at small values of parton momentum fraction $x$ in the proton and nucleus in the context of recent experimental results at HERA and RHIC. The rich physics potential of low-x studies at the LHC, especially in the forward region, is discussed and some benchmark measurements in pp, pA and AA collisions are introduced.Comment: Invited overview talk at the 2nd HERA-LHC Workshop (CERN) and 4th International Conference on Quarks and Nuclear Physics (QNP06, Madrid). 7 pages, 13 figs. To appear in EPJ-