Medium Modification of the Jet Properties

In the case that a dense medium is created in a heavy ions collision, high-E_t jets are expected to be broadened by medium-modified gluon emission. This broadening is directly related, through geometry, to the energy loss measured in inclusive high-p_t particle suppression. We present here the modifications of jet observables due to the presence of a medium for the case of azimuthal jet energy distributions and k_t-differential multiplicities inside the jets.Comment: 4 pages, 3 postscript figures. Proceedings for Quark Matter 200

Jets in heavy ion collisions

High energetic particles traversing a dense medium lose a sizable part of their energy in form of gluon radiation. As a result, the rate of high-$p_t$ particles is expected to be suppressed in heavy ion collisions with respect to the proton case. Recent experimental data from RHIC strongly support this scenario. This allows to study the properties of the medium by the amount of jet quenching it produces. The angular dependence of the radiation is modified in the medium in a characteristic way. This provides another tool to study the medium properties in a more differential measurement.Comment: 4 pages, 3 postscript figures. Contributed to 38th Rencontres de Moriond on QCD and Hadronic Interactions, Les Arcs, France, 22-29 Mar 200

Theory summary. Hard Probes 2012

I provide a summary of the theoretical talks in Hard Probes 2012 together with some personal thoughts about the present and the future of the field.Comment: 8 pages. Proceedings of the conference Hard Probes 2012 - Sardinia - Italy - May 27 -June 1 2012 --- Comments welcom

Neutrino-nucleus DIS data and their consistency with nuclear PDFs

In this talk, we discuss the compatibility of different deeply inelastic neutrino-nucleus data sets and the universal nuclear PDFs. This is an issue that has lately been investigated by different groups but the conclusions have been surprisingly contradictory. While some studies have found a good overall agreement between the nuclear PDFs and the neutrino data, others have claimed for an incompatibility. Here, we demonstrate that the independent neutrino data sets from NuTeV, CHORUS and CDHSW collaborations differ in the absolute overall normalization and that it is not possible to accurately reproduce all the data simultaneously with a single set of PDFs. Our strategy to overcome this difficulty and allow a consistent use of all neutrino data in global PDF analyses is to normalize the data by the integrated cross-sections thereby cancelling possible inaccuracies in the absolute normalization. Indeed, this brings all data to a surprisingly good mutual agreement underscoring the x-dependence of the nuclear modifications in a model-independent way. The consistency of these data with the present nuclear PDFs is verified by introducing a method to test the effect of a new data set in an existing global fit that performed a Hessian error analysis.Comment: A transcription of the talk given in XXI International Workshop on Deep-Inelastic Scattering and Related Subjects, Marseilles, Franc

Gluon distributions in nuclei at small x: guidance from different models

Different approaches to gluon shadowing at small x are reviewed. Some available results relevant for RHIC and LHC are compared.Comment: 6 pages, LaTeX2e, uses enclosed cernrep.cls, one eps figure enclosed using graphicx, contribution to the Yellow Report on Hard Probes in Heavy Ion Collisions at the LH

Baryon and Antibaryon production at RHIC energies in the Dual Parton Model

We compute the mid-rapidity densities of pions, kaons, baryons and antibaryons in $Au$--$Au$ collisions at $\sqrt{s}$ = 130 GeV in the Dual Parton Model supplemented with final state interactions, and we present a comparison with available data.Comment: 4 pages, 2 figures. Talk given at XXXVII Rencontres de Moriond, Les Arcs, France, March 200