Heavy-ion results from the LHC

A summary of the experimental results from Pb-Pb collisions at the LHC is given.Comment: 8 pages. Prepared for the proceedings of XXXI Physics in Collision, Vancouver, BC Canada, August 28 - September 1, 201

Results from the commissioning of the ALICE Inner Tracking System with cosmics

The Inner Tracking System (ITS) is the detector of the ALICE central barrel located closest to the beam axis and it is therefore a key detector for tracking and vertexing performance. Here, the main results from the ITS commissioning with atmospheric muons in 2008 are presented, focusing in particular on the detector operation and calibration and on the methods developed for the alignment of the ITS detectors using reconstructed tracks.Comment: 4 pages, 1 figure with 3 panels (=3 separate eps files) To appear in the conference proceedings for Quark Matter 2009, March 30 - April 4, Knoxville, Tennesse

ALICE Overview

A general overview of the results obtained by the ALICE experiment from the analysis of the \PbPb data sample collected at the end of 2010 during the first heavy-ion run at the LHC is presented.Comment: 8 pages, proceedings of Strangeness in Quark Matter 2011 conferenc

Open heavy flavour reconstruction in the ALICE central barrel

The ALICE experiment will be able to detect open charm and beauty hadrons in proton-proton and heavy ion collisions in the new energy regime of the CERN Large Hadron Collider (LHC). Heavy flavours are a powerful tool to investigate the medium created in high energy nucleus--nucleus interactions because they are produced in the hard scatterings occurring at early times and, thanks to their long lifetime on the collision timescale, they probe all the stages of the system evolution. The detectors of the ALICE central barrel ($-0.9 < \eta < 0.9$) will allow to track charged particles down to low transverse momentum ($\approx$ 100 MeV/$c$) and will provide hadron and electron identification as well as an accurate measurement of the positions of primary and secondary vertices. It will therefore be possible to measure the production of open heavy flavours in the central rapidity region down to low transverse momentum, exploiting the semi-electronic and the hadronic decay channels. Here we present a general overview of the ALICE perspectives for heavy flavour physics and some examples from the open charm and beauty analyses which have been developed and tested on detailed simulations of the experimental apparatus.Comment: ICHEP0

Heavy flavours in heavy-ion collisions: quenching, flow and correlations

We present results for the quenching, elliptic flow and azimuthal correlations of heavy flavour particles in high-energy nucleus-nucleus collisions obtained through the POWLANG transport setup, developed in the past to study the propagation of heavy quarks in the Quark-Gluon Plasma and here extended to include a modeling of their hadronization in the presence of a medium. Hadronization is described as occurring via the fragmentation of strings with endpoints given by the heavy (anti-)quark Q(Qbar) and a thermal parton qbar(q) from the medium. The flow of the light quarks is shown to affect significantly the R_AA and v_2 of the final D mesons, leading to a better agreement with the experimental data. The approach allows also predictions for the angular correlation between heavy-flavour hadrons (or their decay electrons) and the charged particles produced in the fragmentation of the heavy-quark strings

Early physics with ALICE

The ALICE experiment at the CERN Large Hadron Collider started its p-p data taking at the end of 2009. The availability of the first low luminosity collisions at √s = 900 GeV and √s = 2.36TeV allowed to improve and extend the calibration and alignment procedures, started with cosmic rays in 2008. Together with the final commissioning of the detector with real data, the collected data sample of p-p collisions is presently being used to carry out the early physics studies, aimed at assessing the global characteristics of the interaction. In particular, results on the pseudorapidity density of primary charged particle in the central region are discussed here. They were obtained using the two innermost Silicon Pixel layers of the Inner Tracking System, which provided both the primary vertex position and the charged multiplicity, by matching the reconstructed points on the two layers