Charm and beauty of the Large Hadron Collider

With the acceleration of lead nuclei in the LHC, heavy-ion physics will enter a new energy domain. One of the main novelties introduced by the 30-fold energy-jump from RHIC to the LHC is the abundant heavy-quark production. After discussing a few examples of physics issues that can be addressed using heavy quarks, we present a selection of results on the expected experimental capability of ALICE, the dedicated heavy-ion experiment at the LHC, in the open-heavy-flavour sector.Comment: 10 pages, 5 figures. Invited talk at Strangeness in Quark Matter (SQM) 2004, Cape Town, South Africa, 15-20 September 2004. Submitted to J. Phys.

Correlations of Heavy Quarks Produced at Large Hadron Collider

We study the correlations of heavy quarks produced in relativistic heavy ion collisions and find them to be quite sensitive to the effects of the medium and the production mechanisms. In order to put this on a quantitative footing, as a first step, we analyze the azimuthal, transverse momentum, and rapidity correlations of heavy quark-anti quark ($Q\overline{Q}$) pairs in $pp$ collisions at $\cal{O}$($\alpha_{s}^{3}$). This sets the stage for the identification and study of medium modification of similar correlations in relativistic collision of heavy nuclei at the Large Hadron Collider. Next we study the additional production of charm quarks in heavy ion collisions due to multiple scatterings, {\it viz.}, jet-jet collisions, jet-thermal collisions, and thermal interactions. We find that these give rise to azimuthal correlations which are quite different from those arising from prompt initial production at leading order and at next to leading order.Comment: 26 pages, 15 figures. Three new figures added, comparison to experimental data included, abstract and discussion expande

Heavy Flavor Probes of Quark Matter

A brief survey of the role of heavy flavors as a probe of the state of matter produced by high energy heavy ion collisions is presented. Specific examples include energy loss, initial state gluon saturation, thermalization and flow. The formation of quarkonium bound states from interactions in which multiple heavy quark-antiquark pairs are initially produced is examined in general. Results from statistical hadronization and kinetic models are summarized. New predictions from the kinetic model for J/Psi at RHIC are presented.Comment: Based on invited plenary talk at Strange Quark Matter 2004, Cape Town, South Africa, September 15-20, 2004, references completed, published in J. Phys. G: Nucl. Part. Phys. 31 (2005) S641-S64

Measurement of the nuclear modification factor of electrons from heavy-flavour decays at mid-rapidity in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV with ALICE

We present results on inclusive electrons for 1.5 $< p_{\rm T} <$ 6 GeV/$c$ in {Pb-Pb} collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV measured with ALICE at the LHC and compare these to a cocktail of background electron sources. The excess of electrons beyond the cocktail at high momenta ({$p_{\rm T} >$ 3.5 GeV/$c$}) is attributed to electrons from heavy-flavour decays. The corresponding nuclear modification factor indicates heavy-flavour suppression by a factor of 1.5-4.Comment: 4 pages; 4 figures; QM 2011 proceeding

Measuring beauty production in Pb-Pb collisions at the LHC via single electrons in ALICE

We present the expected ALICE performance for the measurement of the p_t-differential cross section of electrons from beauty decays in central Pb-Pb collisions at the LHC.Comment: 4 pages, 2 figures, proceeding of poster presentation at "Quark Matter 2005

D meson nuclear modification factors in Pb-Pb collisions at {\surd}sNN = 2.76 TeV, measured with the ALICE detector

The ALICE experiment has measured the D meson production in pp and Pb-Pb collisions at the LHC at {\surd}s = 7 and 2.76 TeV and {\surd}sNN = 2.76 TeV respectively, via the exclusive reconstruction of hadronic decay channels. The analyses of the D0{\to}K-pi+ and D+{\to}K-pi+pi+ channels will be described and the preliminary results for the D0 and D+ nuclear modification factor will be presented.Comment: Proceedings of Quark Matter 2011 conference. 4 pages, 4 figures. The slides of the talk can be found at the link: http://indico.cern.ch/materialDisplay.py?contribId=591&sessionId=53&materialId=slides&confId=3024

Heavy-flavour production in Pb-Pb collisions at the LHC, measured with the ALICE detector

We present the first results from the ALICE experiment on the nuclear modification factors for heavy-flavour hadron production in Pb-Pb collisions at sqrt{s_NN}=2.76 TeV. Using proton-proton and lead-lead collision samples at sqrt{s}=7 TeV and sqrt{s_NN}=2.76 TeV, respectively, nuclear modification factors R_AA(pt) were measured for D mesons at central rapidity (via displaced decay vertex reconstruction), and for electrons and muons, at central and forward rapidity, respectively.Comment: 8 pages, 5 figures, plenary talk at Quark Matter 2011, Annecy, Franc

Physicochemical parameters and antibiotics residuals in Algerian honey

The aim of the present study was to evaluate the quality of 36 samples of different honey type supplied by local producers from Algeria in order to verify its compliance with the standards of Codex Alimentarius and  European Union (EU). For that, five physicochemical parameters were  analyzed using the HPLC method: hydroxyl-methyl furfural (HMF), sugars, diastase activity and search of antibiotic contamination with streptomycin and tetracycline. The physicochemical analyses of the Algerian honeys show that 56% of samples correspond to Codex standards and 44% not in  conformity with the standards required by the Codex Alimentarius and EU, because part of the samples had one or more defects. The percentage not in conformity was due to the high rates of hydroxyl-methyl furfural, sucroseand also to the low enzyme level. Analysis performed by the laboratory to detect residues of tetracycline and streptomycin in honey have revealed insignificant traces of oxytetracycline in two samples of honey (0.03 ppb). From the present study, it is observed that the Algerian honey samples is not completely in agreement with the requirements of international honey standards which could be caused by inappropriate actions during processing and storage steps.Key words: Honey quality, sugar, diastase activity, hydroxymethylfurfural, antibiotic residues

Genitori migranti e figli con disabilit\ue0 Le rappresentazioni dei professionisti e le percezioni delle famiglie

Il contributo si occupa di un tema poco indagato nel panorama delle ricerche italiane ed europee, quello della disabilit\ue0 e della migrazione; su questo tema \u201cintrecciato\u201d la ricerca si pone come una delle prime a livello europeo. Dai primi dati della ricerca e da una prima analisi del materiale qualitativo e quantitativo, emerge: da parte degli insegnanti, la difficolt\ue0 di comunicazione e di coinvolgimento delle famiglie dovuta a rapporti frettolosi (necessit\ue0 di mediatori culturali e di tempo), a fronte di una discreta/buona collaborazione quando vi \ue9 coinvolgimento; da parte dei genitori, l\u2019enorme difficolt\ue0 nella quotidiana accessibilit\ue0 (case inadeguate ecc.); la non curanza di alcune realt\ue0 (questura, servizi, comune ecc.) a informarli correttamente e tempestivamente sui loro diritti; la totale assenza di qualunque aiuto - ad eccezione della scuola - quando i genitori si trovano in situazioni drammatiche; lo scarsissimo feeling con gli assistenti sociali; il fatalismo del destino del figlio che attenua il senso di colpa, senza connotarsi di progettualit\ue0; da parte dei professionisti, la necessit\ue0 che i genitori possano contare su una figura di riferimento (case-manager) presente sul territorio e su reti parentali e amicali culturalmente affini e/o meticciate; la rappresentazione di genitori in difficolt\ue0 per scarsa chiarezza nelle comunicazioni, a fronte di un\u2019immediata accettazione di sostegni. Da questa prima parziale lettura, la scuola risulta la realt\ue0 maggiormente in grado di corrispondere ai bisogni delle famiglie, accogliendole; ci\uf2 viene confermato dagli stessi insegnanti che richiedono, per\uf2, un maggior supporto dei servizi territoriali, anche riguardo all\u2019ampliamento della partecipazione delle famiglie migranti (con la presenza di mediatori culturali)

Multiplicity distributions inside parton cascades developing in a medium

The explanation of the suppression of high-pT hadron yields at RHIC in terms of jet-quenching implies that the multiplicity distributions of particles inside a jet and jet-like particle correlations differ strongly in nucleus-nucleus collisions at RHIC or at the LHC from those observed at e+e- or hadron colliders. We present a framework for describing the medium-induced modification, which has a direct interpretation in terms of a probabilistic medium-modified parton cascade, and which treats leading and subleading partons on an equal footing. We show that our approach can account for the strong suppression of single inclusive hadron spectra measured in Au-Au collisions at RHIC, and that this implies a characteristic distortion of the single inclusive distribution of soft partons inside the jet. We determine, as a function of the jet energy, to what extent the soft fragments within a jet can be measured above some momentum cut.Comment: 5 pages, 4 eps-figures; talk given at Hot Quarks 2006, Villasimius (Sardinia, Italy), May 15-20, 200