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Hermine Woehri (CERN)27/05/2012, 14:30Oral presentation
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elena Ferreiro (Universidade Santiago de Compostela)27/05/2012, 15:30Oral presentation
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Mateusz Ploskon (Lawrence Berkeley National Laboratory)27/05/2012, 17:00Oral presentation
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Guilherme Milhano (CENTRA-IST (Lisbon) and CERN-PH-TH)27/05/2012, 18:00Oral presentation
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Berndt Mueller (Duke University)28/05/2012, 09:15Hard QCD and QED probes hold the promise of providing controlled, rigorously calculable means of interrogating hot and dense QCD Matter, measuring its properties and determining its structure. While the RHIC has opened hard probes to experimental investigation, the LHC has extended the range of hard probe measurements by an order of magnitude. Data on jets, high-pT hadrons, quarkonia,...Go to contribution page
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Aaron Angerami (Columbia University)28/05/2012, 09:45Oral presentationMeasurements of inclusive jet and heavy quark jet suppression in relativistic heavy ion collisions are presented. The measurements were performed using Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$~TeV recorded with the ATLAS detector at the LHC during the 2010 Pb ion run. Results are obtained using calorimetrically reconstructed jets using the anti-kt algorithm with a per-event background...Go to contribution page
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Christof Roland (MIT)28/05/2012, 10:15Oral presentationThe energy loss of fast partons in hot and dense nuclear matter is studied in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV with the CMS detector at the LHC. Detailed studies of the dijet momentum balance and angular correlations are performed as a function of collision centrality and leading jet transverse momentum up to 350 GeV/c. Dijets in central collisions are...Go to contribution page
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Peter Christiansen (Lund University)28/05/2012, 11:15Oral presentationThe production of particles at high $p_T$ in pp collisions can be described using perturbative QCD. In Pb-Pb collisions the observed yield of high $p_T$ particles is much smaller than expected from binary scaling because of strong final state interactions with the surrounding dense medium. Experiments at RHIC have shown that this modification is very different for mesons and baryons. In the...Go to contribution page
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Andrea Beraudo (CERN)28/05/2012, 11:45Oral presentationProviding a unified description of the various "jet-quenching" observable nowadays available represents a deep challenge. Several model calculations are available on the market, mostly based on the factorization between an energy loss occurring at the partonic level in the medium and a standard time-delayed non-perturbative hadronization stage taking place in the vacuum. Two important...Go to contribution page
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Konrad Tywoniuk (Lund University)28/05/2012, 12:15Oral presentationAs a first step towards an understanding the physics of jet modifications in heavy-ion collisions, we analyze the radiation off a QCD antenna propagating through a quark-gluon plasma. The resulting spectrum is characterized in terms of the hardest scale of the problem. We show that this scale is either 1) the inverse size of the antenna as probed by the medium or 2) the maximal momentum...Go to contribution page
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Victoria Zhukova (University of Kansas)28/05/2012, 14:00Oral presentationMeasurements of the azimuthal anisotropy of charged hadrons are presented for PbPb collisions at sqrt(s_NN) = 2.76 TeV over an extended transverse momentum range. The data were collected with the CMS detector at the LHC. The anisotropy parameter (v_2) is extracted up to a significantly higher pT region than previous achieved, by correlating charged tracks with respect to the event plane...Go to contribution page
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Moon Dong Ho (Korea University)28/05/2012, 14:00Oral presentationThe Compact Muon Solenoid (CMS) is fully equipped to measure hard probes in the di-muon decay channel in the high multiplicity environment of nucleus-nucleus collisions. Such probes are especially relevant for studying the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. CMS has measured the nuclear modification factors of...Go to contribution page
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Horowitz Will (Department of Physics University of Cape Town)28/05/2012, 14:00Oral presentationWe present comparisons of the latest pQCD- and AdS/CFT-based energy loss models with the newest high-pT measurements from RHIC and LHC. Zero parameter predictions of energy loss from WHDG rigorously constrained to PHENIX pi0 RAA data show quantitative agreement with the measured azimuthal anisotropy and D meson suppression at LHC. pQCD predictions follow the qualitative trend of the LHC...Go to contribution page
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Michael Benzke (Technische Universität München (TUM))28/05/2012, 14:20Oral presentationThe jet quenching parameter \hat{q} describes the transverse momentum broadening of a high-energy parton moving through a thermal medium. In the past, several authors were able to relate this quantity to the expectation value of two light-cone Wilson lines. Recently, the results were reobtained in a systematic way by employing effective field theory methods (Soft-Collinear Effective Theory)....Go to contribution page
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Jens Wiechula (Physikalisches Institut, Universität Tübingen)28/05/2012, 14:20Oral presentationHeavy quarkonium states, such as the $J/\psi$, are expected to provide essential information on the properties of high-energy heavy-ion collisions where the formation of a Quark-Gluon Plasma is expected. The impact on the $J/\psi$ production of such a hot and dense medium formed in the early times of the collision has been extensively studied at SPS and RHIC energies. It is expected that due...Go to contribution page
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Takahito Todoroki (Tsukuba)28/05/2012, 14:20Oral presentationMeasurements of two particle correlations are important tools to dissect the interplay of hard-scattered partons and the hot dense medium created by ultra-relativistic heavy ion collisions. One of important topic of correlation measurements in heavy ion collisions is to evaluate the path-length dependence of parton energy loss and to discern the medium response to it. Another topic is to...Go to contribution page
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Francois Arleo (LAPTH)28/05/2012, 14:40Oral presentationQuarkonium nuclear suppression in p-A collisions at large xF can be accurately described in a model based on first principles (medium-induced gluon radiation) and depending on a single free parameter. Our results strongly support `parton energy loss' as a dominant effect in quarkonium nuclear suppression, and moreover give some clue on the quarkonium hadroproduction mechanism.Go to contribution page
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Rylan Conway (University of California, Davis)28/05/2012, 14:40Oral presentationMeasurements from the CMS experiment at the LHC of dihadron correlations for charged particles produced in PbPb collisions at a nucleon-nucleon centre-of-mass energy of 2.76 TeV are presented. The results are reported as a function of the particle transverse momenta and collision centrality over a broad range in relative pseudorapidity (delta-eta) and the full range of relative azimuthal angle...Go to contribution page
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Rajagopal Krishna (MIT Department of physics)28/05/2012, 14:40Oral presentationA holographic calculation of the quenching of a beam of gluons with typical momenta q shining through strongly coupled quark-gluon plasma shows that such a beam is attenuated rapidly over a distance of order q^{1/3} (pi T)^{-4/3} as it propagates at the speed of light, shedding trailing sound waves with momenta of order (pi T). At larger and larger q, the trailing sound wave becomes less and...Go to contribution page
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Jan Rak (Jyvaskyla Univesity, Finland)28/05/2012, 15:00Oral presentationThe ALICE collaboration has recently reported an observation of an enhanced intra-jet yield of charged particles associated with the high-pT trigger particle in central Pb-Pb collisions at √s_NN=2.76 TeV \cite{Aamodt:2011vg}. There are several possible explanations of the origin of this enhancement: (i) modifications of the fragmentation function, (ii) bias on the p_T distribution of the...Go to contribution page
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Marcus Bluhm (Laboratoire SUBATECH)28/05/2012, 15:00Oral presentationA firm knowledge of medium-induced energy loss mechanisms in the deconfined plasma state of QCD matter is essential for our understanding of phenomena such as strong jet quenching and high-pT hadron suppression observed in high energy nuclear collisions at RHIC and LHC. Based on perturbative QCD calculations, it is commonly accepted that the radiative energy loss contribution is dominant, ...Go to contribution page
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Miguel Angel Escobedo (Technische Universität München)28/05/2012, 15:00Oral presentationComputations with weakly-coupled plasmas and some lattice results suggest that the heavy quarkonium potential has an imaginary part that is important in order to study dissociation. This imaginary part is due to the scattering with partons in the medium in a process called quasi-free dissociation. At temperatures much below dissociation another process that is known to be important is the...Go to contribution page
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Ramona Vogt (LLNL and UC Davis)28/05/2012, 15:20Oral presentationWe assess the theoretical uncertainties on the inclusive J/psi production cross section in the Color Evaporation Model using values for the charm quark mass, renormalization and factorization scales obtained from a fit to the charm production data [1]. We use our new results to provide improved baseline comparison calculations at RHIC and the LHC. We calculate the fraction of J/psi...Go to contribution page
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Andrej Ficnar (Columbia University)28/05/2012, 15:20Oral presentationIn this talk, we explore phenomenological signatures of light quark jet quenching, modeled as falling strings within the AdS/CFT correspondence. In particular, we show that even in the simplest models, it is possible to obtain the correct qualitative behavior of the pion RAA at LHC, and we also present the quantitative predictions. We address the effect of the QCD conformal anomaly on this...Go to contribution page
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Jia JIANGYONG (Stony Brook University and BNL)28/05/2012, 15:20Oral presentationRecently, the study of harmonic flow coefficients v_n has been the focus of many experimental efforts in heavy-ion collisions at RHIC and the LHC. These coefficients are believed to be associated with the various shape components in the initial geometry, arising from fluctuations of the participating nucleons in the overlap region. The orientation of these harmonic flow (event plane or...Go to contribution page
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Laure MASSACRIER (Subatech Nantes)28/05/2012, 15:40Oral presentationJ/psi suppression induced by color screening of its constituents quarks was proposed 26 years ago as a signature of the formation of a quark gluon plasma in heavy-ion collisions. Recent results from ALICE in Pb-Pb collisions exhibit a smaller suppression with respect to SPS and RHIC previous measurements. The study of azimuthal anisotropy in particle production gives information on the...Go to contribution page
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Andreas Morsch (CERN)28/05/2012, 15:40Oral presentationIn central heavy-ion collisions at the LHC hot and dense matter is formed in which outgoing partons suffer significant energy loss. The quenched energy seems to dominantly reappear at low and intermediate pT, a pT region where collective effects dominate and jet reconstruction is not feasible. To characterize in-medium energy loss in this pT region, we analyse two-particle angular correlations...Go to contribution page
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Ben-Wei Zhang (Central China Normal University)28/05/2012, 15:40Oral presentationJets physics in heavy ion reactions is an important new area of active research at the Relativistic Heavy Ion Collider (RHIC) and at the Large Hadron Collider (LHC) that paves the way for novel tests of QCD multi-parton dynamics in dense nuclear matter. At present, perturbative QCD calculations of hard probes in elementary nucleon-nucleon reactions can be consistently combined with the effects...Go to contribution page
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Zaida Conesa del Valle (CERN)28/05/2012, 16:30Oral presentationThe production of the prompt charm mesons D0, D+, D∗+, and their antiparticles, in Pb–Pb collisions at the LHC, at a centre-of-mass energy sqrt(sNN) = 2.76 TeV per nucleon–nucleon collision, has been measured with the ALICE detector. The pt-differential production yields in the range 2 < pt < 16 GeV/c at central rapidity, |y| < 0.5, were used to calculate the nuclear modification factor RAA...Go to contribution page
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Michael Murray (University of Kansas)28/05/2012, 16:30Oral presentationMeasurements of the charged hadron multiplicity and transverse energy are presented for minimum bias PbPb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair. The number of charged hadrons was obtained by two different methods based on the inner silicon pixel system of the CMS detector at the LHC. One technique involved counting the number of reconstructed single particle hits...Go to contribution page
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Misha Veldhoen (Utrecht University)28/05/2012, 16:30Oral presentationAn important open question regarding hadronization in heavy-ion collisions is to understand the baryon enhancement at intermediate pT observed at RHIC. In this work we analyze the p/π ratio in the associated yield (pT < 5.0 GeV/c) correlated to a high-pT trigger (pT > 5.0 GeV/c) in central Pb–Pb collisions. For this analysis we used Pb–Pb data taken by the ALICE detector at a center of mass...Go to contribution page
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Robert Vertesi (Institute for Particle and Nuclear Physics, Wigner RCP, HAS)28/05/2012, 16:50Oral presentationNeutral pion production in \sqrt{sNN}=130 and 200 GeV central Au+Au collisions at the Relativistic Heavy Ion Collider has been found to be strongly suppressed in comparison to the expectations from properly scaled p+p collisions [1], while data from d+Au collisions showed no suppression [2]. This observation was one of the first convincing signatures of a strongly interacting partonic medium...Go to contribution page
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David Tlusty (NPI ASCR)28/05/2012, 16:50Oral presentationHeavy quarks are a unique probe to study the medium produced in ultra-relativistic heavy ion collisions. The dominant process of charm quark production at RHIC is believed to be initial gluon fusion which can be calculated in the perturbative QCD. The upper limit of FONLL calculation seems to be in good agreement with charm cross section measurements at mid-rapidity in $p+p$ collisions at...Go to contribution page
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Alan Davila (University of Texas at Austin)28/05/2012, 16:50Oral presentationInclusive Proton/pion ratios show an enhancement at intermediate transverse momentum (PT ~1.5 - 4.0 GeV/c) in central √sNN = 200 GeV Au+Au collisions compared to peripheral Au+Au and p+p collisions. This effect suggests a production mechanism, different from fragmentation, which is consistent with coalescence and recombination models. A high-ET trigger particle selects a surface-biased jet,...Go to contribution page
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Gabriel de Barros (Universidade de São Paulo)28/05/2012, 17:10Oral presentationWe present new, data-driven analysis methods for the measurement of reconstructed jets over a broad kinematic range, in the complex environment of heavy ion collisions. We utilize simple model calculations that contain the essential features of jet reconstruction in nuclear collisions at both energies, in order to assess systematic uncertainties of the methods due to large experimental...Go to contribution page
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Magdalena Djordjevic (Institute of Physics, University of Belgrade)28/05/2012, 17:10Oral presentationReliable predictions for jet quenching in ultra-relativistic heavy ion collisions require accurate computation of radiative energy loss. While all available energy loss calculations assume zero magnetic mass – in accordance with the one-loop perturbative calculations – different non-perturbative approaches report a non-zero magnetic mass at RHIC and LHC. We generalized the dynamical energy...Go to contribution page
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Yury Kharlov (Institute for High Energy Physics)28/05/2012, 17:10Oral presentationIdentified hadron spectra are considered as a sensitive probe for transport properties of strongly interacting matter produced in heavy ion collisions. The ALICE detector at the LHC studies pi0 and eta meson production via their two-photon decays by two complementary methods, using electromagnetic calorimeters and the central tracking system for photons converted to e+e- pairs on the material...Go to contribution page
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Krisztian Krajczar (MIT)28/05/2012, 17:30Oral presentationThe nuclear modification factor R_AA is one of the key signatures for the energy loss of fast partons traversing a QCD medium. Charged particle transverse momentum (pT) spectra have been measured by CMS for pp and PbPb collisions at the same collision energy per nucleon pairs, sqrt(s_(NN))=2.76 TeV, corresponding to integrated luminosities of 230 nb-1 and 150 ub-1, respectively....Go to contribution page
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Rongrong Ma (Yale University)28/05/2012, 17:30Oral presentationJet reconstruction and jet structure variables provide important information to study the interaction between hard scattered partons and the Quark-Gluon Plasma. This talk presents the measurement of the inclusive cross-section for fully reconstructed jets in pp collisions at \sqrt{s}=2.76 TeV, which provides an essential reference for jet measurements in Pb-Pb collisions at the same...Go to contribution page
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Giacomo Ortona (INFN Torino)28/05/2012, 17:30Oral presentationA Large Ion Collider Experiment (ALICE) is one of the four major experiments at the Large Hadron Collider (LHC), and it is dedicated to the study of ultra-relativistic heavy ion collisions, with the goal of investigating the properties of the high-density state of QCD matter produced in these collisions. The study of D meson production azimuthal anisotropy and the measurement of their...Go to contribution page
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Yacine Mehtar-Tani (IPhT (CEA-Saclay))28/05/2012, 17:50Oral presentationWe study the perturbative evolution of a jet via multiple gluon emissions induced by the interactions between the jet constituents and a dense QCD medium like a quark-gluon plasma. We focus on the typical medium-induced gluons emissions, for which the gluon formation time is much smaller than the overall size of the medium. We show that the typical time between two subsequent emissions is...Go to contribution page
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Michele Floris (CERN)28/05/2012, 17:50Oral presentation(on behalf of the ALICE Collaboration) The ALICE experiment measured charged particle production in $\sqrt{s_{NN}}=2.76$~TeV Pb-Pb collisions at the LHC. We report on results on charged particle multiplicity and transverse momentum spectra. All the results are presented as a function of centrality, estimated with a Glauber Monte Carlo fit to multiplicity distributions reconstructed in...Go to contribution page
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Pol Bernard Gossiaux (Subatech)28/05/2012, 17:50Oral presentationRecently, we have proposed a microscopic approach for the quenching and thermalisation of heavy quarks (HQ) in URHIC [1, 2, 3], assuming that they interact with light partons through both elastic and radiative processes evaluated by resorting to some parameterization of the running coupling constant, while those partons are spatially distributed along hydrodynamical evolution of the hot...Go to contribution page
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Thorsten Renk (University of Jyväskylä)29/05/2012, 09:00Oral presentationHigh P_T measurements of hard hadrons or jets at RHIC and LHC appear contradictory and in some cases counter-intuitive, but upon closer investigation they represent a coherent picture of jet-medium interaction physics which can be established with systematic comparisons of models against a large body of data. This picture is consistent with a perturbative QCD mechanism and does not require...Go to contribution page
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Alice Ohlson (Yale University)29/05/2012, 09:30Oral presentationThe propagation and modification of hard-scattered partons in the QGP can be studied using various types of jet and jet-like correlation measurements. The STAR detector with its full azimuthal and large pseudorapidity acceptance, as well as its wide transverse momentum coverage, is well-suited for these measurements. Correlations of neutral pions and jet-like clusters at forward rapidity in...Go to contribution page
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Jan Fiete Grosse Oetringhaus (CERN)29/05/2012, 10:00Oral presentationParticle correlations are a powerful tool to study collective effects and in-medium jet modification as well as their interplay in the hot and dense medium produced in central heavy-ion collisions. The talk presents measurements of two-particle correlations of inclusive charged and identified particles with the ALICE detector. We study the short-range correlation region and quantify the shape...Go to contribution page
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Charles Maguire (Vanderbilt University)29/05/2012, 10:55Oral presentationThe measurements of the anisotropic flow of single particles and particle pairs have provided some of the most compelling evidence for the creation of a strongly interacting quark-gluon plasma (sQGP) in relativistic heavy ion collisions, first at RHIC, and more recently at the LHC. Using PbPb collision data taken in the 2010 and 2011 heavy ion runs at the LHC, the CMS experiment has...Go to contribution page
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Soumya Mohapatra (Stony Brook University)29/05/2012, 11:20Oral presentationHadron correlations are important tools used to study the properties of the medium produced in relativistic heavy ion collisions. We present detailed measurements of flow harmonics $v_{2}$-$v_{6}$ via di-hadron correlations in broad $p_{T}$, $\Delta\eta$ and centrality ranges using the 2010 Pb+Pb data from ATLAS. These measurements are compared to the corresponding values obtained via...Go to contribution page
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Justin Frantz (Ohio University)29/05/2012, 11:45Oral presentation
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Derek Teaney (Stony Brook University)29/05/2012, 12:10Oral presentationI review the application of the AdS/CFT correspondence to heavy ion collisions. The talk will first review and critique available holographic calculations of energy loss, with an emphasis on the parametric similarities and differences between perturbation theory and the strongly coupled theory. Then the talk will summarize the results of current AdS/CFT motivated energy loss models and...Go to contribution page
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Brian Cole (Columbia University)29/05/2012, 12:35Oral presentation
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Peter Steinberg (Brookhaven National Laboratory)29/05/2012, 14:15Oral presentationDirect photons are a powerful tool in heavy ion collisions. Their production rates provide access to the initial state parton distribution functions, which are expected to be modified by nuclear effects. They also provide a means to calibrate the expected energy of jets that are produced in the medium, and thus are a tool to probe the physics of jet quenching more precisely both through jet...Go to contribution page
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Jorge Casalderrey-Solana (U. de Barcelona)29/05/2012, 14:15Oral presentationWe study the time structure of vacuum jet evolution via a simple uncertainty principle estimate in the kinematic range explored by current heavy ion collisions at the LHC. We observe that a large fraction of the partonic splittings occur at large times, of the order of several fm. We compare the time distribution of vacuum splittings with the distribution of path lengths traversed by jets in a...Go to contribution page
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Carlos Lourenco (CERN)29/05/2012, 14:15Oral presentationUsing large data samples of di-muon events, CMS has performed detailed measurements in the field of quarkonium production. Differential cross-sections of J/psi, psi(2S) and Y(nS) states in pT and rapidity will be presented, separated in prompt and non-prompt contributions for the charmonium case: experimental results are compared with recent predictions in the context of NLO nonrelativistic...Go to contribution page
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Mauricio Martinez Guerrero (Universidade de Santiago de Compostela)29/05/2012, 14:35Oral presentationRadiative interferences in the multi-parton shower is the building block of QCD jet physics in vacuum. The presence of a hot medium made of quarks and gluons is expected to alter this interference pattern. To study such effects, we derive the gluon emission spectrum off an "asymptotic quark" traversing a hot and dense QCD medium at first order in the medium density. The resulting induced...Go to contribution page
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Yen-Jie Lee (CERN)29/05/2012, 14:35Oral presentationIsolated photon production is measured in pp and PbPb collisions at nucleon-nucleon center-of-mass energies of 2.76 TeV in the pseudorapidity range |eta| < 1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with NLO perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential...Go to contribution page
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Claudio Geuna (CEA Saclay Irfu/SPhN)29/05/2012, 14:35Oral presentationOpen heavy-flavour and J/psi production measurements are powerful tools to test pQCD calculations in proton-proton collisions at the new LHC energy regime. In addition, the measurement of open heavy-flavour and J/psi production in proton-proton collisions provides the necessary reference for the ALICE Pb-Pb program. The ALICE experiment at the LHC collected proton-proton collisions at...Go to contribution page
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Yujiao Chen (Columbia university)29/05/2012, 14:55Oral presentationHeavy quarks are very important probes to study the hot, dense medium produced in heavy ion collisions. Heavy quarks are produced at a relatively early stage of the nucleus-nucleus collision and they may have a reduced level of gluon radiation due to a suppression of small angle gluon radiation known as the ‘dead cone effect.’ The first results on the suppression of the J/ψ as a function of...Go to contribution page
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Lamia Benhabib (LLR-Ecole Polytechnique)29/05/2012, 14:55Oral presentationThe unprecedented centre-of-mass energy available at the LHC offers unique opportunities for studying the properties of the strongly-interacting QCD matter created in PbPb collisions at extreme temperatures and very low parton momentum fractions. The Compact Muon Solenoid (CMS) is fully equipped to measure leptonic decays of electroweak probes in the high multiplicity environment of...Go to contribution page
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Mindaugas Lekaveckas (MIT)29/05/2012, 14:55Oral presentationWe calculate P(k_perp), the probability distribution for an energetic parton propagating for a distance L through a medium to pick up transverse momentum k_perp, for a medium consisting of weakly coupled quark-gluon plasma. We use full or HTL self-energies in appropriate regimes, resumming each in order to find the leading large-L behavior. We estimate the jet quenching parameter and compare...Go to contribution page
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Abhijit Majumder (Wayne State University)29/05/2012, 15:15Oral presentationWe present a framework where first principles calculations of jet modication may be carried out in a non-perturbative thermal environment. As an example of this approach, we compute the leading order contribution to the transverse momentum broadening of a high energy (near on-shell) quark in a thermal medium. This involves a factorization of a non-perturbative operator product from the...Go to contribution page
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Diego Stocco (Subatech)29/05/2012, 15:15Oral presentationThe main goal of the ALICE experiment is the study of the properties of the strongly-interacting matter at very high energy density which is formed in ultra-relativistic heavy-ion collisions at the LHC. Heavy-flavours (charm and beauty) have an important role in the investigation: being produced in the early stage of the collision, they are sensitive probes of the Quark-Gluon Plasma and allow...Go to contribution page
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Zvi Citron (Weizmann Institute of Science)29/05/2012, 15:15Oral presentationThe color neutral Z boson is an excellent probe of the hot dense matter produced in heavy ion collisions. The products of the Z boson di-lepton decays do not interact with the dense color matter, thus, the Z boson allows us insight into the initial hard scattering that produced it and provides a clean test of our understanding of the collision. The ATLAS experiment has measured Z->ee and...Go to contribution page
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Jie Zhao (Shanghai Institute of Applied Physics/ Lawrence Berkeley National Lab)29/05/2012, 15:35Oral presentation
Dilepton production has been proposed to serve as a penetrating probe for the hot and dense medium created in high-energy nuclear collisions. Their small final-state interaction cross sections, let dileptons escape the interaction region undistorted. Since dileptons originate from all stages of a heavy ion reaction, their sources vary with the kinematic phase space under consideration: In the...
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Kenneth Read (ORNL and University of Tennessee)29/05/2012, 15:35Oral presentationMeasurement of the production of heavy quarks in heavy ion collisions can be used to probe the early stages of the created medium, study hot and cold nuclear matter effects, and test theoretical predictions concerning quark energy loss and initial-state effects. This is a current area of active research in the field and it is important to extend such measurements to the forward region. PHENIX...Go to contribution page
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Jose Guilherme Milhano (CENTRA-IST (Lisbon) and CERN-PH-TH)29/05/2012, 15:35Oral presentationThe observation of a significant enhancement of the dijet asymmetry in PbPb collisions as compared to the pp reference case, compounded with the absence of modication of the azimuthal dijet distribution, led us to highlight the importance of medium induced transverse transport of soft quanta as a source of jet energy loss. Here, we extend our analysis and explore the consequences of 'jet...Go to contribution page
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Silvia Masciocchi (GSI Darmstadt)30/05/2012, 09:00Oral presentationHeavy quarks, charm and beauty, are excellent probes to investigate QCD processes in hadronic interactions, and to characterize the deconfined medium produced in high-energy heavy-ion collisions, the Quark-Gluon Plasma. They are produced dominantly through hard partonic scattering processes in the earliest stage of the hadronic collisions and thus they experience the whole history of the...Go to contribution page
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Torsten Dahms (LLR, Ecole Polytech., IN2P3-CNRS, France)30/05/2012, 09:30Oral presentationThe Compact Muon Solenoid (CMS) is fully equipped to measure quarkonia in the di-muon decay channel in the high multiplicity environment of nucleus-nucleus collisions. Quarkonia are especially relevant for studying the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. CMS has measured the nuclear modification factors of...Go to contribution page
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Olaf Kaczmarek (Bielefeld University)30/05/2012, 10:00Oral presentationI will give a review on recent developments in lattice QCD studies for quarkonia in the quark gluon plasma medium. I will discuss recent progress in the extraction of spectral properties from lattice QCD calculations of hadronic correlation functions. Besides medium modifications of bound states and their dissociation in the plasma I will focus on transport coefficients, like heavy quark...Go to contribution page
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Christophe Suire (CNRS-IN2p3)30/05/2012, 11:00Oral presentationHeavy quarkonium states are expected to provide essential information on the properties of the high-density strongly-interacting system formed in the early stages of heavy-ion collisions. In particular the J/psi suppression, in heavy-ion collisions, via color screening mechanism, can be seen as a direct effect of deconfinement. During 25 years, the J/psi suppression has been extensively...Go to contribution page
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Alexander Rothkopf (Institute for Theoretical Physics, University of Bern)30/05/2012, 11:30Oral presentation
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Manuel Calderon De La Barca Sanchez (UC Davis)30/05/2012, 12:00Oral presentationHeavy flavor production is a useful tool to study the medium produced in heavy ion collisions. We will present results on production of charm hadrons via the reconstruction of D0 and D* mesons, and compare them to FONLL calculations. The nuclear modification factor of D mesons can then be used to study medium effects. We will also present results on charmonium and bottomonium production. By...Go to contribution page
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Anthony Frawley (Florida State University)30/05/2012, 12:30Oral presentationMeasurements of cross section modifications for hard processes that take place in a nuclear target provide information about the modification of parton densities in nuclei at low Bjorken $x$. This is interesting because it illuminates the physics of QCD at high parton density, and also because it provides a baseline against which the modification of cross ssections for hard processes in...Go to contribution page
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Alexander Milov (Department of Particle Physics and Astrophysics Weizmann Institute of Science)31/05/2012, 09:00Oral presentationThe color neutral bosons are an unparalleled probes of the hot and dense matter produced in relativistic heavy ion collisions at LHC. Because the decay products do not carry color charges, the W and Z bosons allows us insight into the initial hard scattering that produced it and provides a clean test of our understanding of the collision. In particular, the yield of bosons in heavy ion...Go to contribution page
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Begona De La Cruz (CIEMAT, Spain)31/05/2012, 09:30Oral presentationElectroweak gauge bosons, $\gamma$, W and Z, do not participate in the strong interaction, and thus constitute clean probes of the initial state of nucleus-nucleus collisions. The comparison of their production cross-sections in pp and in nuclear collisions provides an estimate of the nuclear parton distribution functions. Despite the low production cross section of weak bosons compared to...Go to contribution page
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Charles Gale (McGill University)31/05/2012, 10:00Oral presentationI review the theory behind the emission of electromagnetic radiation in relativistic collisions. The rates for photon and lepton pair production are examined, both for a quark-gluon plasma and for a hadronic gas at finite temperatures and densities. A special emphasis is placed on the connection between electromagnetic spectra and the details of modern 3D hydrodynamic simulations of...Go to contribution page
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Javier L Albacete (IPN Orsay)31/05/2012, 11:00Oral presentationThe forthcoming LHC run on p+Pb collisions will offer a unique possibility to explore the small-x regime of QCD. I shall review the physics prospects for different observables within the Color Glass Condensate framework: from multiplicity distributions, and single inclusive spectra to two-particle correlations. I will discuss in detail the quantitative challenges for a precise discrimination...Go to contribution page
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Kari J. Eskola (Department of Physics, University of Jyväskylä)31/05/2012, 11:25Oral presentationI will present an overview of the nuclear parton distribution functions (nPDFs). I will first discuss the developments in the DGLAP-based global analysis during the last years. In the latter part of the talk, I will focus on the extraction of the spatial dependence of the globally analysed nPDFs, which has led to the new spatially dependent nPDFs called EPS09s and EKS98s (“s” for spatial)....Go to contribution page
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Elisa Incani (CA)31/05/2012, 11:55Oral presentation
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Ms Deepa Thomas (Utrecht University)31/05/2012, 12:00
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Dr Rupa Chatterjee (University of Jyväskylä, Finland)31/05/2012, 12:05
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Dr Baldo Sahlmueller (Stony Brook University)31/05/2012, 12:10
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Carlos Salgado (Roma Univ. La Sapienza)31/05/2012, 12:25
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Yetkin Yilmaz (MIT)31/05/2012, 14:00Oral presentationJet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the CMS detector at the LHC. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching....Go to contribution page
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Francois Gelis (Institut de Physique Theorique)31/05/2012, 14:00Oral presentationIn the color glass condensate framework, the initial state of the system formed immediately after the collision of two heavy ions at high energy can be represented as a superposition of a classical color field and gaussian quantum fluctuations. This approximation is substanciated by results that show that all the leading logarithms of the collision energy are universal and can be factorized...Go to contribution page
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Olga Hajkova (Czech Technical University in Prague)31/05/2012, 14:00Oral presentationDue to their large masses, charm and bottom quarks, are mostly produced during the initial phase of collisions via gluon fusion. Non-photonic electrons (NPE) are mainly produced by semileptonic decays of D and B mesons, hence the study of NPE in hadron-hadron and ion-ion collisions provides the information about heavy quarks production as well as the medium properties. In order to interpret...Go to contribution page
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Jamal Jalilian-Marian (Baruch College)31/05/2012, 14:20Oral presentationDi-hadron angular correlations in the forward rapidity region of proton-nucleus collisions probe multi-gluon correlators (n-point functions of Wilson lines) in the wave function of target nucleus at small x and thus, provide a more detailed picture of QCD dynamics at high energy (CGC). The Renormalization Group equations that govern the energy dependence of these n-point functions will...Go to contribution page
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Sourav Tarafdar (Banaras Hindu University, Varanasi, India)31/05/2012, 14:20Oral presentationHeavy quarks are one of the most valuable probes for the matter produced in relativistic heavy ion collisions at RHIC. PHENIX experiment being designed specifically to study leptons, so electrons from the decay of heavy quarks acts as one of the most important tools in PHENIX for measurement of heavy quarks. Measurements of electron spectra at mid rapidity region has been done by PHENIX in...Go to contribution page
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MArtin Rybar (CERN)31/05/2012, 14:20Oral presentationJet quenching in the hot and dense medium created in ultra-relativistic heavy ion collisions is a well-established experimental phenomenon at RHIC. It has long been anticipated that the LHC heavy ion program would substantially advance the study of jet quenching by providing access to highly energetic jets and by measuring fully-reconstructed jets. Immediately following turn-on of the LHC in...Go to contribution page
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Marco Monteno (INFN Torino)31/05/2012, 14:40Oral presentationA refined version of a multi-step calculation of heavy-flavour observables in pp and AA collisions has been developed, based on pQCD at NLO accuracy followed by parton shower evolution to describe heavy-quark production and on the relativistic Langevin equation to describe their stochastic evolution in the QCD plasma. Then, hadronization is modeled through an implementation of the available...Go to contribution page
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Marta Verweij (Utrecht University)31/05/2012, 14:40Oral presentationWe report a measurement of transverse momentum spectra of ets detected with the ALICE detector in Pb-Pb collisions at $\sqrt{s_NN}$=2.76 TeV. Jets are reconstructed from charged particles using the anti-$k_{T}$ jet algorithm. The background from soft particle production is determined for each event and subtracted. The remaining influence of underlying event fluctuations is quantified by...Go to contribution page
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Xin-Nian Wang (Central China Normal University and Lawrence Berkeley National Laboratory)31/05/2012, 14:40Oral presentationWithin the framework of generalized collinear factorization in perturbative QCD (pQCD), we study the effect of initial multiple parton scattering and induced parton energy loss in Drell-Yan (DY) process in proton-nucleus collisions. We express the contribution from multiple parton scattering and induced gluon radiation to the DY dilepton spectra in terms of nuclear modified effective beam...Go to contribution page
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Paloma Quiroga-Arias (LPTHE, Univ. Paris 6 and CNRS)31/05/2012, 15:00Oral presentationThe forthcoming p+Pb run at the LHC will provide crucial in formation on the initial state effects of heavy ion collisions and on the gluon saturation phenomena. In turn, most of the saturation inspired phenomenology in heavy ion collisions borrows substantial empiric information from the analysis of e+p data, where abundant high quality data on the small-x kinematic region is available....Go to contribution page
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Jan Uphoff (Goethe University Frankfurt)31/05/2012, 15:00Oral presentationHeavy flavors are important probes to study the early phase of ultra-relativistic heavy ion collisions at RHIC and LHC. We present results on the production and space-time evolution of heavy quarks and J/psi in the quark gluon plasma within the partonic transport model Boltzmann Approach to MultiParton Scatterings (BAMPS). Heavy quarks interact with the medium via binary and radiative...Go to contribution page
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Dennis Perepelitsa (Columbia University)31/05/2012, 15:00Oral presentationJet reconstruction in heavy ion collisions at RHIC and the LHC is becoming a popular tool to explore medium effects including the energy loss and modified fragmentation of hard-scattered partons. In p+A and d+A collisions, reconstructed jets are important for evaluating cold nuclear matter effects such as the impact parameter dependence of nuclear parton distribution functions and initial...Go to contribution page
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Amir Rezaeian (Universidad Tecnica Federico Santa Maria)31/05/2012, 15:20Oral presentationI will show the results of our recent investigation of the inclusive hadron and prompt photon production in proton (deuteron)-nucleus (pA) collisions at RHIC and the LHC within the Color Glass Condensate (CGC) framework. We investigate the contribution of inelastic and elastic processes to single inclusive hadron production in proton-proton and pA collisions at RHIC and the LHC. Using the...Go to contribution page
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MinJung Kweon (University of Heidelberg)31/05/2012, 15:20Oral presentationThe medium-induced parton energy loss is expected to depend on its mass and colour charge. At the LHC, heavy quarks are copiously produced. This allows us to provide new constraints on partonic energy loss mechanisms in the medium produced in the heavy-ion collisions. The yield of electrons from semileptonic heavy-flavour decays has been measured at mid-rapidity \mbox{($|y| < 0.8$)} in Pb-Pb...Go to contribution page
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Christopher Coleman-Smith (Department of Physics, Duke University)31/05/2012, 15:20Oral presentationWe present a systematic study of dijet suppression at RHIC and the LHC using the VNI/BMS parton cascade. We examine the medium modification of the dijet asymmetry Aj and the energy distribution within the dijets (jet-shape). Understanding the sensitivity of these observables to properties of the deconfined medium and to experimental factors is vital if dijets are to be useful for QCD...Go to contribution page
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Liliana Apolinário (Universidade de Santiago de Compostela)31/05/2012, 15:40Oral presentationIn order to asses the ability of jet observables to constrain the characteristics of the medium produced in heavy-ion collisions at the LHC, we investigate the influence of background subtraction and jet quenching on jet reconstruction, with focus on dijet asymmetries as currently studied by ATLAS and CMS. Using two models for the background, a full simulation and a toy model, we examine the...Go to contribution page
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Brian Cole (Columbia University)31/05/2012, 15:40Oral presentationThe Large Hadron-electron Collider LHeC is a proposed facility at CERN to collide electrons and positrons against the LHC beams at center-of-mass energies around 1 TeV per nucleon, with the aim of studying previously unexplored kinematical regions of the hadron and nuclear wave functions. After a brief physical motivation, I will present the project. Then I will focus on the opportunities for...Go to contribution page
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Mr Min He (Cyclotron Institute, Texas A&M University)31/05/2012, 15:40Oral presentationWe evaluate heavy-flavor (HF) transport in relativistic heavy ion collisions within a nonperturbative (strong-coupling) framework. In the Quark-Gluon Plasma, heavy-quark diffusion coefficients are obtained from a potential-based T-matrix approach, which builds up resonance correlations toward the phase transition region. Those resonance correlations are also utilized for hadronizing heavy...Go to contribution page
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Heikki Mäntysaari (University of Jyväskylä)31/05/2012, 16:30Oral presentationSingle inclusive hadron production in the forward rapidiy region in deuteron-gold collisions is well understood in the Color Glass Condensate (CGC) framework. As a complement to single inclusive spectra, detailed information is obtained with two-particle correlations. Recent measurements of the azimuthal angle correlations at RHIC have shown that there is a strong suppression of the...Go to contribution page
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camelia mironov (LLR/Ecole polytechnique)31/05/2012, 16:30Oral presentationThe Compact Muon Solenoid (CMS) is fully equipped to measure hard probes in the di-muon decay channel in the high multiplicity environment of nucleus-nucleus collisions. Such probes are especially relevant for studying the quark-gluon plasma since they are produced at early times and propagate through the medium, mapping its evolution. CMS has measured the nuclear modification factors of Y(1S)...Go to contribution page
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Lai Yue Shi (MIT)31/05/2012, 16:30Oral presentationModification of jets transitioning through the quark–gluon plasma (QGP), or quenching, has been well established by the RHIC and LHC data, using particle correlation and recently, reconstructed jets. At LHC, the first measurement of the jet quenching employed dijets. However, the advantage of the large yield of dijets is offset by loss of the perturbative final state information, as both jets...Go to contribution page
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Rainer Fries (Texas A&M University)31/05/2012, 16:50Oral presentationWe investigate the correlations of photons produced by Compton back scattering and annihilation of fast quarks in quark gluon plasma with their away-side jets. Compton back scattering and quark annihilation into photons effectively act as jet-photon conversion mechanisms and were originally proposed as novel electromagnetic sources in heavy ion collisions in Phys. Rev. Lett. 90, 132301 (2003)....Go to contribution page
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Richard Seto (University of California, Riverside)31/05/2012, 16:50Oral presentationThe field of Relativistic Heavy Ion Physics has made great strides in the past decade with the establishment of the strongly interacting Quark Gluon Plasma (sQGP) in high energy collisions of heavy ions at the Relativistic Heavy Ion Collider (RHIC) and now at the LHC. Experience has taught us that large rapidity coverage, as well as careful measurements of cold nuclear matter will be...Go to contribution page
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Georg Wolschin (Heidelberg University)31/05/2012, 16:50Oral presentationWe suggest that gluon-induced dissociation and screening of the Y(nS) states together with feed-down explain the suppression of the Y(2S+3S) states relative to the Y(1S) ground state that has been observed by CMS in PbPb collisions at sqrt(s_NN) = 2.76 TeV at the CERN LHC. The minimum-bias gluodissociation cross sections of the 1S-3S states are calculated using a screened Cornell potential...Go to contribution page
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DIONYSIS TRIANTAFYLLOPOULOS (ECT*, Trento)31/05/2012, 17:10Oral presentationAt high energy and/or for large atomic numbers the wave-function of a generic hadron is dominated by gluon modes with soft longitudinal momenta and high occupation numbers, which can reach the state of saturation. This state, known as the Color Glass Condensate (CGC), is universal and can manifest itself in any hadronic process involving small-x partons, like deep inelastic scattering and...Go to contribution page
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Molnar Denes (Purdue University)31/05/2012, 17:10Oral presentationThere has been a lot of interest in testing radiative energy loss calculations against data from RHIC and the LHC. It is customary, as in the Gyulassy-Levai-Vitev (GLV) approach, to formulate the energy loss of a jet parton as a line integral from the production point along a straight-line trajectory. Calculations then account for variations in pathlength with jet origin and direction, and...Go to contribution page
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Shawn Whitaker (Iowa State University)31/05/2012, 17:10Oral presentationThe suppression of quarkonia in heavy ion collisions has long been thought to provide an indication of the temperature dependent Debye screening length of color charge in the quark gluon plasma. A large sample of d+Au and Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV has been collected by PHENIX in 2008 and 2010. The large statistical sample allows for both the observation of Upsilon in the hot...Go to contribution page
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Alessandro Buzzatti (Columbia University)31/05/2012, 17:30Oral presentationJet Flavor Tomography is a powerful tool used to probe the properties of Quark Gluon Plasma formed in heavy ion collisions at RHIC and LHC. A new Monte Carlo model of jet quenching developed at Columbia University, CUJET1.0, was applied to predict the jet flavor and centrality dependence of some of the main phenomenological observables, the nuclear modification factor $R_{AA}$ and the elliptic...Go to contribution page
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Anthony Kesich (University of California, Davis)31/05/2012, 17:30Oral presentationThermal suppression of quarkonium production in heavy-ion collisions, due to Debye screening of the quark-antiquark potential, has been proposed as a clear signature of quark-gluon plasma (QGP) formation. At RHIC energies, the \$Upsilon meson is a clean probe of the early system thanks to negligible levels of enhancement from b-bbar recombination and non-thermal suppression from co-mover...Go to contribution page
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Ilkka Helenius (University of Jyväskylä, Department of Physics)31/05/2012, 17:30Oral presentationThe knowledge of the parton distribution functions (PDFs) is essential for interpreting any hard-process results from hadronic and nuclear collisions. The nuclear modifications of PDFs have been successfully determined through a global DGLAP analysis e.g. in the sets EKS98 and more recently EPS09. So far the nuclear PDFs (nPDFs) in the global fits have been taken to be spatially independent....Go to contribution page
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Clint Young (McGill University)31/05/2012, 17:50Oral presentationThe reconstruction of jets in heavy-ion collisions provides insight into the dynamics of hard partons in media. Unlike the spectrum of single hadrons, the spectrum of jets is highly sensitive to $\hat{q}_{\perp}$, as well as being sensitive to partonic energy loss and radiative processes. We use MARTINI, an event generator, to study how finite-temperature processes at leading order affect...Go to contribution page
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Wei-Tian Deng (Frankfurt Institute for Advanced Studies)31/05/2012, 17:50Oral presentationMultiple hard and semi-hard parton scatterings in high-energy $p+A$ collisions involve multi-parton correlation in both momentum and flavor inside the projectile proton which will lead to modification of the final hadron spectra relative to that in $p+p$ collisions. Such modification of final hadron transverse momentum spectra in $p+A$ collisions is studied within HIJING 2.1 Monte Carlo model...Go to contribution page
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Jean-Philippe Lansberg (IPNO - Paris-Sud U. - CNRS/IN2P3)31/05/2012, 17:50Oral presentationIn the first part, I will discuss the impact of QCD corrections on the P_T differential cross section for Upsilon production in pp collisions at RHIC, Tevatron and LHC energies, as well as the behaviour of the differential cross section in rapidity. I will discuss the very good agreement between the parameter-free predictions of the Colour-Singlet Model and the first LHC data, especially in...Go to contribution page
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Tuomas Lappi (University of Jyväskylä)31/05/2012, 18:10Oral presentationMultiparticle correlations, such as the "ridge" effect in pp and AA collisions and forward dihadron correlations in pA collisions, are an important probe of the strong color fields that dominate the initial stages of a heavy ion collision. We argue that the Color Glass Condensate framework provides the most natural way to understand them. We describe recent progress in understanding...Go to contribution page
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Che-Ming Ko (Texas A&M University)31/05/2012, 18:10Oral presentationUsing the hydrodynamic model to describe the dynamics of heavy ion collisions, we have studied quarkonia production in these collisions by including both their dissociation in initial cold nuclear matter and subsequently produced quark-gluon plasma [1-4]. For the latter, we used the screened Cornell potential and the next-to-leading order perturbative QCD to determine, respectively, their...Go to contribution page
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Lijuan Ruan (Brookhaven National Laboratory)01/06/2012, 09:00Oral presentationDi-leptons are ideal probes of the strongly interacting hot, dense medium created at RHIC. They are not affected by the strong interaction once produced, therefore they can probe the whole evolution of the collision. In different mass regions, di-leptons can be used to probe vector meson in-medium modifications, Quark Gluon Plasma (QGP) thermal radiations, and color-screening features of...Go to contribution page
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Axel Drees (Stony Brook University)01/06/2012, 09:30Oral presentationOver the past years PHENIX has published multiple results on electron-positron pairs and direct photons from Au+Au collisions, which reveal a number of puzzling and not understood features. First measurements of direct photons at momenta below 3 GeV point towards a significant thermal yield consistent with initial temperatures well above the transition temperature. However, this thermal source...Go to contribution page
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Peter Jacobs (Lawrence Berkeley National Laboratory)01/06/2012, 10:00Oral presentationThis talk will present a global view of what has been learned to date from ALICE data about the interaction of jets with the hot medium generated in high energy nuclear collisions at the LHC. The discussion will incorporate measurements of inclusive charged and identified hadrons, hadron correlations, heavy flavor measurements, and first ALICE measurements of fully reconstructed jets,...Go to contribution page
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01/06/2012, 11:00Oral presentation
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Jurgen Schukraft (CERN)01/06/2012, 11:30Oral presentation
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01/06/2012, 12:00
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Mr Sandro Bjelogrlic (Utrecht University)Poster presentationAs a consequence of their relatively high mass, heavy-flavour quarks, produced in heavy-ion collisions, are sensitive probes of the interaction dynamics inside the hot and dense QCD matter. Since heavy quarks are produced in pairs during the initial stage of the collision, before the formation of the QCD medium, the measurement of heavy-flavour hadron production provides sensitive...Go to contribution page
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Ms Deepa Thomas (ERC-Research Group QGP-ALICE, Utrecht University)Poster presentationIn ultra-relativistic heavy-ion collisions, heavy quarks, i.e. charm and beauty, are produced in the early stage by hard scattering processes and experience the full evolution of the strongly-interacting system. They therefore carry relevant information on the properties of the medium. In such collisions, heavy flavour hadrons can be measured from electrons produced in their semileptonic...Go to contribution page
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Poster presentationThe measurement of the charm production cross section in pp collisions at the LHC allows one to test the perturbative QCD predictions in a new energy regime. Furthermore, it provides a reference for charm measurements in Pb-Pb collisions in which heavy quarks are expected to be sensitive probes for the properties of the medium. D+s mesons have been reconstructed at mid-rapidity with the ALICE...Go to contribution page
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David D'Enterria (tbc) (CERN-PH-TH), Johannes Wessels (WWU Muenster and CERN)
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Mrs Ranjita Mohapatra (Institute of Physics)Poster presentationWe investigate the effects of explicit breaking of Z(3) symmetry due to the presence of dynamical quarks on the formation and evolution of Z(3) walls and associated QGP strings within Polyakov loop model. We carry out numerical simulations of the first order quark-hadron phase transition via bubble nucleation (which may be appropriate, for example, at finite baryon chemical potential)...Go to contribution page
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Berndt Mueller (Duke University)Oral presentation
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Mr Michal Vajzer (Nuclear Physics Institute of Academy of Sciences of Czech Republic)Poster presentationJets, collimated sprays of particles associated with hard partons, are an invaluable tool in testing QCD and probing structure and properties of hot and dense nuclear matter created in high energy heavy-ion collisions. Jets enable us to study the evolution from hard-scattering through fragmentation to hadronisation and test modification of these processes in presence of nuclear medium with...Go to contribution page
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Dr Sergey Petrushanko (Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University)Poster presentationThe started LHC heavy ion program makes it possible to probe new frontiers of the high temperature Quantum Chromodynamics. The first LHC data on multiplicity, hadron spectra, elliptic flow and femtoscopic correlations from PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed in the framework of the HYDJET++ model which describes relativistic heavy ion collisions as a...Go to contribution page
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Alice Ohlson (Yale University)Poster presentationA measurement of the correlation between the axes of reconstructed jets and the reaction plane of the bulk medium (known as jet v2) and the higher-order participant planes (jet vn) provides information on the pathlength dependence of medium-induced parton energy loss as well as biases in jet-finding methods. Additionally, knowledge of jet vn and the ability to reconstruct the event plane in...Go to contribution page
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Elisa Incani (INFN)Poster presentationThe measurement of light vector meson production (rho,omega,phi) in pp collisions provides insight into soft Quantum Chromodynamics (QCD) processes in the LHC energy range. Calculations in this regime are based on QCD inspired phenomenological models that must be tuned to the data, in particular for hadrons that contain the u, d, s quarks. Moreover, light vector meson production provides...Go to contribution page
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Mr Markus Heide (Institut fuer Kernphysik, WWU Münster)Poster presentationThe measurement of the production cross-section of B mesons in pp collisions at LHC energies is important in two respects. First, it allows one to test perturbative quantum chromodynamics calculations. Secondly, it provides an essential reference for studies in heavy-ion collisions, in which a hot and dense medium, the quark-gluon plasma (QGP), is expected to be formed. When passing through...Go to contribution page
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Poster presentationIn ultra-relativistic heavy-ion collisions, heavy quarks are sensitive probes to test the medium properties, since they are formed at shorter time scale with respect to the deconned state. These quarks can interact with the medium and lose energy via collisions and gluon radiation. The nuclear modication factor (RAA), obtained by comparing heavy avour production yields in pp and heavy-ion...Go to contribution page
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Giovanni Antonio Chirilli (Lawrence Berkeley National Laboratory)Oral presentationWe demonstrate the QCD factorization for inclusive hadron production in pA collisions in the saturation formalism at one-loop order. We explicitly calculate both real and virtual gluon radiation diagrams and show explicitly that, the collinear divergences associated with the incoming parton distribution of the nucleon and the outgoing fragmentation function of the final state hadron, as well...Go to contribution page
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Dr Cynthia Hadjidakis (IPN Orsay)Poster presentationIn heavy-ion collisions at the LHC, the ALICE experiment is studying nuclear matter at very high energy density where the formation of a Quark Gluon Plasma (QGP) is expected. Quarkonium production is an important probe to characterize the properties of the QGP as it gives access to the early stages of the collision. In 2010 and 2011, the LHC provided Pb-Pb collisions at √s = 2.76 TeV per...Go to contribution page
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Mrs Paola Pagano (SA)Poster presentationA Large Ion Collider Experiment (ALICE) has been designed for the study of strongly interacting matter created in heavy-ion collisions at LHC energies. The measurement of heavy-flavour hadron production cross-sections in high energy proton-proton collisions provides interesting insights into QCD processes and is important as a reference for heavy-ion studies. In ALICE, the production of...Go to contribution page
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Mr Martin Voelkl (University of Heidelberg)Poster presentationHeavy quarks are relevant probes of the QCD medium produced in high-energy heavy ion collisions. Indeed, medium-induced energy loss is expected to depend on the parton mass and color charge. Charm and beauty quarks are created early in the collision and should thus traverse much of the QCD medium created. In 2010 and 2011, pp collisions at $\sqrt{s} = 7$ TeV and PbPb collisions at...Go to contribution page
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Poster presentationThe ALICE experiment at the CERN-LHC has accumulated data on pp and Pb--Pb collisions in the past two years. Designed for exploring the properties of hot and dense matter formed in heavy-ion collisions, the ALICE Time Projection Chamber (TPC) has the capability to measure the transverse momentum ($p_T$) of charged particles in a broad $p_T$ range for $p_T > $ 150 MeV/c. \\ The transverse...Go to contribution page
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Oral presentation
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