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Contribution List

Displaying 86 contributions out of 86
ALICE is one of the four big experiments of the LHC at CERN. Located 40 m underground with 30 m of overburden rock it can also operate to detect atmospheric muons produced by cosmic ray interactions with the atmosphere. The analysis of the data collected with cosmic triggers from 2010 until 2013, corresponding to around 30 days of live time, will be presented. Exploiting the specific capability o ... More
Presented by Dr. Arturo FERNANDEZ TELLEZ on 14 Sep 2017 at 18:25
As active data taking has moved to the LHC at CERN, more and more LHC data have been included into fits of parton distribution functions. An anomaly has arisen where formerly excellent agreement between theoretical predictions and experiment in single-top-quark production at the Tevatron is no longer quite as good. Is this indicative of a deeper issue?
Presented by Prof. Zack SULLIVAN on 12 Sep 2017 at 12:15
The Fermi Gamma-Ray Space Telescope lives its maturity as the reference, all-sky survey and all-timing monitoring, mission for the observation of the violent high-energy gamma-ray Universe. This is true for the past data heritage as well as for future perspectives, especially in the rapidly growing science of multi-wavelength and multi-messenger astroparticle physics. The Large Area Tele ... More
Presented by Stefano CIPRINI on 15 Sep 2017 at 18:10
An asymptotic solution to the QCD parton branching equation is derived using the method of Laplace transformation and saddle point approximation. The distribution is applied to charged particle multiplicity distributions in proton-proton collisions at $\sqrt{s} = 0.9, 2.36,$ and $7$ TeV for $|\eta| < 0.5, 1.0, 1.5, 2.0, 2.4,$ and $8$ TeV for $|\eta| < 0.5, 1.0, 1.5,$ as well as $13$ TeV data for $ ... More
Presented by Dr. WEI YANG WANG on 15 Sep 2017 at 12:40
Relativistic heavy-ion collisions provide an optimal test bed to study bulk and collective properties of hot and dense nuclear matter above the QCD critical point where hadrons melt to form a quark-gluon plasma. Simulations of the collisions, which couple relativistic hydrodynamics to microscopic transport models, allow theorists to recreate the full spacetime evolution of the events and determin ... More
Presented by Mr. Scott MORELAND on 14 Sep 2017 at 12:15
The suppression of Y mesons in the hot quark-gluon medium (QGP) versus reduced feed-down is investigated at energies reached at the Relativistic Heavy Ion Collider RHIC and the Large Hadron Collider LHC. Our centrality- and p_T-dependent model encompasses screening, collisional damping and gluodissociation in the QGP. For the Y(1S) ground state it is in agreement with both STAR and CMS da ... More
Presented by Prof. Georg WOLSCHIN on 11 Sep 2017 at 09:25
Session: Flash Talks
We study the interplay of the contribution of bulk and shear viscosities n p-p and p-Pb collisions at LHC energies in the framework of the String Percolation Model which exhibit a similar behavior as in the geometric phase transition given in heavy ion collision is showed for high multiplicities in small collision system. The results show that the bulk viscosity has a relevant contribution to the ... More
Presented by Mr. J. Ricardo ALVARADO GARCÍA on 11 Sep 2017 at 17:45
The calculation of hadronic observables using a combination of Dyson-Schwinger and Bethe-Salpeter equations has developed dramatically in recent years. The method aims at the calculation of hadronic properties from the underlying QCD degrees of freedom, without abandoning the realm of continuum quantum field theories. We report on the most recent calculations of the spectrum and electr ... More
Presented by Dr. Helios SANCHIS ALEPUZ on 13 Sep 2017 at 10:35
Session: Flash Talks
We compute the net electric current generated during a first order electroweak phase transition when fermions transit from the false to the true vacuum. This current is generated by the CP-violating fermion interaction with the Higgs during the phase transition and is quantified in terms of a CP-violating phase in the bubble wall separating the symmetric from the symmetry-broken phases. We comment ... More
Presented by Mr. Jordi SALINAS on 11 Sep 2017 at 17:30
Metastable domains of fluctuating topological charges can change the chirality of quarks and induce local parity violation in quantum chromodynamics. This can lead to observable charge separation along the direction of the strong magnetic field produced in relativistic heavy-ion collisions, a phenomenon called the chiral magnetic effect (CME). A major background source for CME measurements ... More
Presented by Dr. Jie ZHAO on 15 Sep 2017 at 12:15
Collectivity, as interpreted to mean flow of a dense medium in high-energy nucleus-nucleus (A-A) collisions and described by hydrodynamics, has recently been attributed also to smaller collision systems -- p-A and even p-p collisions -- based on certain analysis of LHC data. However, alternative analysis methods reveal that some data features attributed to flows are actually manifestations of mini ... More
Presented by Prof. Thomas TRAINOR on 14 Sep 2017 at 12:40
Observations of long rang azimuthal correlations in small collision systems (p+p/A) have triggered an enormous excitement in the heavy-ion community. However, it is presently unclear to what extent the experimentally observed correlations should be attributed to initial state momentum correlations and/or the final state response to the initial state geometry. In this talk I will provide a brief ov ... More
Presented by Dr. Soeren SCHLICHTING on 15 Sep 2017 at 09:25
We study the relation between the continuum threshold within finite energy sum rules and the trace of the Polyakov loop in the frame of a nonlocal SU(2) chiral quark model, establishing a contact betweem both deconfinement paramenters at finite temperature and chemical potential . In our analysis, we also incorporate the chiral quark condensate as an order parameter for the chiral symmetry restora ... More
Presented by Prof. Marcelo LOEWE on 14 Sep 2017 at 09:50
The High-Altitude Water Cherenkov (HAWC) Observatory is an array of large water Cherenkov detectors sensitive to both gamma rays and hadronic cosmic rays in the energy band between 100 GeV and 100 TeV. HAWC was constructed on Sierra Negra, Puebla, México, at 4100 meters above sea level and began full operation at the end of March 2015. The array consists of 300 water Cherenkov detectors, covering ... More
Presented by Dr. Eduardo DE LA FUENTE ACOSTA on 15 Sep 2017 at 17:45
Direct photon-hadron correlations from photon-jet pairs are an important tool to study jet energy loss and jet modification in Heavy Ion collisions since the direct photon escapes the medium without strong interaction and can act as a control or energy calibrator to the opposing jet in the same event. Due to the large background of meson decay photons from di-jets, measurements are experime ... More
Presented by Justin FRANTZ on 12 Sep 2017 at 16:10
We present results on a study of the dynamics of the formation of nonhomogeneous phases of the chiral transition transition in QCD. The possibility of the formation of a spatially modulated chiral condensate in the final stages of a heavy-ion collision is investigated assuming a Ginzburg-Landau-Langevin time evolution, using a free energy functional motivated by the Nambu—Jona-Lasinio mo ... More
Presented by Prof. Gastao KREIN on 11 Sep 2017 at 16:35
Diffractive phenomena at the LHC are being studied by several collaborations at CERN. In this paper we present our recent results on the deviation from the exponential behavior in elastic proton-proton scattering at low |t| as well as central exclusive resonance production. Although the above phenomena occur in different kinematical regions, they are related e.g. by Regge-factorization. ... More
Presented by Prof. Laszlo JENKVOSZKY on 14 Sep 2017 at 16:00
The electro-magnetic probes have been widely used to study the fundamental properties of hot, dense medium created in heavy ion collisions. I will review most recent experimental results on electromagnetic radiation in hadronic interactions from pp to AA collisions. Future perspectives will also be discussed.
Presented by Dr. Lijuan RUAN on 14 Sep 2017 at 10:15
The ALICE experiment at CERN was designed to study the properties of the strongly-interacting hot and dense matter created in heavy-ion collisions at LHC energies. Smaller collision systems such as proton-proton (pp) and proton-nucleus (p-Pb) provide reference samples for nucleus-nucleus collisions (Pb-Pb) and allow to unveil features attributed to the formation of a deconfined Quark-Gluon Plasma ... More
Presented by Domenico ELIA on 12 Sep 2017 at 15:45
Based on a Hamiltonian approach with in-medium Cornell potential we evaluate the many-body properties of the quark-gluon plasma (QGP) in the nonperturbative regime. The in-medium two-body potential is constrained by lattice-QCD data on the heavy-quark free energy. The equation of state is computed in the Luttinger-Ward-Baym formalism with selfconsistent off-shell propagators and T-matrix. A ... More
Presented by Prof. Ralf RAPP on 12 Sep 2017 at 15:20
In this talk, we will describe the most results concerning exclusive diffractive production from the ATLAS, CMS, LHCb and TOTEM collaborations with and without proton tagging.
Presented by Prof. Christophe ROYON on 15 Sep 2017 at 16:10
This talk will summarize the latest experimental results in using heavy quarks to probe the Quark-Gluon Plasma created at RHIC and LHC. The presentation will include a discussion on the heavy quark production mechanisms, initial state effects in nucleus and final interaction with the hot and dense medium. A part of the talk will be dedicated to recent studies with bound state heavy-quarkonia ... More
Presented by Dr. Cesar Luiz DA SILVA on 14 Sep 2017 at 09:00
Jets in hard parton scatterings in relativistic heavy ion collisions are important probes of the quark-gluon plasma (QGP), a deconfined state of quarks and gluons. Final-state jets are created by the fragmentation of outgoing partons that interact strongly with the produced medium and lose energy. This phenomenon "jet-quenching" was studied using various experimental observables such as inclusive ... More
Presented by Prof. Yen-Jie LEE on 12 Sep 2017 at 10:40
The azimuthal anisotropies of particle yields observed in relativistic heavy ion collisions have been traditionally considered as a strong evidence of the formation on a deconfined quark-gluon plasma produced in these collisions. However multiple recent measurements in $pp$ and $p$/D/He+A collisions show similar features as those observed in A+A Collisions, indicating the possibility of the ... More
Presented by Dr. Soumya MOHAPATRA on 14 Sep 2017 at 11:25
The quark-gluon plasma (QGP) created in high energy collisions of large nuclei (e.g., AuAu or PbPb) has been found to exhibit strong collective behavior as a nearly perfect liquid, which flows with little frictional resistance or viscosity. I will review latest experimental results on collective flow in heavy ion collisions at RHIC and the LHC, and discuss their implications to our understanding o ... More
Presented by Prof. Sandra S. PADULA on 14 Sep 2017 at 13:05
Forward-backward multiplicity correlations have been used to study hadron production mechanisms in electron-positron, proton-proton and more recently in lead-lead collisions. The experimental results and its comparison to different models reveal an incomplete agreement. In this work we present and study of forward backward multiplicity correlations in proton-proton collisions using the PYTHIA ev ... More
Presented by Mr. Edgar DOMINGUEZ ROSAS on 15 Sep 2017 at 09:50
Resume. Multiwire proportional chamber is a conventional technique to study radiation in general, and cosmic rays in particular. To study cosmic rays, it was planned, designed, constructed, characterized, and tested a four channel mini wire chamber, based on two 3 cm X 3 cm X 0.6 cm Aluminum frames, two 3 cm X 3 cm X 0.6 cm plastic frames, two 3 cm X 3 cm X 0.3 cm Aluminum frames, two electronic p ... More
Presented by Dr. Julian FELIX on 15 Sep 2017 at 17:20
The temperature dependence of the gluon condensate is deduced from the Polyakov loop effective potential. It is shown that this approach provides a simple picture for the electric gluon condensate around the deconfinement temperature, showing that it drops to zero in a temperature range which is in good agreement with different pure gauge lattice results.
Presented by Dr. Juan Cristóbal ROJAS on 12 Sep 2017 at 18:35
Recent results on Bose-Einstein correlations will be overviewed, including the identification of the proper variables and the analysis of the shape of second and higher order Bose-Einstein correlations in high energy physics, from e+e- at LEP through pp, pA, AB and AA collisions at RHIC and LHC. One of the emphasized topics will be the ongoing search for Bose-Einstein condensation in high ... More
Presented by Prof. Tamas CSORGO on 11 Sep 2017 at 10:40
The Belle II experiment at the SuperKEKB collider is a major upgrade of the KEK “B factory” facility in Tsukuba, Japan aiming at an increase of the instantaneous luminosity by a factor of 40 to a record-breaking value of $8\times10^{35} \ \mathrm{cm^{-2}s^{-1}}$. Commissioning of the SuperKEKB main ring took place in the first half of 2016 and during summer 2017, first cosmic ray data wa ... More
Presented by Nils BRAUN on 12 Sep 2017 at 17:20
Since a decade, the ultrarelativistic heavy ion collisions (URHIC) community has accumulated strong evidence that a collective state of deconfined but strongly interacting matter is achieved in those collisions, performed both at RHIC or LHC colliders. It is also established that heavy quarks (HQ) created at the initial stage of the URHIC finally stem out with some lack thermalization, which a ... More
Presented by Prof. Pol GOSSIAUX on 14 Sep 2017 at 10:40
Measurements of inclusive and differential top-quark production cross-sections in hadronic final states, including hadronic tau decays, in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented at center of mass energies of 7, 8 and 13 TeV. The inclusive cross-section measurements reach high precision and are compared to other decay modes and the best availabl ... More
Presented by Ms. Serena PALAZZO on 12 Sep 2017 at 09:25
Session: Flash Talks
Fast-moving partons lose energy and momentum along their paths through the QGP. This deposition of energy-momentum creates a disturbance in the medium that can be described using approximations within relativistic hydrodynamics in a defined regime of the QGP evolution. Based on earlier research in this field, where a localized source was used to model the parton energy-momentum in-medium depositio ... More
Presented by Julio César MALDONADO GONZÁLEZ on 11 Sep 2017 at 17:50
In relativistic heavy-ion collisions, a hot medium with a high density of unscreened colour charges is produced. Jets are produced by parton-parton scatterings in the early stages of the collision, and are observed to be attenuated as they propagate through the hot matter. One manifestation of this energy loss is a lower yield of jets emerging from the medium than expected in the absence of medium ... More
Presented by Laura HAVENER on 14 Sep 2017 at 09:25
Beta disintegration is studied in the presence of a magnetic field, which imposes a preferential direction on the emission of neutrinos. We explore the possibility that this anisotropy in neutrino emission can account for observed Pulsar's velocities (kicks). The conditions under which the anisotropic emission of neutrinos (due to the magnetic field present in the system) causes a “kick” of th ... More
Presented by Dr. Daryel MANREZA on 14 Sep 2017 at 17:35
We use the linear sigma model coupled to quarks to compute the effective potential beyond the mean field approximation, including the contribution of the ring diagrams at finite temperature and baryon density. We determine the model couplings and use them to study the phase diagram in the baryon chemical potential-temperature plane and to locate the critical end point.
Presented by Dr. Saul HERNANDEZ on 11 Sep 2017 at 12:40
The latest results on the measurement of the cross sections and couplings of the Higgs boson in ttH production or it's decay to bottom quarks are reported. The ttH production mode is analyzed in H->bb, H->gamgam and multilepton decay modes. The decay H->bb is also searched for in the associated VH and Vector Boson fusion production modes. The results are based pp collision data collected at 13 Te ... More
Presented by Dr. Jose BENITEZ on 12 Sep 2017 at 09:00
The production of prompt isolated photons at hadron colliders provides a stringent test of perturbative QCD and can be used to probe the proton structure. The ATLAS collaboration has performed precise measurements of the inclusive production of isolated prompt photons at a centre-of-mass energy of 13 TeV, differential in both rapidity and the photon transverse momentum. In addition, the integrated ... More
Presented by Dr. Miguel VILLAPLANA on 11 Sep 2017 at 11:50
The measurements of hadronic form factors using the data samples collected with the BESIII detector at BEPCII collider are presented. The cross section of $e^+e^-\to p\bar{p}$ at 12 energies from $2232.4$ to $3671.0$ MeV are measured, the electromagnetic form factor is deduced, and the ratio $|G_{E}/G_{M}|$ is extracted by fitting the polar angle distribution. The cross section of $e^+e^-\to\pi^+\ ... More
Presented by Prof. Haiming HU on 11 Sep 2017 at 15:20
We present results on measurements of (1) characteristics of events with jets, from jet-charge over investigations of shapes to jet mass distributions. The measurements are compared to theoretical prediction including those matched to parton shower and hadronization; (2) Multi-differential jet cross sections over a wide range in transverse momenta from inclusive jets to multi-jet final states. We ... More
Presented by Ms. Anterpreet KAUR on 11 Sep 2017 at 11:25
The Quark-Gluon Plasma (QGP) is created in high energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). This medium is transparent to electromagnetic probes but nearly opaque to colored probes. Hard partons produced early in the collision fragment and hadronize into a collimated spray of particles called a jet. The partons lose energy a ... More
Presented by Dr. Christine NATTRASS on 15 Sep 2017 at 10:40
The elastic, electromagnetic form factors are fundamental observables that describe the internal structure of protons, neutrons, and atomic nuclei. Jefferson Lab in the United States has nearly completed the 12 GeV Upgrade that will open new opportunities to study the form factors. A campaign to measure all four nucleon form factors (electric and magnetic ones for both proton and neutron) has ... More
Presented by Dr. Gerard GILFOYLE on 12 Sep 2017 at 17:45
Measurements of the Drell-Yan production of $W$ and $Z/\gamma$ bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center-of-mass energies of 7 TeV. The measurements are performed for $W^+$, $W^-$ and $Z/\gamma$ bosons integrated and as a function of t ... More
Presented by Alessandro LAPERTOSA on 11 Sep 2017 at 14:55
In this talk I will review recent results about the cosmic ray spectrum and chemical composition in the $10^{15}$-$10^{18}$ eV energy range. At lower edge of this energy range we are quite confident that cosmic rays are mainly of galactic origin, while at energies greater than those covered in the same energy interval we have strong hints of an extra-galactic origin of the radiation. Ind ... More
Presented by Andrea CHIAVASSA on 14 Sep 2017 at 16:45
We study the modification of the jet structures in the quark-gluon plasma (QGP) fluid including the effect of the medium response. The jet structures in heavy ion collisions are significantly modified by the processes involving strong interactions with the QGP fluid, i.e., collisional energy loss, transverse-momentum broadening, and induced parton radiation. The energy and momentum are deposit ... More
Presented by Yasuki TACHIBANA on 15 Sep 2017 at 10:15
Recently the CERN ALICE experiment, in its dedicated cosmic ray run, observed muon bundles of very high multiplicities, thereby confirming similar findings from the LEP era at CERN (in the CosmoLEP project). Originally it was argued that they apparently stem from the primary cosmic rays with a heavy masses. We propose an alternative possibility arguing that muonic bundles of highest mu ... More
Presented by Dr. Maciej RYBCZYNSKI on 15 Sep 2017 at 16:55
Session: Flash Talks
Measurements of hadron production in p-Pb collisions serve as reference to help disectangle initial and final-state effects for the hadron suppresion observed at intermediate $p_T$ in Pb-Pb collisions. Moreover, the measurement of neutral mesons ($\pi^{0}$ and $\eta$) is important to estimate the background in the direct photon analysis. ALICE has measured $\pi^{0}$ and $\eta$ mesons via their t ... More
Presented by Pedro GONZALEZ ZAMORA on 11 Sep 2017 at 17:20
The BABAR Collaboration has an extensive program studying hadronic cross sections in low-energy e+e- collisions, accessible through the selection of events with initial-state photon radiation. The measurements allow significant improvements in the precision of the standard model prediction for the muon anomalous magnetic moment. Recent results on the pi+pi-pi0pi0 final state and on KKpipi final st ... More
Presented by Prof. Bill GARY on 12 Sep 2017 at 09:50
We study the thermomagnetic properties of the strong coupling constant $G$ and quark mass $M$ entering the Nambu–Jona-Lasinio model. For this purpose, we compute the quark condensate and compare it to lattice QCD (LQCD) results to extract the behavior of $G$ and $M$ as functions of the magnetic field strength and temperature. We also study the correlation length between test quarks with the same ... More
Presented by Dr. Alfredo RAYA on 13 Sep 2017 at 19:00
Meson photoproduction is an important tool in the study of baryon resonances. The spectrum of broad and overlapping nucleon excitations can be greatly clarified by use of polarization observables. The N* program at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) includes experimental studies with linearly- and circularly-polarized tagged-photon beams, longitudinally- and transver ... More
Presented by Prof. Steffen STRAUCH on 11 Sep 2017 at 16:10
The study of heavy flavor production in proton-nucleus and nucleus-nucleus collisions is a sensitive probe of the hot and dense matter created in such collisions. Installation of silicon vertex detectors in the PHENIX experiment, and increased performance of the BNL RHIC collider allowed collection of large amount of data on heavy flavor production in small colliding systems. In this ... More
Presented by alexandre LEBEDEV on 11 Sep 2017 at 09:00
Session: Flash Talks
The Multi-Purpose Detector (MPD) is designed to study heavy ion collisions in the Nuclotron-based Ion Collider fAcility (NICA), currently under construction at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The goal is to study the phase diagram of strongly interacting matter at high baryon density. At the design luminosity, the event rate in the MPD interaction region is ... More
Presented by Mr. Heber ZEPEDA on 11 Sep 2017 at 18:00
Heavy-ion collisions can generate extremely hot matter and also extremely strong magnetic fields and fluid vorticity. Once coupled to chiral anomaly, the magnetic fields and fluid vorticity can induce a variety of novel transport phenomena, including the chiral magnetic effect, chiral vortical effect. Some of them require the environmental violation of parity and charge conjugation symmetry, ... More
Presented by Mr. Xu-Guang HUANG on 11 Sep 2017 at 10:15
In this talk, we present the results of photon production at early times in semi-central relativistic heavy-ion collisions from non-equilibrium gluon fusion induced by a magnetic field. The calculation accounts for the main features of the collision at these early times, namely, the intense magnetic field and the high gluon occupation number. The photon yield from this process is an excess over ca ... More
Presented by Dr. Luis HERNANDEZ on 11 Sep 2017 at 12:15
The exclusive photoproduction of upsilon states is investigated in the context of ultra-peripheral collisions at the LHC energies. Predictions are presented for their production in proton-proton, proton-nucleus and nucleus-nucleus collision at the energies available at the LHC run 2. The theoretical framework considered in the analysis is the light-cone color dipole formalism, which includes consi ... More
Presented by Dr. Magno MACHADO on 14 Sep 2017 at 14:45
The 2015 US Nuclear Physics Long-Range Plan endorsed the realization of an Electron- Ion Collider (EIC) as the next large construction project in the United States. With its high luminosity ( > 1033 cm−2s−1), wide kinematic reach in center-of-mass-energy (45 GeV to 145 GeV) and high lepton and proton beam polarization, the EIC is an unprecedented opportunity to reach new frontiers in ou ... More
Presented by Dr. Salvatore FAZIO on 13 Sep 2017 at 09:00
One of the main goals of the Large Hadron Collider is to find signatures of physics Beyond the Standard Model of particle physics. One way to do this is by studying with high precision the interactions of the Standard Model. In this talk, we address the discovery potential of New Physics in the exclusive channel pp $\rightarrow$ p X p which relies on the general purpose detectors at the Large Hadr ... More
Presented by Cristian BALDENEGRO BARRERA on 14 Sep 2017 at 15:10
Heavy quarks (charm and beauty) are produced in the initial stages of the collisions due to their large masses. This allows them to probe the full evolution of the system, interacting with the Quark-Gluon Plasma (QGP) created in high-energy heavy-ion collisions. In p-Pb collisions, Cold Nuclear Matter effects can modify the heavy-flavour production spectra at low momentum. The study of small ... More
Presented by Mr. Henrique Jose CORREIA ZANOLI on 15 Sep 2017 at 11:25
Session: Flash Talks
We compute the production of prompt photons and the $v_2$ harmonic coefficient in relativistic heavy-ion collisions induced by gluon fusion in the presence of an intense magnetic field, during the early stages of the reaction. The calculations take into account several parameters which are relevant to the description of the experimental transverse momentum distribution, and elliptic flow for RHIC ... More
Presented by Mr. Jorge David CASTAÑO YEPES on 11 Sep 2017 at 17:55
The azimuthal anisotropies of particle yields observed in relativistic heavy-ion collisions have been traditionally considered as a strong evidence of the formation on a deconfined quark-gluon plasma produced in these collisions. However multiple recent measurements from the ATLAS Collaboration in $pp$ and $p$+Pb systems show similar features as those observed in A+A collisions, indicating t ... More
Presented by Dr. Adam TRZUPEK on 14 Sep 2017 at 11:50
The Pierre Auger Observatory is the largest cosmic ray detector ever built. It was designed to detect the highest energy particles in the Universe, and it has been taking data since 2004. Our published results range from the measurement of the flux suppression at the highest energies to limits on 1000-PeV neutrinos, from limits on the flux of EeV neutrons from the Galaxy to the measurement of the ... More
Presented by Prof. Miguel MOSTAFA on 14 Sep 2017 at 17:10
Over the last decade in relativistic heavy-ion collisions, the modification of hard QCD jets due to their passage through the Quark Gluon Plasma (QGP) has turned from a discovery to a precision tool to study the internal structure of the QGP. We will focus on a variety of issues related to the use of this tool as a probe of the plasma. This will be followed by a brief discussion of some of the ... More
Presented by Dr. Abhijit MAJUMDER on 12 Sep 2017 at 16:35
The formation of a Quark-Gluon Plasma (QGP) in heavy-ion collisions is well established by numerous measurements and their comparison to hydrodynamic models. However, in recent years, a growing number of results in small collision systems show similar properties as peripheral Pb--Pb collisions. This raises the question of whether small systems behave collectively or not, which is one of the most d ... More
Presented by Ms. Katarina GAJDOSOVA on 12 Sep 2017 at 14:55
We construct small-x evolution equations for the quark and gluon helicity distributions. The equations present a new type of evolution, resumming double logarithms of energy, that is, powers of $\alpha_s \, \ln^2 (1/x)$. We solve the equations both analytically and numerically and obtain the following small-x asymptotics for the quark and gluon helicity distributions: $\Delta q \sim \lef ... More
Presented by Prof. Yuri KOVCHEGOV on 12 Sep 2017 at 11:25
I will review recent LHC results on soft diffraction, in particular elastic scattering, total cross-section, single diffraction and double diffraction.
Presented by Dr. Jan KASPAR on 15 Sep 2017 at 15:20
The large transverse momentum distributions of particles observed in all LHC experiments exhibit a quasi-power-like behavior following the two-parameter Tsallis distribution with a scale factor T and nonextensivity q. Such distributions can originate from different dynamical mechanisms. However, looking at the ratios of the measured cross-sections to their phenomenological power-like fits, R = f_ ... More
Presented by Prof. Grzegorz WILK on 11 Sep 2017 at 09:50
The study of the heavy ion collisions is of great interest in high energy physics due to expected phase transition from the nucleons to the quark gluon plasma. But to have a full picture of the effect there is a lack of experimental data in the low energy region for the nuclei-nucleus collisions. The goal of the NICA project at JINR is to cover the energy range from 2 GeV/n to 11 GeV/n ... More
Presented by Dr. Oleg ROGACHEVSKIY on 11 Sep 2017 at 13:05
We study the behavior of strongly interacting matter under an external constant magnetic field in the context of non-local chiral quark models that incorporate coupling to the Polyakov loop. We find that at zero temperature the behavior of the quark condensates shows the expected magnetic catalysis effect, our predictions being in good quantitative agreement with lattice QCD results. On th ... More
Presented by Prof. Norberto SCOCCOLA on 12 Sep 2017 at 19:25
Session: Flash Talks
We present a study of the event by event mean transverse momentum fluctuations in high multiplicity pp and p-Pb collision systems at LHC energies in the framework of the String Percolation Model as a function of multiplicity. We found that data can be naturally described by the clustering of color sources that take place in the small collision systems in a similar manner as it does in heavy ion co ... More
Presented by Mrs. Cristal ROBLES JACOBO on 11 Sep 2017 at 17:25
In high energy collisions, partons produced in the initial stage undergo the multiple interaction and yield a collective motion as a whole. Recently, several questions came up including how small the system can be for producing the collectivity, and how far in rapidity the collectivity extends. PHENIX has measured the particle flow in p/d/A+A collisions over several energies as well as over ... More
Presented by Ms. Seyoung HAN on 13 Sep 2017 at 11:00
Studies of charge-dependent azimuthal correlations for the same- and opposite-sign particle pairs are presented in PbPb collisions at 5 TeV and pPb colisions at 5 and 8.16 TeV, with the CMS experiment at the LHC. The azimuthal correlations are evaluated with respect to the second- and also higher-order event planes, as a function of particle pseudorapidity and transverse momentum, and event mu ... More
Presented by Mr. Zhoudunming Kong TU on 15 Sep 2017 at 11:50
High pT hadrons are mainly coming from the fragments of the hard scattered partons produced at the initial stage of the collisions. The suppression of the yield of high pT hadrons was one of the key observables for declaring the discovery of the QGP at RHIC. The observation of the collective flow of the particles in p+Pb collisions at LHC inspired the field and the experiments at RHIC p ... More
Presented by Dr. Takao SAKAGUCHI on 12 Sep 2017 at 10:15
Session: Flash Talks
The KASCADE-Grande observatory was a ground-based air shower array devoted to the study of the energy and composition of cosmic rays with energies from 1 PeV to 1 EeV. The experiment consisted of different detector systems which allowed the simultaneous measurement of distinct components of the air showers (EAS), such as the muon content. We study the total muon number and the lateral density dist ... More
Presented by Mr. David RIVERA on 11 Sep 2017 at 18:05
The KASCADE-Grande observatory was a ground-based air shower array devoted to the study of the energy and composition of cosmic rays with energies from 1 PeV to 1 EeV. The experiment consisted of different detector systems which allowed the simultaneous measurement of distinct components of the air showers (EAS), such as the muon content. In this contribution, we study the total muon number and th ... More
Presented by Dr. Juan Carlos ARTEAGA VELAZQUEZ on 14 Sep 2017 at 18:00
We discuss theoretical approaches to form factors in heavy-meson decays, e.g. weak decay constants, transition form factors and effective heavy-to-light meson couplings, which are hadronic expressions of nonperturbative QCD. After motivating their origin in QCD factorization and heavy quark effective theories, we retrace their evolution from earlier quark-model calculations to nonperturbative QCD ... More
Presented by Prof. Bruno EL-BENNICH on 12 Sep 2017 at 18:10
I discuss the fragmentation region at very high energies. Due to the mismatch of the saturation momenta of the target and projectile, there is a parametric difference between the energy density and multiplicity density of produced particles dependence upon saturation momenta. This parametric difference allows one to discriminate between thermalized and non-thermalized systems by measuring ... More
Presented by Prof. Larry MCLERRAN on 11 Sep 2017 at 15:45
The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is the world's only polarized proton collider with center-of-mass energies up to 500 GeV and polarizations of about 60% for each proton beam and the the worlds most versatile collider, able to collide different species over an extremely wide kinematic range. It provides unique opportunities to study the spin structure in ... More
Presented by Dr. Elke-Caroline ASCHENAUER ELKE-CAROLINE on 13 Sep 2017 at 09:25
Consider the production of a hard dijet in high-energy DIS with large average transverse momentum \vec{P} = (\vec{k1}-\vec{k2})/2 and small(er) momentum imbalance \vec{q} = \vec{k1}+\vec{k2}. The cross section involves a sum of an isotropic contribution proportional to the conventional Weizsaecker-Williams gluon distribution and of a contribution proportional to cos(2phi) times the WW distribution ... More
Presented by Adrian DUMITRU on 12 Sep 2017 at 12:40
Session: Flash Talks
Within the Dyson-Schwinger equations (DSEs) approach, we study the nucleon to its parity partner, N*(1535), transition form factor. This framework demands to solve the three-particle bound state equation equation, Faddeev Equation. A sophisticated diquark picture is employed in order to expedite the computation of this transition. Several intermediate diquark transitions are required to obtain the ... More
Presented by Khépani RAYA on 11 Sep 2017 at 17:35
We evaluate the impact of recent developments in hadron phenomenology on constraining the electroweak effective theory Lagrangian beyond the standard model. We focus, in particular, on the scalar and tensor components which can be measured in precision neutron beta decay. We show how a class of new observables, the chiral-odd generalized parton distributions, along with the extraction of the t ... More
Presented by Dr. Aurore COURTOY on 12 Sep 2017 at 11:50
We use the spinor helicity formalism to calculate the cross section for production of three partons of a given polarization in Deep Inelastic Scattering (DIS) off proton and nucleus targets at small Bjorken x. The target proton or nucleus is treated as a classical color field (shock wave) from which the produced partons scatter multiple times. The resulting expressions are used to study azimuthal ... More
Presented by Dr. Martin HENTSCHINSKI on 14 Sep 2017 at 15:35
As was pointed out long ago by Mueller and Tang, the BFKL hard Pomeron, at finite momentum transfer, can be investigated at hadron colliders by looking for the exclusive processes where the only observed radiation are two jets detected far apart in rapidity. The absence of any additional emission over a large rapidity region suggests that the color-singlet exchange contributes substantially t ... More
Presented by Dr. Timothy RABEN on 15 Sep 2017 at 15:45
Transverse Momentum Dependent Functions (TMDs) encode essential information about both the structure of nucleons and hadronization processes. They cannot be calculated from first principles, instead, one must determine them via phenomenological analyses. Recent multidimensional data in semi-inclusive deeply inelastic scattering (SIDIS) has made it evident that several theoretical issues must be ... More
Presented by Dr. Osvaldo GONZALEZ on 13 Sep 2017 at 09:50
Session: Flash Talks
We study the QCD phase diagram using the linear sigma model coupled to quarks (LSMq). We compute the effective potential at finite temperature and baryon density up to ring diagrams order. We show that, provided the parameters for the pseudo-critical temperature (for $\mu^B=0$) and critical chemical potential $\mu_c^B$ (for $T=0$) are taken as $T_c\simeq 155$ MeV and $\mu_c^B\simeq 1$ GeV, togethe ... More
Presented by Mr. José FLORES on 11 Sep 2017 at 17:40
Vector boson-tagged jet production in collisions of heavy nuclei opens new opportunities to study parton shower formation and propagation in strongly interacting matter. It has been argued to provide a golden channel that can constrain the energy loss of jets in the quark-gluon plasma created in heavy ion reactions. We present theoretical results for isolated photon-tagged and $Z_0$ boson-tagged j ... More
Presented by Dr. Vitev IVAN on 15 Sep 2017 at 09:00
Two-particle correlations have proven to be a robust tool which allow the exploration of many physics phenomena present in high-energy particle collisions. In this talk we would like to focus on two techniques, namely femtoscopy and angular correlations, covering their most recent results from the ALICE experiment. Femtoscopic correlations which arise from quantum statistics and final-state ... More
Presented by Dr. Łukasz GRACZYKOWSKI on 15 Sep 2017 at 13:05