2 min pitches of the panellists
In this work we report the first results on $K^{*}(892)^{\pm}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 5.02 TeV with the ALICE detector. The hidden strangeness $\phi$-meson is reconstructed at mid-rapidity via its hadronic decay channel $\phi \rightarrow$ K$^{+}$K$^{-}$, by employing different techniques, without and with kaon identification using the information from the...
Angular correlations of heavy-flavour hadron decay electrons with charged particles in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV with the ALICE Detector
Henrique Zanoli on behalf of the ALICE Collaboration
Two-particle correlations in azimuth and pseudorapidity are used to explore the properties of the hot and dense medium created in heavy ion collisions by studying collective...
Measurements of azimuthal correlations can be used to probe the anisotropy of produced particles, and are therefore sensitive probes of the initial conditions of the collision.
Moreover, the measurement of anisotropy in p-Pb collisions may provide additional insights into the possible collectivity
in this small system originally motivated by the measurements of multi-particle azimuthal...
Different aspects of chiral phenomena are considered on the basis of comparison of generalized thermodynamic distribution function and quantum-field calculation of one-loop triangle diagram. The consequences for particle polarization in heavy ion collisions are discussed.
Correlation femtoscopy allows one to measure the space-time characteristics of particle production in relativistic heavy-ion collisions due to the effects of quantum statistics and final state interactions. The main features of the femtoscopy measurements at top RHIC and LHC energies are considered as a manifestation of strong collective flow and well interpreted within hydrodynamic models...
We investigate the shear viscosity ($\eta$) and electrical conductivity ($\sigma_{\rm{el}}$)
of the anisotropic quark-gluon plasma (QGP) medium.
Relativistic Boltzmann kinetic equation has been solved
in the relaxation time approximation to calculate the shear viscosity and electrical conductivity. We use the quasiparticle model to estimate these transport coefficients and discuss the...
The study of hadronic resonances plays an important role both in elementary and in heavy-ion collisions as it can provide information about strangeness production and the hadronic phase of the system. Since the lifetimes of short-lived resonances are comparable with the lifetime of the fireball formed in heavy-ion collisions, regeneration and rescattering effects can modify the measured yield...
Heavy quarks (charm and beauty) are unique probes used to understand the properties of the QCD medium produced in ultra-relativistic heavy-ion collisions. Due to their large masses, they are created in the early stages of the collisions and experience the full evolution of Quark-Gluon Plasma (QGP). They interact with its consitutents and lose energy as they travel through the medium. Heavy...
The study of the J/$\psi$ production in pp collisions provides important information on perturbative and non-perturbative quantum chromodynamics. The production of the heavy-quark pair can be described perturbatively while its hadronisation into quarkonium state is a non-perturbative process. These processes are not fully understood and additional experimental data are necessary to further...
The lifetimes of short-lived hadronic resonances are comparable to the one of the hadronic phase of the medium produced in high-energy collisions. Thus, these resonances are sensitive to the re-scattering and regeneration processes in the time interval between the chemical and kinetic freeze-out, which might affect the resonance yields. The measurements in pp collisions are used as a...
In the high-energy heavy-ion physics community the FORTRAN based HIJING Heavy Ion Jet Interaction Generator code is commonly used, originally developed by Xin-Nian Wang and Miklos Gyulassy [1]. Although it was intended to describe the heavy-ion collisions occurring at RHIC energies, it has still many applications with todays higher collision energies. However, the technological advancement...
Measurements of open heavy-flavour production in p--Pb collisions at the Large Hadron Collider (LHC) allow the study of cold-nuclear matter effects, such as shadowing, $k_T$ broadening and initial-state energy loss. Heavy quarks (charm and beauty) are a valuable probe for the Quark-Gluon Plasma created in Pb--Pb collisions, since they are produced in hard scattering processes in the initial...
Measurements of identified particle production as a function of the event multiplicity in proton-proton (pp) and proton-nucleus collisions have recently gained interest for the investigation of particle production mechanisms in small systems and how they relate to those in the larger system created in nucleus-nucleus collisions.
In particular, recent results reported by the ALICE Collaboration...
Measurements of particle production in high-multiplicity pp collisions are crucial for the understanding of the collective-like features observed in small systems and reminiscent of those present in heavy-ion collisions. The ALICE detector, with its excellent tracking and particle identification capabilities, provides unique possibilities for the systematic study of light-flavour hadrons at...
Аnisotropic flow presents a unique insight into heavy ion collision physics. The presented poster reveals the prospects of studying elliptic flow at the NICA/MPD facility through the UrQMD model.
Presented are results on elliptic flow for simulated and reconstructed hadrons at the planned NICA energy range.
We report on the results on the dynamical modelling of cluster formation with the new combined PHQMD+FRIGA model at Nuclotron and NICA energies. The FRIGA clusterisation algorithm, which can be applied to the transport models, is based on the simulated annealing technique to obtain the most bound configuration of fragments and nucleons. The PHQMD+FRIGA model is able to predict isotope yields...
Knowing the initial geometry and fluctuations in heavy-ion collisions has recently been shown to have important consequences on interpreting the data from the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) experiments. It is also believed that measurement of higher order flow coefficients and their fluctuations can substantially improve the constraints on
the...
Since firstly proposed by C. Tsallis, the q-non-extensive statistics has been of great interest both experimentally and theoretically. One of the most important applications is the non-extensive effects on the transverse momentum (pT) spectra of both strange and non-strange particles in heavy-ion collisions, where it shows a power-law tail for the large pT range.
To clarify not only the...
Bottomonium are produced in the heavy ion collisions and their production is modified compared with elementary collisions. This modification in the production of bottomonia happens due to the presence of hot and dense QCD matter, named as quark-gluon plasma (QGP) formed in ultra relativistic heavy ion collisions. We
present here a comprehensive model based on color screening, collisional...
“PARTICLE STATES” OF LATTICE QCD
Athanasios S. Kapoyannis and Apostolos D. Panagiotou
Nuclear & Particle Physics Section
Department of Physics
University of Athens, Greece
The results from HI collisions at RHIC and LHC indicate that the quark-gluon state formed is a strongly interacting one. Hagedorn had suggested that a strongly interacting system can be equivalently described as a system...
Heavy quarks have been considered valuable probes of the quark-gluon plasma (QGP). It has been found that heavy quarks propagating through a hot and dense QGP lose energy and develop flow. The interacting strength between the heavy quarks and medium ($\hat{q}/D_s$), although not directly measurable, can be estimated by comparison of model calculations with experimental observables. Currently,...
One of the most exciting and puzzling observations in ultrarelativistic
p+A reactions is the fairly large harmonic flow (such as v2(pT) and
v3(pT) coefficients). On one hand, the flow seems to be consistent with
hydrodynamic simulations [1], suggesting a high degree of thermalization
even in such very small collision systems. On the other hand, several
non-thermal mechanisms can also...
The study of hypernuclei in relativistic ion collisions open new
opportunities for nuclear and particle physics. The main processes
leading to the production of hypernuclei in these reactions are
(1) the disintegration of large excited hyper-residues (target-
and projectile-like), and (2) the coalescence of hyperons with other
baryons into light clusters. We use the transport, coalescence...
In hydrodynamic approach to heavy ion collisions, hadrons with nonzero spin produced out of the fluid can acquire polarization via spin-vorticity thermodynamic coupling mechanism [1]. The hydrodynamical quantity steering the polarization is the thermal vorticity, that is minus the antisymmetric part of the gradient of four-temperature field $\beta^\mu=u^\mu/T$.
Based on this idea, it has been...
Correlation measurements, such as the anisotropic flow, constrain the kinematic ($\eta/s$) and bulk ($\zeta/s$) viscosity of the quark-gluon plasma created in heavy-ion collisions, and give insight into the hadronization mechanisms. Particle production mechanisms can also be studied via other correlation techniques that can statistically separate the hadron production associated with a...
We present a new derivation of the heavy quark diffusion coefficient in a strongly-coupled plasma using the AdS/CFT correspondence. Our main result is that, unlike some previous calculations, our diffusion coefficient does not increase with heavy quark velocity: we find that the effect of momentum fluctuations smoothly interpolates between light and heavy flavors. Taking our diffusion...
The production and properties of $K^+$, $K^-$ and $\phi$ in cold nuclear matter generated in pion-nucleus reactions ($\pi^- + A$, $A = C, W$) at $p_{\pi^-}= 1.7$~GeV/c has been investigated with the HADES setup at SIS18/GSI.
Of particular interest is the $K^-$ absorption in nuclear matter which should be driven by strangeness exchange processes on one ($K^- N\rightarrow Y\pi$) or more nucleons...
The multiplicity dependence of heavy flavour production in pp-collisions at LHC energies is studied in the framework of the multi-pomeron exchange model [1-3].
The model is based on the introducing the string collectivity effects in pp collisions, which modifies the bulk multiplicity and transverse momenta, leading to non-trivial pt-n correlation. The string collectivity strength parameter is...
The primary goal of relativistic heavy-ion collisions is to seek and characterize a new state of nuclear matter, called the quark-gluon plasma (QGP), where quarks and gluons are deconfined due to the high temperature and energy density achieved in such collisions. Measurements of invariant yield of strange hadrons can provide information about the particle production mechanism and transport...
Quarkonia are mesons formed of either a charm and anti-charm quark pair ($\rm{J}/\psi$, $\psi(2S)$), or a beauty and anti-beauty quark pair ($\Upsilon$(1S), (2S) and (3S)). In high-energy hadronic collisions such as those delivered by the LHC between 2010 and 2016, quarkonium production results from the hard scattering of two gluons in a process which occurs very early in the collision...
Event-by-event elliptic flow harmonic distributions $p(v_{2})$ are measured in PbPb collisions at $\sqrt{s_{NN}} = 5.02$~TeV using the CMS detector for the integrated $p_{T}$ range $0.3 < p_{T} < 3.0$~GeV/$c$ and pseudorapidity range $\left| eta \right|<1.0$. In order to gain insight on the nature of the initial geometry fluctuations, cumulant flow harmonics are calculated from the moments of...
The availability at the LHC of the largest collision energy in pp collisions allows a significant advance in the measurement of $J/\psi$ production as function of event multiplicity. The interesting relative increase observed with data at the LHC at $\sqrt{s} = 7$ TeV and at RHIC at $\sqrt{s} = 200$ GeV is studied now at unprecedented multiplicities for pp collisions. The newest measurement...
The measurement of heavy flavour production and collective flow is a powerful tool to study the properties of the high-density QCD medium created in heavy-ion collisions as heavy quarks are sensitive to the transport properties of the medium and may interact with the QCD matter differently from light quarks. In particular, the comparison between the nuclear modification factors (RAA) of light-...
The measurement of $\phi$ mesons provides a unique and complimentary method for exploring properties of the hot and dense medium created in the relativistic heavy ion collisions. It has a relatively small hadronic interaction cross section and is sensitive to the increase of strangeness (strangeness enhancement), a phenomenon associated with soft particles in bulk matter. Measurements in the...
Two-particle correlations as a function of $\Delta\eta$ and $\Delta\varphi$ are used in all collision systems to study a wide range of physical phenomena. Examples include the collective behaviour of the QGP medium, jets, quantum statistics or Coulomb effects, conservation laws, and resonance decays.
In this talk, we report measurements of the correlations of identified particles and their...
We present new results on J/psi production in p-Pb collisions, using the data collected in 2016 by LHCb at 8 TeV nucleon-nucleon center-of-mass energy. The LHCb experiment has the unique property to study heavy-ion interactions in the forward region (pseudorapidity between 2 and 5) with a fully instrumented detector. Both forward and backward rapidities are covered thanks to the possibility of...
Quantum Chromodynamics calculations predict that under sufficiently high temperature or energy density nuclear matter undergoes a phase transition from hadrons to a state of deconfined quarks and gluons, the Quark-Gluon Plasma. The properties of this novel state of matter have been extensively studied in high-energy nuclear collisions at RHIC.
Two-particle correlations at small relative...
The energy loss of jets in heavy-ion collisions is expected to depend on the mass and flavor of the initiating parton. Thus, measurements of jet quenching with identified partons place powerful constraints on the thermodynamic and transport properties of the hot and dense medium. Furthermore, recent results that constrain the jet production mechanism will shed additional light on the...
Anisotropic flow ($v_n$) measurements can provide important constraints for initial state models and for precision extraction of the temperature dependence of the specific shear viscosity $\eta/s$. Recent STAR measurements for rapidity even dipolar flow $v^{even}_1$ confirm the important influence of momentum conservation, as well as the characteristic dependencies on $\sqrt{s_{NN}}$ ,...
The study of energy and multiplicity dependence of hadron production in proton-proton (pp) collisions provides a powerful tool to understand similarities and differences between small and large colliding systems. In this talk we present new mid-rapidity measurements of the $p_\mathrm{T}$ distributions and yields of unidentified charged hadrons as well as of pions, kaons, protons, K$^{0}_{\rm...
Heavy flavor quarks, owing to their large masses, are predominantly produced through initial hard scatterings in heavy-ion collisions and thus are ideal probes to study the properties of the strongly coupled Quark Gluon Plasma (sQGP) also produced in these collisions. For example, study of the heavy flavor anisotropic flow can help understand the nature of the interactions between heavy quarks...
We study the $\Lambda_c/D$ ratio and $p/\phi$ at RHIC and LHC within a realistic implementation of coalescence model.
The evolution of the partonic stage is described by the relativistic Boltzmann equation tuned at a fixed shear-viscosity to entropy-density ratio $\eta/s$ and a realistic equation of state.
Such an approach recovers the universal features of the ideal hydrodynamics.
In a...
Quantum Chromodynamics predicts the occurrence of a phase transition from the hadronic matter to a plasma of deconfined quarks and gluons (Quark-Gluon Plasma) at extreme conditions of temperature and energy density. Ultrarelativistic heavy-ion collisions provide the means to study this phase of matter in the laboratory.
Strangeness production is a key tool to understand the properties of the...
The recent BES data of the energy dependent $κσ^2$ for net protons in Au+Au collisions presented large deviations from the statistical baselines at lower collision energies, and non-monotonic behavior at around 20 GeV, which indicates possible signals for the existence of the QCD critical point [1].
In our recent paper [2], we introduce a freeze-out scheme to the dynamical models near the...
Azimuthal anisotropies such as the elliptic flow $v_2$ are important tools for the study of the properties of the quark-gluon plasma (QGP). Recent studies with parton transport models suggest [1,2] that most parton $v_2$ comes from the anisotropic escape of partons, not from the hydrodynamic flow, even for semi-central Au+Au collisions at $\sqrt {s_{NN}}=200$ GeV. In this talk we will study...
Open heavy-flavour mesons are a unique tool to study and characterize the properties of the Quark-Gluon Plasma (QGP), formed in heavy-ion collisions at high energy. Given their large masses, heavy quarks are produced in the initial stages of the heavy-ion collisions, and therefore they experience the whole system evolution, loosing energy interacting with the medium constituents. Thus, the...
Fluid dynamical fluctuations drive a system constantly out of equilibrium in connection with dissipative properties such as shear and bulk viscosity. The interaction of the fluctuations leads to a renormalization in the equation of state and in the transport coefficients. These effects are particularly important near phase transitions and in small systems. In an era of the high-precision...
Heavy-flavour (charm and beauty) production provides relevant information to understand the strongly interacting medium, Quark-Gluon-Plasma (QGP), formed in heavy-ion collisions at ultra-relativistic energies. Heavy quarks are produced primarily in the initial hard partonic interactions, and they propagate through the QGP. A strong suppression of heavy-flavour hadron production has been...
The results on the production of strange and multi-strange hadrons ($K_{0}^{S}$, $\Lambda$, $\Xi$ and $\Omega$) measured with ALICE in Pb-Pb collisions at the top LHC energy of $\sqrt{s_{\rm NN}}~=~5.02~TeV$ are reported.
Thanks to its excellent tracking and particle identification capabilities, ALICE is able to measure weakly decaying particles through the topological reconstruction of the...
We study subthreshold \Xi production in p+A collisions using a BUU type transport code. We propose new \Xi creation mechanisms in two-step processes via hyperon-nucleon collisions. Our calcultions are compared with results by the HADES (GSI, Darmstadt) experiment.
Charmonium states, such as the J/$\psi$ and $\psi$(2S) mesons, are excellent probes of the deconfined state of matter, the Quark-Gluon Plasma (QGP). The understanding of charmonia production in PbPb collisions requires the inclusion of many phenomena, such as dissociation in the QGP and statistical recombination, on top of cold nuclear matter effects (modifications of nPDFs, initial-state...
Supervised learning with a deep convolutional neural network is used to identify the QCD equation of state (EoS) employed in relativistic hydrodynamic simulations of heavy-ion collisions. The final-state particle spectra \rho(p_T,\Phi) provide directly accessible information from experiments. High-level correlations of \rho(p_T,\Phi) learned by the neural network act as an "EoS-meter",...
Studies of particle yields and azimuthal correlations for inclusive and identified charged particles are presented in small collision systems of pp and pPb at the LHC with the CMS detector. Charged pions, kaons, and protons are identified via their energy loss in the CMS silicon tracker. The pT spectra and integrated yields are studied as a function of multiplicity and center-of-mass energies....
Identified particle spectra provide an important tool for understanding the particle production mechanism and the dynamical evolution of the medium created in relativistic heavy ion collisions. Studies involving strange and multi-strange hadrons, such as $K^0_S$, $\Lambda$, $\Xi^-$, and $\Omega^-$, carry additional information since there is no net strangeness content in the initial colliding...
2 min pitches of the panellists:
J. Steinheimer, F. Becattini, E. Brakovskaya, L. Tolos, D. Cabrera
The main physics goal of the NA61/SHINE ion program is the study of the properties of the onset of deconfinement and the search for signatures of the critical point of strongly interacting matter. These goals are pursued by performing an energy and system size scan.
In this talk recent analysis results of Ar+Sc and Be+Be interactions at SPS energies are discussed. Rapidity and transverse mass...
The study of the nuclear modification factor and the forward/backward
asymmetry in p-Pb collisions at $\sqrt(s_{NN})$=5 TeV is extended to
the $\Lambda_c$ baryon, providing the first measurement of charmed
baryon production in pA collisions. The result is compared to the
analogous measurement on charmed mesons, providing an insight on the
production mechanism of charmed hadrons.
In a recent letter, Physics Letters B 767 (2017) 247–252, we presented a an SU(2) NJL model with a coupling wich depends on the magnetic field in order to calculate the neutral pion mass at T = 0. In this work, we improve our model by adding the strange quark, the Polyakov loop and finite temperature. We then build a thermomagnetic dependence for the G and K couplings of the SU(3) PNJL...
Relativistic heavy-ion collisions produce a state of matter with surprising fluid properties. The study of the vorticity allows us to access a fundamental property of this matter. The STAR experiment at RHIC has observed for the first time a significant alignment between the angular momentum of the medium produced in non-central collision and the spin of $\Lambda$($\overline{\Lambda}$)...
Dielectrons produced in ultra-relativistic heavy-ion collisions at the LHC provide a unique probe of the whole system evolution as they are unperturbed by final-state interactions. The dielectron continuum is extremely rich in physics sources: on top of ordinary Dalitz and resonance decays of pseudoscalar and vector mesons, thermal black-body radiation is of particular interest as it carries...
The conventional approach to treat strangeness freezeout has been to consider a unified freezeout scheme where strangeness freezes out along with the non-strange hadrons (1CFO), with or without an additional parameter accounting for out of equilibrium
strangeness production ($\gamma_S$). Several alternate scenarios have been formulated lately- i. to consider a hadronic afterburner post...
The aim of our work is to develop a unified equation of state (EoS) for nuclear and quark matter for a wide range in temperature, density and isospin so that it becomes applicable for heavy-ion collisions as well as for the astrophysics of neutron stars, their mergers and supernova explosions. As a first step, we use improved EoS for the hadronic and quark matter phases and join them via...
Charm production in proton-proton collisions can be described by perturbative QCD calculations down to low transverse momentum ($p_\mathrm{T} \sim 0$), due to the large mass of the charm quark ($m_c >> \Lambda_{QCD}$). The measurement of charm production is thus important to constrain theoretical predictions. In p-Pb collisions, the study of charm production can help disentangle cold nuclear...
Spin alignment of vector mesons (e.g. K$^{\star}$$^{0}$) and global polarization of hyperons (e.g. $\Lambda$) in non-central high energy heavy-ion collisions could occur due to large initial angular momentum of the system. The spin alignment could also occur during the process of hadronization. The spin alignment of K$^{\star}$$^{0}$ is measured using a parameter $\rho_{00}$ characterising...
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...
We present results from the Rope Hadronization model, implemented in the DIPSY Monte Carlo event generator, specifically regarding production of strangeness in small systems. The Rope Hadronization model is built on the Lund String Hadronization model. It allows for interactions between strings in dense environments. The interacting strings form "colour ropes", characterized by their SU(3)...
Fluctuations of various observables in heavy-ion collisions at ultra-relativistic energies have been extensively studied in literature as they provide important signals regarding the formation of the Quark Gluon Plasma. In addition to being sensitive to the QCD phase transitign, the multiplicity fluctuations affect other event-by-event measurements. In this work, the centrality-dependence and...
One hundred years after Albert Einstein developed the field equations of general relativity and predicted the existence of gravitational waves (GWs), these curious spacetime-ripples have been observed from a pair of merging black holes by the LIGO detectors. As GWs emitted from merging neutron star binaries are on the verge of their first detection, it is important to understand the main...
The ultra-relativistic heavy-ion collisions at the Large Hadron Collider provide an unique opportunity to study the properties of matter at extreme energy densities where a phase transition of the hadronic matter to a deconfined medium of quarks and gluons, the Quark-Gluon Plasma (QGP) is predicted. Considerable theoretical and experimental efforts have been invested in the last 30 years to...
We investigate the fate of the light baryons in the hadronic and the quark-gluon plasma. In the confined phase a strong temperature dependence is seen in the masses of the negative-parity groundstates, while at high temperature parity doubling emerges. We study baryons with different strangeness and find a noticeable effect of the heavier s quark. This study uses nonperturbative lattice...
The production of hadrons with strange quarks within nuclear matter is fundamental to unravel the mystery about the content of neutron stars. A large fraction of strange hadrons are produced by resonances with broad masses that can undergo interference effects before they decay into strange hadrons.
We present here the first determination of the production amplitude of N*->p+Kaon+Lambda for...
We describe the propagation of heavy quarks in the quark-gluon plasma (QGP) by means of
a Boltzmann transport approach. We take into account the non-perturbative interaction between
heavy quarks and light quarks by means of a quasi particle approach in which light partons are
dressed with thermal masses. Such a model is able to catch the main features of non-perturbative
interaction as the...
The Silicon Tracking System is the central detector in the CBM experiment at FAIR. Operating in the 1 Tm dipole magnetic field, the STS will enable pile-up free detection and momentum measurement of the charged-particles originating from beam-target nuclear interactions at rates between 100 kHz and 10 MHz. It will also allow identifying particle decays occurring within the aperture, in...
ALICE is the experiment specifically designed for the study of the Quark-Gluon Plasma in heavy-ion collisions at the CERN LHC. The ALICE detector will be upgraded during the LHC Long Shutdown 2, planned for 2019-2020, in order to fully exploit the large integrated luminosity that will be provided by the LHC in Run~3 and Run~4.
The Muon Forward Tracker (MFT), an internal tracker added in the...
Measurements of quarkonium production have played an important role in understanding the properties of the Quark-Gluon Plasma (QGP) formed in relativistic heavy-ion collisions. Quarkonium suppression in the medium due to the color screening effect has been proposed as a direct signature of the QGP formation. However, other effects, such as cold nuclear matter (CNM) effects and regeneration,...
We discuss the relation between the reduction of the K* meson abundance and the kinetic freeze-out in heavy ion collisions. We evaluate the absorption cross sections of the K* meson by light mesons during the hadronic stage, and investigate effects on the K* meson abundance from both the hadronic interactions and decay of K* mesons. We show how the interplay between the interaction of the...
Extension of the ideal hadron resonance gas (HRG) model is constructed which includes attractive and repulsive van der Waals (VDW) interactions between hadrons [1]. The model employs a novel multi-component quantum statistical VDW approach which incorporates the Fermi-Dirac and Bose-Einstein effects in the system of interacting particles.
The VDW parameters a and b are fixed by the ground...
Recent ALICE collaboration measurements[1] showed a significant excess in J/$\psi$ yield at very low transverse momenta ($p_{T}<0.3$ GeV/$c$) in the peripheral Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. The same behavior of the J/$\psi$ production is observed at STAR in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. These results are interpreted as coherent photoproduction of J/$\psi$ at...
J-PARC is currently an accelerator complex utilizing high-intensity proton beam.
However, recently as a very attractive project, acceleration of heavy ions with
supplementing ion sources at J-PARC (called J-PARC-HI) is seriously contemplated by domestic as well as international communities.
The planned facility will accelerate up to $U^{92+}$ with beam energy 20 AGeV, which corresponds...
We present several results on the temperature dependence of hadronization and hadron freeze out by using different approaches. We apply the Polyakov-Nambu-Jona-Lasinio model to generate the low-lying mesons and baryons with strangeness at finite temperature. We find a flavor-dependent pattern in the temperature of the effective deconfinement, similarly to what is found in recent lattice...
The ALICE experiment has measured the production of a rich set of hadronic resonances, such as $\rho^0(770)$, K$*^0(892)$, $\phi(1020)$, $\Sigma^\pm(1385)$, $\Lambda(1520)$ and $\Xi^0(1530)$, in pp, p-Pb and Pb-Pb collisions at various energies at the LHC. A comprehensive overview and the latest results will be presented in this talk. Transverse momentum spectra, mean transverse momenta and...
The identified hadron spectra measured in high energy particle collisions are one of the most fundamental observable quantities. They accumulate information about all the processes during the collisions. They may carry information about all the microscopical and collective processes which occur during high-energy collisions, therefore it is essential to measure and analyze them as precise as...
Heavy quarks are useful probes to investigate the property of the hot and dense medium
created in high energy heavy ion collisions because they are produced via initial hard scattering
and thus are affected by the entire evolution of the medium.
The PHENIX experiment has measured open heavy flavor production via the measurement of
single lepton from the decay of inclusive heavy quarks in...
The ALICE Collaboration is preparing a major upgrade of the ALICE detector,
planned for installation in the second long LHC shutdown. The construction is
expected to be completed by 2020 for data taking until 2029. A key element of
the ALICE upgrade is the construction of a new, ultra-light, high-resolution
Inner Tracking System (ITS).
With respect to the current ITS, this upgrade is aiming...
ALICE at the Large Hadron Collider (LHC) provides unique capabilities to study charmonium production at low transverse momenta. In the early and hottest phase of nucleus-nucleus collisions the formation of a Quark-Gluon Plasma (QGP) is expected. Several QGP induced effects, such as the suppression of charmonium states due to color screening and/or an enhancement due to (re)combination of...
The ALICE experiment has measured a variety of (anti-)(hyper-) nuclei produced in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV and at 2.76 TeV. In addition, a large sample of high quality data was recorded in pp collisions at $\sqrt{s} = 7$ TeV and 13 TeV and in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5 TeV. These data are used to study the production of a variety of...
We present the first comparisons of experimental data with phenomenological results from 3+1d quasiparticle anisotropic hydrodynamics (aHydroQP). We compare charged-hadron multiplicity, identified-particle spectra, identified-particle average transverse momentum, charged-particle elliptic flow, and identified-particle elliptic flow produced in LHC 2.76 TeV Pb+Pb collisions. The dynamical...
