Dileptons and photons are unique tools to study the space–time evolution of the hot and dense matter created in ultra-relativistic heavy-ion collisions. They are produced continuously by a variety of processes, in particular prompt and thermal photons and semi-leptonic heavy-flavour hadron decays, during the entire history of the collision and traverse the medium...
Exploring the QCD phase diagram and searching for the QCD critical point are some of the main goals of heavy-ion collision experiments. The yields of identified hadrons and (multi-) strange hadrons provide information about the phase diagram and particle production in these collisions. In 2017 the STAR experiment collected large dataset of Au+Au collisions at 54.4 GeV.
The production of...
In recent years, a significant theoretical effort has been made towards a dynamical description of quarkonia inside the Quark-Gluon Plasma (QGP), using the open quantum systems formalism. In this framework, one can get a real-time description of a quantum system (here the quarkonium) in interaction with a thermal bath (the QGP) by integrating out the bath degrees of freedom and studying the...
We present the elliptic azimuthal anisotropy coefficient ($v_2$) of the identified strange hadrons $K_{S}^{0}$ and $\Lambda$ using the scalar product and multi-particle cumulant methods in pPb collisions at 8.16 TeV and PbPb collisions at 5.02 TeV at mid-rapidity (|y|<1). The data samples were collected by the CMS experiment at the LHC. The scalar product and multi-particle $v_2$ values are...
We describe the propagation of heavy quarks (HQs), charm and bottom, in the quark-gluon plasma by means of a full Boltzmann transport approach within a coalescence plus fragmentation hadronization and including event-by-event fluctuations. The non-perturbative dynamics and the interaction between HQs and light quarks have been taken into account through a Quasi-Particle Model (QPM). We show...
Heavy quarks (HQs) are mostly created in the very initial stages of the relativistic heavy-ion collisions and are identified as effective probes to study the properties of the quark-gluon plasma (QGP). It is believed that an intense magnetic field has been created in the early stages of non-central collisions. The interactions of the heavy quarks with the magnetized medium particles are...
Recently, significant enhancements of $e^{+}e^{−}$ pairs at very low transverse momentum ($p_{\rm{T}}$) were observed by the STAR collaboration in peripheral Au+Au collisions. The excess can be explained by photon-photon interactions induced by the extremely strong electromagnetic field produced by the fast moving heavy ions. While such photon-photon interactions were traditionally studied in...
The study of identified particle production as a function of event multiplicity is a key tool for understanding the similarities and differences among different colliding systems. The multiplicity dependence of particle production has been previously studied as a function of center-of-mass energy in pp and Pb-Pb collisions. Now for the first time, we can investigate how particle production is...
One of the main goals of the STAR experiment is to study the properties of QCD matter at various temperatures and/or baryon densities. With this motivation, the STAR experiment has collected data in the nuclear collisions at centre-of-mass energies ($\sqrt{s_{\rm{NN}}}$) = 3.0-200 GeV. The azimuthal anisotropy of multi-strange hadrons plays an important role in characterizing the properties...
The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) hadron is studied in PbPb collisions at a center-of-mass energy of 5.02 TeV per nucleon pair, using the decay chain $X(3872)\rightarrow J/\psi\pi\pi\rightarrow \mu^{+}\mu^{-}\pi^{+}\pi^{-}$ decay chain. The data were recorded with the CMS detector in 2018 and correspond to an integrated...
The production of multi-strange hadrons in proton-proton interactions is recently studied with the NA61/SHINE experiment at the SPS. These particles are reconstructed via their weak decay topologies, exploiting the tracking and particle identification capabilities of NA61/SHINE. New measurements of rapidity and transverse momentum spectra of $\Xi^{-}$, $\Omega^{-}$ baryons, and $\Xi$...
Exploring the nature of exotic multiquark candidates such as the X(3872) plays a pivotal role in understanding quantum chromodynamics (QCD). Despite significant efforts, consensus on their internal structures is still lacking. As a prime example, it remains a pressing open question to decipher the X(3872) state between two popular exotic configurations: a loose hadronic molecule or a compact...
Measurements of open heavy-flavor hadron and heavy-flavor jet production in heavy-ion collisions provide a powerful tool to study both initial-state effects on heavy-quark production and final-state interactions between heavy quarks and the Quark-Gluon Plasma (QGP).
These measurements are performed with the ATLAS detector at the LHC and capitalize on the large statistics of the Run 2 Pb+Pb...
We study the in-medium effects in strangeness production
in heavy-ion collisions at (sub-)-threshold energies of 1 - 2 A GeV based on
the microscopic Parton-Hadron-String Dynamics (PHSD) transport approach.
The in-medium modifications of the antikaon $(\bar K = K^-, \bar K^0)$ properties
are described via the self-consistent coupled-channel unitarized scheme
based on a SU(3) chiral...
The main goal of the ALICE experiment is to study the physics of strongly interacting matter, including the properties of the quark-gluon plasma (QGP).The relative production of strange hadrons with respect to non-strange hadrons in heavy-ion collisions was historically considered as one of the signatures of QGP formation. However, recent measurements in proton-proton (pp) ...
Based on the fact that the mass difference between the chiral partners is an
order parameter of chiral phase transition and that the chiral order parameter
reduces substantially at the chemical freeze-out point in ultra-relativistic
heavy ion collisions, we argue that the production ratio of $K_1$ over $K^*$ in
such collisions should be substantially larger than that predicted in...
We present for the first time results on final hadron production, with and without strangeness content, in Ultrarelativistic Heavy Ion Collisions at RHIC and LHC center of mass energies obtained combining a full 3+1D relativistic Boltzmann transport approach with a statistical hadronization mechanism. The non-perturbative interaction between quarks and gluons is described by means of a...
In relativistic nuclear collisions the production of hadrons with light (u,d,s) quarks is quantitatively described in the framework of the Statistical Hadronization Model (SHM). Since charm quarks are dominantly produced in initial hard collisions but interact strongly in the hot fireball, charmed hadrons can be incorporated into the SHM by treating charm quarks as 'impurities' with thermal...
A fundamental ingredient of the ALICE physics programme for the new decade is a comprehensive study of charm and multi-charm baryon production. Because charm is exclusively produced in initial hard scatterings, such measurements may provide unique insight into the QGP medium as well as hadronization from proton-proton to lead-lead collisions.
We will present a new method for detection of...
The systematic study of hadronic elliptic flow in various relativistic heavy ion collisions is important for the investigation of the initial geometry influence on the quark gluon plasma characteristics. The 𝝋-meson consists of strange and antistrange quarks and has a small interaction cross section with non-strange hadrons. Therefore, 𝝋-mesons are barely affected by late hadronic stage and...
We present Azimuthal Anisotropy Scaling Functions for identified particle species spanning beam energies from RHIC to the LHC. The scaling functions, which clarify the respective influence of initial-state eccentricity, expansion dynamics, and the transport coefficients, indicate characteristic signatures for the transport coefficient's dependencies on the temperature ($T$) and the baryon...
We generalize the Cooper-Frye particlization routine to make it suitable for describing event-by-event fluctuations in heavy-ion collisions. This is achieved via a newly developed subensemble method, allowing to incorporate the effects of exact global conservation of multiple charges, thermal smearing, and resonance decays on fluctuations of various particle numbers. Utilizing viscous...
LHCb has the unique capability to operate in fixed-target mode to study collisions of the LHC beams on fixed targets. In Run3, the internal gas target is going to be upgraded to allow for a wider selection of target gas species and a significant increase of the rates of fixed target collisions by up to two orders of magnitude. Along with significant data acquisition and tracking upgrades, the...
In the study of QCD phase structure and search of the QCD phase boundary and critical point, higher-order cumulants of conserved quantities are proposed as promising observables and have been studied extensively both experimentally and theoretically. For $4^{th}$-order cumulants it is predicted that there will be a non-monotonic energy dependence trend. For $5^{th}$- and $6^{th}$-order...
Quarkonium production in small systems has been the subject of many theoretical and experimental studies. In proton-nucleus (p-A) collisions, their production is sensitive to cold nuclear matter effects such as nuclear modification of parton densities, parton energy loss via initial-state radiation and transverse momentum broadening due to multiple soft collisions. Furthermore,...
We investigate the chemical freeze-out in heavy-ion collisions (HICs) and the impact of the hadronic spectrum on thermal model analyses [1, 2]. Detailed knowledge of the hadronic spectrum is still an open question, which has phenomenological consequences on the study of HICs. By varying the number of resonances included in Hadron Resonance Gas (HRG) Model calculations, we can shed light on...
Current experiments at the Relativistic Heavy Ion Collider (RHIC) are probing
finite baryon densities where the shear viscosity to enthalpy ratio $\eta T/w$
of the Quark Gluon Plasma remains unknown. We use the Hadron Resonance Gas
(HRG) model with the most up-to-date hadron list to calculate $\eta T/w$ at low
temperatures and at finite baryon densities $\rho_B$. We then match $\eta...
Cumulants of net charge fluctuations and their correlations at vanishing
values of the conserved charge chemical potentials ($\mu_{B,Q,S}=0$)
provide the basis for Taylor expansions of various thermodynamic observables
at non-zero values of the chemical potentials. At $\mu_{B,Q,S}=0$ continuum
extrapolated results for these cumulants can directly be compared
with charge fluctuations...
A new heavy-ion experiment on fixed target, NA60+, has been proposed at the CERN SPS for data taking in the next years. Its main goals will be focused on precision studies of thermal dimuons, heavy quark and strangeness production in Pb-Pb collisions at center-of-mass energies ranging from 5 to 17 GeV. The experiment will profit from the high-intensity beams provided by the CERN SPS, that will...
Fluctuation observables in heavy-ion collisions probe the constituents, the chemical freeze-out and the transport properties of strongly interacting matter, and signal phase transitions. We present results for second order fluctuations of the conserved charges in QCD from a stochastic diffusion model in a Bjorken-type expansion background. The impact of the cross couplings between the three...
The large values and the constituent-quark-number (NCQ) scaling of the elliptic flow of low-$p_T$ $D$ mesons imply that charm quarks, initially produced through hard processes, might be partially thermalized through the strong interactions with the quark-gluon plasma (QGP) in high-energy heavy-ion collisions.
To quantify the degree of thermalization of low-$p_T$ charm quarks, we compare...
Particle production and anisotropic flow measurements have been used to investigate the properties of the QCD matter produced in heavy ion collisions.The RHIC Beam Energy Scan program covers a wide range of energies, including the transition from a partonic dominated area to hadronic dominated area. Of particular interest is the high baryon density region which is accessible through production...
The Compressed Baryonic Matter (CBM) experiment at FAIR will investigate the QCD phase diagram in the region of high net-baryon densities (µB > 500 MeV) in the collision energy range of √sNN = 2.7−4.9 GeV with high interaction rate, up to 10 MHz, provided by the SIS100 accelerator. Enhanced production of strange baryons can signal transition to a new phase of the QCD matter. Λ hyperons are the...
The Beam Energy Scan program at RHIC (Relativistic Heavy Ion Collider)
is searching for the QCD critical point or a first order phase transition. The main signal for the
critical point is the kurtosis of the distribution of proton yields obtained on an event by
event basis where one expects a peak at the critical point. However, its exact behavior is
still an open question due to...
The precise knowledge of the strong interaction between kaons and nucleons is a key element needed for the chiral effective theories that describe the interaction between hadrons in the non–pertubative regime of QCD. Additionally, the knowledge of the interaction plays an important role in the study of the equation of state of dense baryonic matter, and hence has important implications for the...
In this contribution, we present the latest measurements of $\Lambda_\mathrm{c}^+$, $\Xi_\mathrm{c}^{0,+}$, $\Sigma_\mathrm{c}^{0,++}$, and the first measurement of $\Omega_\mathrm{c}^0$ baryons performed with the ALICE detector at midrapidity in pp collisions at $\sqrt{s}=5.02$ and 13 TeV. Recent measurements of charm-baryon production at midrapidity by the ALICE Collaboration in small...
Significant strangeness enhancement and radial flow have been observed in high-multiplicity pp collisions at LHC. The origin of these effects is still under debate. In this contribution, new and more differential measurements are presented, making use of event-shape techniques to study final-state topologies: (i) the transverse spherocity, which aims to classify events into jetty...
The chemical freeze-out is often related to the phase transition to a deconfined state of matter, the Quark Gluon Plasma. We introduce a novel approach based on elastic and inelastic scattering rates to extract the hyper-surface of the chemical freeze-out from a hadronic transport simulation. We use the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model to extract the chemical...
Hadronic resonances, thanks to their relatively short lifetimes, can be used to probe the properties of the hadronic phase in ultrarelativistic heavy-ion collisions. In particular they are exploited to investigate the interplay between particle re-scattering and regeneration after hadronization. Resonances can also be used to explore the various mechanisms that influence the shape of particle...
Ultrarelativistic heavy-ion collision are characterized by the presence of very intense electromagnetic fields, which attain their maximal strength in the early stage and interplay with the strong vorticity induced in the plasma by the large angular momentum of the colliding nuclei. As a promising observable influenced by these phenomena we study the directed flow $v_1$ of neutral $D$ mesons...
Measurements of heavy-flavor hadron production and elliptic flow ($v_{2}$) are unique and indispensable probes to the properties of the Quark-Gluon Plasma (QGP). Measurements of the production of electrons from open charm and bottom hadron decays in Au+Au collisions serve as a valuable tool to investigate the mass hierarchy of the parton energy loss. Meanwhile, measuring $v_{2}$ of heavy...
Searching for exotic state particles and studying their properties have furthered our understanding of quantum chromodynamics (QCD). The $f_{0}(980)$ resonance is an exotic state with relatively higher production rate in relativistic heavy-ion collisions, decaying primarily into $\pi\pi$. Currently the structure and quark content of the $f_{0}(980)$ are unknown with several predictions from...
We propose an improved quark coalescence model with spin degrees of freedom for vector mesons by spin density matrix in phase space. This model allows us to estimate spin alignments of vector mesons using polarizations of quarks. We propose that a significant positive deviation from 1/3 of the spin density matrix element $\rho_{00}$ for the $\phi$ meson may attribute to the electric part of...
In heavy-ion collisions, the spin polarization of $\Lambda$ hyperon is an important measure to probe the vorticity of the quark-gluon plasma. On the other hand, other hyperons such as $\Xi^{-}$ and $\Omega^{-}$ should also possess the global polarization similar to $\Lambda$.
In this talk, I will show our recent theoretical results on the global polarization of $\Lambda$, $\Xi^{-}$ and...
In order to constrain the equation of state of dense objects like neutron stars (NS) and subsequently solve the puzzle about their content, it is fundamental to understand the interaction between their hypothetical constituents. Hyperons might be contained in the core of NS. When becoming sufficiently abundant, in addition to the hyperon-nucleon interaction also the self-interaction of...
We compute resonance (rho, K*(892), phi(1020), f2'(1252), Lambda(1520), Sigma(1775)) yields and spectra in PbPb collisions at 5.02 TeV using hydrodynamics with hadronic afterburner. The yields and <pT> agree with available experimental data. With the afterburner the yields are substantially suppressed and the mean transverse momenta are substantially enhanced compared to the case without...
Mesons carrying heavy flavor (charm and beauty) are valuable probes of the quark-gluon plasma (QGP) created in heavy-ion collisions. Therefore a proper theoretical understanding of their modification in a thermal medium is required for a better description of the experimental data collected at RHIC and LHC. The modification of open heavy-flavor mesons in a hot medium of light mesons can be...
The hot and dense medium produced in relativistic heavy-ion collisions has been conjectured to be accompanied by an axial charge asymmetry that may lead to a separation of electric charges in the direction of the extremely strong ($10^{18}$ Gauss) magnetic field ($B$),also known as the Chiral Magnetic Effect (CME). The measurement of azimuthal correlator ($\Delta\gamma$) with respect to the...
Understanding of baryon-baryon interactions is important to examine the existence of stranglets and various exotic hadrons, e.g. H-dibaryon, and to model of astronomical objects such as neutron stars. However hyperon-nucleon and hyperon-hyperon interactions are not fully understood yet. In high energy heavy-ion collisions, a large number of particles including (multi-)strangeness are produced,...
We will discuss thermal modifications of charmonium and bottomonium spectral properties in a hot gluonic medium from continuum extrapolated lattice results. The dissociation temperatures of quarkonia as well as charm and bottom quark diffusion coefficients are presented in the temperature region from $1.1T_c$ to $2.25T_c$ in the quenched approximation with valence quarks tuned to physical...
I shall present an analysis of the thermal composition of the S=-1 strange baryons using an S-matrix formulation of statistical mechanics. The thermal abundances are computed based on the density of states extracted from a coupled-channel model. The approach entails a consistent treatment of resonances and naturally incorporates nonresonant interactions and the contribution from some...
Studies on the production of heavy-flavour in pp and p-Pb collisions are of primary importance as a baseline to characterise the QGP medium created in ultrarelativistic heavy-ion collisions, and as tests of perturbative QCD and cold-matter effects in the nuclear medium. Recent measurements performed in small collision systems have revealed unexpected features, as the enhancement of...
We present an updated event generator THESEUS, based on the three-fluid dynamics (3FD), complemented by UrQMD cascade for the late stage of the nuclear collision. The generator is extended to simulate light-nuclei production in relativistic heavy-ion collisions via thermal mechanism, on the same basis as hadrons.
We present the rapidity, transverse momentum spectra, first ($v_1$) and second...
We analyze the spin polarization generated from the hydrodynamic gradients. In addition to the widely studied effects of thermal vorticity, we identify an undiscovered contribution, namely, shear-induced polarization (SIP). That is, shear strength $\sigma^{\mu\nu}$, the traceless and symmetric part of the flow gradient, will give rise to spin polarization in momentum space. SIP can be viewed...
We study the role of dynamical strange quarks in transport properties of the QGP utilizing the quasiparticle approach based on the kinetic theory. The interactions with a hot medium are encoded in the quasiparticle excitations, with the temperature dependence of the dynamical masses specified by the effective coupling extracted from the lattice QCD thermodynamics.
Evaluation of the...
We outline a theoretical approach supporting strong phase transitions from normal nuclear matter to the deconfined quark-gluon plasma, in the equation of state (EOS) for compact star matter, from vanishing to moderately high temperatures that are accessible for BM(a)N and MPD experiments at NICA. We study the connection of such hybrid EOS with the mass-radius relation of cold compact stars,...
Taylor expansion of the equation of state of QCD
suffers from shortcomings at chemical potentials $\mu_B \geq (2-2.5)T$.
First, one faces difficulties inherent in performing such an expansion
with a limited number of coefficients; second,
higher order coefficients determined from
lattice calculations suffer from a poor signal-to-noise ratio.
We present a novel scheme for extrapolating...
In this contribution, measurements of open charm and beauty production via heavy-flavour hadron decay leptons, prompt and non prompt $\mathrm{D}^+$ and $\mathrm{D}^0$ in pp collisions are presented. In heavy-ion collisions, measurements of the production of leptons from heavy-flavour hadron decays and the modification of their spectra in different collision systems, like Xe--Xe and Pb--Pb, are...
The system created in relativistic nucleus-nucleus collisions may possess large orbital angular momentum leading to the global polarization of particles perpendicular to the reaction plane. The local asymmetries in the velocity fields due to anisotropic flow can also generate vorticity and particle polarization along the beam direction. In parity-violating weak decays of hyperons, the momentum...
The determination of freeze-out parameters from experimental data on particle yields and higher order cumulants crucially relies on thermodynamic relations known to be valid in hadron resonance gas models. In particular, the determination of chemical potentials at the time of freeze-out, obtained from ratios of first and second order cumulants, relies on the assumption that particle...
In the quark-gluon plasma produced in high-energy heavy-ion collisions, mesons with heavy quarks can dissociate and recombine. The CMS measurements of the nuclear modification factor of prompt and non-prompt J/ψ mesons and of Upsilon mesons help understanding these processes. Furthermore, compared to their low yield in proton-proton collisions, Bc meson production could be dramatically...
The physics interpretation of the recent measurements of the spin polarization of Λ hyperons produced in relativistic heavy-ion collisions is discussed. We suggest that the polarization measured in the Λ rest frame should be projected along the direction of the total angular momentum that is first transformed to the same frame, and only then averaged over Λ's with different momenta in the...
The measurement of low-energy cosmic antinuclei may reveal the existence of exotic processes such as dark-matter annihilation, since the production rate of these ions through ordinary secondary processes is very low. However, the lack of experimental data at low energies, where both the antinuclei production and inelastic cross sections are very poorly known, prevents precise predictions of...
Using non-relativistic QCD techniques on finite temperature lattice configurations, we will present results pertaining to the fate of the Bottom and anti-Bottom quarkonium states of Υ(1S), Υ(2S) and Υ(3S) in Quark-Gluon-Plasma (QGP). We will present results on how the mass and spectral width of these states change with temperature. We will also show new results on how the finite temperature...
Non-central heavy-ion collisions produce a large angular momentum that leads to vorticity of the created system. Due to the spin-orbit coupling, spin directions
of particles are aligned with the orbital angular momentum of the system. Global
polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons has been measured in Au+Au collisions from $\sqrt{s_{\rm{NN}}}$ = 7.7 GeV to 200 GeV[1][2]. The...
Measurements of $\mathrm{D}_s^+$ mesons originating from the hadronisation of a charm quark (prompt) and from beauty-hadron decays (non-prompt) offer a unique tool to study the hadronisation of both charm a-proton and heavy-ion collisions.
In this contribution, the latest results of the ALICE Collaboration on the production of prompt and non-prompt $\mathrm{D}_s^+$ in pp collisions at...
We present the latest predictions from AdS/CFT for $D$ and $B$ meson suppression $R_{AA}(p_T,\eta)$ and $v_2(p_T,\eta)$ in Pb+Pb collisions of various centrality classes at multiple LHC center-of-mass energies. Included in these predictions are systematic theoretical uncertainties due to the currently incomplete understanding of strongly-coupled energy loss and from mapping QCD onto N=4 SYM. ...
In a non-central nucleus-nucleus collision, the colliding system carries large orbital angular momentum, part of which remains within the hot dense matter created by the collision. This angular momentum turns into complex fluid vorticity structures in the rapidly expanding bulk fluid and eventually manifests itself through the global spin polarization of produced particles such as hyperons....
Second order susceptibilities $\chi^{11}_{ij}$ of baryon, electric, and strangeness, $B$, $Q$, and $S$, charges, are calculated in the Chiral Mean Field (CMF) model and compared to available lattice QCD data. The susceptibilities are sensitive to the short range repulsive interactions between different hadron species, especially to the hardcore repulsion of hyperons. Decreasing the hyperons...
In the primordial QGP filling the early Universe the abundant strangeness is in chemical equilibrium since the characteristic Hubble time constant $H^{-1}\simeq 1\mu s$. Upon hadronization near to $T=150$ MeV one may think that relatively short lived massive strange hadrons decay rapidly and strangeness disappears. However, using detailed balance considerations for inverse decay reactions...
In non-central heavy-ion collisions the orbital angular momentum can reach high values up $10^4\hbar$. This might lead to a global spin polarization of the particles being produced. The STAR results, as measured during the beam energy scan phase I, show an enhancement of the global polarization towards lower beam energies. At a collision energy of $\sqrt{s_{NN}} = 7.7\,$GeV a polarization of a...
Recent observation data of pulsar masses led us to estimate nuclear parameters, however, these predictions are strongly uncertain due to the masquarade problem. To resolve this we introduced, te maximmal-mass compact star scenario, and took into account data satisfying this criteria. We tested our method, applying the extended σ-ω model in the mean-field approximation at zero temperature and...
Heavy quark transport coefficients calculated from first-principles QCD are a crucial input for transport models. Utilizing the heavy quark limit, we will discuss the results of a novel approach to nonperturbatively estimate the heavy quark momentum diffusion coefficient in a hot gluonic medium from gradient-flowed color-electric correlators on the lattice. Unlike others, this approach can be...
Bottomonia have played a key role to understand the dynamics in high-energy heavy-ion collisions. In PbPb collisions, the modification of bottomonium production provides a crucial input for thermal property of the hot QCD medium. On there other hand, in smaller collision systems, it also contains intensive interest subjects such as Cold Nuclear Matter (CNM) effects. In this talk, we report the...
In this talk I will briefly review recent progress on two problems in few-body
hypernuclei:
(i) The Lambda-3H (hypertriton) lifetime puzzle [1,2,3].
(ii) The onset of binding in Lambda-Lambda hypernuclei [4,5].
References:
[1] A. Gal, H. Garcilazo,
Towards resolving the hypertriton lifetime puzzle,
Phys. Lett. B 791 (2019) 48.
[2] Lifetime of the hypertriton,
F....
We study charmonia in electromagnetic and rotational fields in the frame of a potential model. Different from the temperature field which is isotropic and leads to the well-known charmonium dissociation, the electromagnetic and rotational fields break down the radial symmetry, and the competition between strong interaction and electromagnetic and rotational interaction in the direction of...
Previously reported ALICE measurements have shown that the inclusive production rate of (multi-)strange particles varies smoothly as a function of the size of the collision system, as measured by charged-particle multiplicity in pp, p-Pb, and Pb-Pb collisions. However, more detailed investigation reveals an overall enhancement in the yield of strange baryons relative to mesons for systems...
The Λ binding energy difference, which is called the charge symmetry breaking in the ground states of a pair of A = 4 hypernuclei, $^{4}_{\Lambda}$H and $^{4}_{\Lambda}$He, was measured to be $\Delta B^{4}_{\Lambda}(0^{+}_{g.s.})$ ≈ 350 keV in nuclear emulsion experiments in 1970s. In the 2015 experiment from J-PARC, the binding energy difference in excited states $\Delta...
We suggest to explore an entirely new method to experimentally and theoretically study the phase diagram of strongly interacting matter based on the triple nuclear collisions (TNC). The key element of such experiments is to use the superthin solid target operated in the core of two colliding beams [1]. Our approach is based on the successful data-taking in the LHCb experiment in which the...
The energy densities reached in high-energy hadronic collisions at the LHC allow significant production of light (anti)nuclei. Their production yields have been measured as a function of $p_{\rm T}$ and charged-particle multiplicity in different collision systems and at different center-of-mass energies by ALICE. One of the most interesting results obtained from such a large variety of...
The production of quarkonia is one of the first proposed probes of the QGP properties in heavy-ion collisions. Since heavy quarks are produced during the early hard partonic collisions, they experience the entire evolution of the fireball. The suppression of quarkonium bound states by the free color charges of the dense deconfined medium, as well as the charmonium regeneration by...
The $^{3}_{\Lambda}\text{H}$ is a bound state of proton (p), neutron (n) and $\Lambda$. Studying its characteristics provides insights about the strong interaction between the $\Lambda$ and ordinary nucleons. In particular, the $^{3}_{\Lambda}\text{H}$ is an extremely loosely bound object, with a large wave function. As a consequence, the measured (anti-)$^{3}_{\Lambda}\text{H}$ production...
One of the remaining puzzles in heavy-ion physics is that enhanced yields of multistrange hadrons — believed to be a signature of the quark–gluon plasma — are not only observed in heavy-ion collisions, but also in high-multiplicity proton-proton and proton-nucleus collisions. Various phenomenological models have been developed to try to understand this, such as rope hadronisation (available in...
We study the cluster and hypernuclei production in heavy-ion collisions from SIS to RHIC energies based on the n-body dynamical transport approach PHQMD (Parton-Hadron-Quantum-Molecular-Dynamics). In PHQMD clusters are formed dynamically due to the interactions between baryons described on a basis of Quantum Molecular Dynamics (QMD) which allows to propagate the n-body Wigner density and...
The heavy-quark effects on the equation of state for cold and dense quark matter are obtained from perturbative QCD, yielding observables parametrized only by the renormalization scale. In particular, we investigate the thermodynamics of charm quark matter under the constraints of β equilibrium and electric charge neutrality in a region of densities where perturbative QCD is, in principle,...
Heavy quarkonia are ideal probes of the Quark-Gluon Plasma (QGP). The J/ψ suppression due to the color screening effect in heavy-ion collisions is a key experimental observable to study the QGP. At RHIC energies, charm quark recombination could also affect the J/ψ yield in the QGP. Measurements of J/ψ production in Au+Au collisions at different collision energies will help to understand the...
We show that high-$p_{\perp}$ $R_{AA}$ and $v_2$ are way more sensitive to the QGP thermalization time, $\tau_0$, than the distributions of low-$p_{\perp}$ particles, and that the high-$p_{\perp}$ observables prefer relatively late thermalization at $\tau_0$ ∼ 1 fm/c. To calculate high-$p_{\perp}$ $R_{AA}$ and $v_2$, we employ our newly developed DREENA-A formalism, which combines...
The study of hyperon-nucleon (Y-N) interactions is of great interest in recent years because of its relation to high-density matter systems. For example, the presence of hyperons inside neutron stars would soften the equation of state. Hypernuclei, bound states of nucleons and hyperons, serve as a probe to study the Y-N interaction.
In this talk, the lifetime of ${}^{3}_{\Lambda}$H and...
Measurements of open heavy-flavor hadron production in proton-proton collisions provide a crucial baseline for interpreting measurements in nucleus-nucleus collisions, and allow for the investigation of the origin and underlying mechanism of collective effects in small systems.
These measurements are performed with the ATLAS detector at the LHC and capitalize on the large Run 2 $pp$ dataset...
Quarkonia are among the most important tools for studying Quantum Chromodynamics (QCD) in high energy hadronic collisions. Despite decades of extensive studies, we still have a limited knowledge of their production mechanism and hadronization; and carrying out as many measurements as possible in $p$$+$$p$ collisions over a broad kinematic region at different energies is essential to...
DREENA framework is based on our dynamical energy loss formalism, which takes into account finite size, finite temperature QCD medium consisting of dynamical (moving) partons. Both radiative and collisional energy losses are calculated under the same theoretical framework in the dynamical energy loss formalism, which is applicable to both light and heavy flavor observables. We generalized the...
