Modeling of Charged-Neutr**al** Kaon Fluctuat**ions** as a Signature of DCC
Product**ion** in A--A **Collisions**

**heavy**-

**ion**

**collisions**. In this work, we model the production and decay of DCCs in the context of

**heavy**-

**ion**

**collisions**at the Large Hadron Collider, and estimate the sensitivity of large acceptance detectors, such as the ALICE detector, towards the identification of such anomalous decays. Our study is based on the robust statistical observable, $\nu_{\rm dyn}$, known for its sensitivity to dynamical fluctuations. We first present simulations without DCCs, based on the HIJING and AMPT models, in order to establish an approximate reference for the magnitude of $\nu_{\rm dyn}({\rm K}^{\pm},{\rm K}^{0}_{s})$ and its centrality evolution in Pb--Pb

**collisions**at the TeV energy scale. We next introduce simple phenomenological models of K$^0_s$ vs. K$^\pm$ event-by-event yield fluctuations, which we use to study the feasibility and sensitivity of detection of the production of DCCs in

**heavy**-

**ion**

**collisions**. Although the precision of models such as HIJING and AMPT limit their use as absolute references and thus render anomalous fluctuations difficult to define precisely, our studies demonstrate that the magnitude of $\nu_{\rm dyn}({\rm K}^{\pm},{\rm K}^{0}_{s})$ is in fact very sensitive to the presence of small admixture of DCCs in normal non-DCC events. Consequently, while large values of $\nu_{\rm dyn}({\rm K}^{\pm},{\rm K}^{0}_{s})$ may not be sufficient to identify the existence of DCCs, nonetheless they constitute a first and necessary condition to signal their possible production in

**heavy**-

**ion**

**collisions**.

10/10 relevant

arXiv

Isospin splitting of p**ion** ellipt**ic** flow in relativistic **heavy**-ion
**collisions**

**heavy**-

**ion**collider by incorporating the vector-isovector potential for quarks and antiquarks with different isospins. It is found that the isospin splitting of pion elliptic flow favors a strong vector-isovector interaction, and thus serves as a probe of the quark matter equation of state as well as the QCD phase structure at finite baryon and isospin chemical potentials.

10/10 relevant

arXiv

Jet overlap in **heavy** **ion** **collisions** at LHC energies and its consequences
on jet shape

**collisions**at the LHC energies may pose a particular challenge for jet identification as multiple jets are produced per each

**collision**event. We simulate the jet evolution in central Pb-Pb events at $\sqrt{s_{\rm NN}} = 2.76$ GeV

**collision**energy with EPOS3 initial state, which typically contains multiple hard scatterings in each event. Therefore the partons from different jets have a significant chance to overlap in momentum space. We find that 30\% of the jets with $p_\perp > 50$ GeV, identified by the standard anti-$k_\perp$ jet finding algorithm with jet cone size R=0.3, contain `intruder' particles from overlapping generator-level jets. This fraction increases with increasing beam energy and increasing R. The reconstructed momentum of the jet differs from that of the modelled jet by the loss due to jet partons which are outside of the jet cone and by the gain due to intruder partons. The sum of both may be positive or negative. These intruder partons particularly affect the radial jet momentum distribution because they contribute mostly at large angles $\Delta r$ with respect to the jet centre. The study stresses the importance of the jet overlap effect emerging in central lead-lead

**collisions**at the LHC energies while being negligible in peripheral PbPb or $p$Pb/$pp$

**collisions**.

10/10 relevant

arXiv

Calculating n-Point Charge Correlat**ions** in Evolving Systems

**heavy**-

**ion**collisions, and can account for correlations indexed by up, down and strange charges. Understanding the evolution of such correlations is crucial if one is to interpret measurements of charge fluctuations from the Relativistic

**Heavy**-

**Ion**Collider.

9/10 relevant

arXiv

Centrality Dependence of Multiplicity Fluctuat**ions** in Ion-**Ion** **Collisions**
from the Beam Energy Scan at FAIR

**ions**and event-by-event multiplicity fluctuations in AuAu

**collisions**at energies in future

**heavy**-ion experiment at the Facility for Anti-proton and

**Ion**Research (FAIR) are investigated. Expand abstract.

**collisions**at energies in future

**heavy**-

**ion**experiment at the Facility for Anti-proton and

**Ion**Research (FAIR) are investigated. Events corresponding to FAIR energies are simulated in the frame work of Ultra Relativistic Quantum Molecular Dynamics (URQMD) model. It is observed that the mean and the width of multiplicity distributions monotonically increase with beam energy. The trend of variations of dispersion with mean number of participating nucleons for the centrality-bin width of 5\% are in accord with the Central Limit Theorem. The multiplicity distributions in various centrality bins as well as for full event samples are observed to obey Koba, Nielsen and Olesen (KNO) scaling. The trends of variations of scaled variance with beam energy are also found to support the KNO scaling predictions for larger

**collision**centrality. The findings also reveal that the statistical fluctuations in 5\% centrality-bin width appear to be under control.

8/10 relevant

arXiv

Coupling Constant Correct**ions** in a Holograph**ic** Model of **Heavy** **Ion**
**Collisions** with Nonzero Baryon Number Density

**al**gravitational descript

**ion**of such

**collisions**in the most general bulk theory with a four-derivative gravitational action containing a dynam

**ical**metr

**ic**and a gauge field in five dimensions. Expand abstract.

**collisions**of

**heavy**

**ions**result in the formation of a droplet of a strongly coupled liquid state of QCD matter known as quark-gluon plasma. By using gauge-gravity duality (holography), a model of a rapidly hydrodynamizing and thermalizing process like this can be constructed by colliding sheets of energy density moving at the speed of light and tracking the subsequent evolution. In this work, we consider the dual gravitational description of such

**collisions**in the most general bulk theory with a four-derivative gravitational action containing a dynamical metric and a gauge field in five dimensions. Introducing the bulk gauge field enables the analysis of

**collisions**of sheets which carry nonzero "baryon" number density in addition to energy density. Introducing the four-derivative terms enables consideration of such

**collisions**in a gauge theory with finite gauge coupling, working perturbatively in the inverse coupling. While the dynamics of energy and momentum in the presence of perturbative inverse-coupling corrections has been analyzed previously, here we are able to determine the effect of such finite coupling corrections on the dynamics of the density of a conserved global charge, which we take as a model for the dynamics of nonzero baryon number density. In accordance with expectations, as the coupling is reduced we observe that after the

**collisions**less baryon density ends up stopped at mid-rapidity and more of it ends up moving near the lightcone.

10/10 relevant

arXiv

Product**ion** of multi-charm**ed** hadrons by recombin**ation** in **heavy** ion
**collisions**

**heavy**

**ion**

**collisions**by focusing on the production of $\Xi_{cc}$, $\Xi_{cc}^*$, $\Omega_{scc}$, $\Omega_{scc}^*$, $\Omega_{ccc}$ baryons and X(3872) mesons. Starting from the estimation of yields for those hadrons at chemical freeze-out in both the statistical and coalescence model, we evaluate their transverse momentum distributions at mid-rapidity in the coalescence model. We show that yields of multi-charmed hadrons in

**heavy**

**ion**

**collisions**at RHIC and LHC are large enough, and thereby not only multi-charmed hadrons observed so far, e.g., the $\Xi_{cc}$ but also those which have not been observed yet, can be discovered sufficiently in

**heavy**

**ion**

**collisions**. We also find that the transverse momentum distribution ratio between various multi-charmed hadrons sensitively reflects the interplay between quark contents of corresponding hadrons as well as the transverse momentum distribution of charm quarks at the hadronization point, and therefore we insist that studying both the transverse momentum distributions of multi-charmed hadrons themselves and transverse momentum distribution ratios between various multi-charmed hadrons provide us with useful information on hadron production mechanism involving charm quarks in

**heavy**

**ion**

**collisions**.

10/10 relevant

arXiv

Dipole evolution: perspectives for collectivity and $\gamma^*$A
**collisions**

**collisions**of protons, as well as

**collisions**of

**heavy**

**ions**. In this paper eccentricities and eccentricity fluctuations are predicted using the dipole formulation of BFKL evolution. Furthermore, first steps are taken towards generation of fully exclusive final states of $\gamma^*$A collisions, by assessing the importance of colour fluctuations in the initial state. Such steps are crucial for the preparation of event generators for a future electron-

**ion**collider. Due to the connection between an impact parameter picture of the proton structure, and cross sections of ep and pp collisions, the model parameters can be fully determined by fits to such quantities, leaving results as real predictions of the model.

5/10 relevant

arXiv

Pseudo-rapidity dependent hydrodynam**ic** response in **heavy**-**ion** **collisions**

**heavy**-

**ion**collisions, in response to a fluctuating three-dimensional initial density profile. By analyzing the medium expansion using event-by-event simulations of 3+1D MUSIC, with initial conditions generated via the AMPT model, the differential response relation is verified. Given the response relation, we are able to separate the two-point correlation of elliptic flow in pseudo-rapidity into fluid response and two-point correlation of initial eccentricity. The fluid response contains information of the speed of sound and shear viscosity of the medium. From the pseudo-rapidity dependent response relation, a finite radius of convergence of hydrodynamic gradient expansion is obtained with respect to realistic fluids in

**heavy**-

**ion**

**collisions**.

10/10 relevant

arXiv

Primord**ial** fluctuat**ions** in **heavy**-**ion** **collisions**

**collisions**between localized charges and a smooth nucleus. Each of these interactions creates a sharply-peaked source of energy density falling off at large distances like $1/r^2$, corresponding to the two-dimensional Coulomb field of a point charge. Our model reproduces the one-point and two-point functions of the energy density field calculated in the framework of the color glass condensate effective theory, to leading logarithmic accuracy. We apply it to the description of eccentricity fluctuations. Unlike other existing models of initial conditions for

**heavy**-

**ion**collisions, it allows us to reproduce simultaneously the centrality dependence of elliptic and triangular flow.

10/10 relevant

arXiv