### Conveners

#### Phase diagram and search for the critical point: I

- Krishna Rajagopal (Massachusetts Inst. of Technology (US))

#### Phase diagram and search for the critical point: II

- Claudia Ratti (University of Houston)

#### Phase diagram and search for the critical point: III

- Helen Caines (Yale University (US))

Ideally, the Statistical Hadronization Model (SHM) freeze-out curve should reveal the QCD parton-hadron phase transformation line in the ($T$,$μ_B$) plane. We discuss the effects of various final state interaction phenomena, like baryon-antibaryon annihilation, core-corona effects or QCD critical point formation, which shift or deform the SHM freezeout curve. In particular, we present a method...

Clustering in systems with attractive forces are known in many physical settings:

for example in formation of globular clusters in Galaxies.

Formation of nuclear fragments is a well known phenomenon in low energy nuclear collisions,

especially at temperatures $T\sim 10\, MeV$ near the gas-liquid critical point.

At a freezeout stage of high energy collisions, with $T=100-150\, MeV$,

no...

In the coming Beam Energy Scan, RHIC will have much higher luminosity at $\sqrt{s}=20$ GeV than it will at $\sqrt{s}=10$ GeV and below. With the STAR iTPC upgrade in place they will be able to reach proton rapidities up to $|y|\sim 0.8$ where the baryon chemical potential $\mu_B$ in $\sqrt{s}=20$ GeV collisions is somewhat higher than at mid-rapidity. They may therefore be able to use the...

NA61/SHINE is a fixed target experiment operating at CERN SPS. Its main goals are to search for the critical point of the strongly interacting matter and to study the onset of deconfinement. For these goals a scan of the two dimensional phase diagram (T-$\mu_B$) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions...

The PHENIX experiment has an excellent data set for small systems including p+Au, d+Au, 3He+Au at 200 GeV as well as the d+Au beam energy scan down to 19.6 GeV. We present new measurements of $dN_{ch}/d\eta$ for all of these systems over a broad range in pseudorapidity $-3 < \eta < +3$ and event multiplicity. These measurements provide key constraints of baryon stopping models and are compared...

We examine the reliability of available methods to constrain the location

of the critical endpoint from lattice simulations. For this, we use

several lattice simulations. First, we reexamine the Fodor-Katz

critical endpoint estimate using the same staggered lattice with

modern methods. Second, we look at the compatibility of the

reweighting result with estimates of the convergence radius of...

We will present new state-of-the-art lattice QCD results on the chiral crossover temperature of QCD for moderately large baryon chemical potential. Firstly, we will present a more precise updated result for the QCD pseudo-critical temperature at zero baryon chemical potential, obtained from all possible second-order chiral susceptibilities that diverge in the chiral limit. Then we will present...

We present the first measurements of skewness and kurtosis of fluctuations of identified particle distributions measured with ALICE in Pb-Pb collisions. These distributions can be related to conserved quantum number fluctuations. The measurements can also be compared to RHIC measurements at lower energies and lattice QCD and hadronic resonance gas model calculations to obtain quantum number...

One of the main objectives of the NA61/SHINE experiment at the CERN SPS is to

study properties of strongly interacting matter (SIM). This includes a

two-dimensional scan in the beam momentum and size of the colliding system, to

investigate the onset of deconfinement discovered by NA49, and to search for

the critical point of SIM. This contribution presents first ever results on

$\phi$ meson...

Lattice QCD methods allow to calculate the thermodynamic observables at finite temperature and imaginary chemical potential. The Wuppertal-Budapest collaboration data [1,2] for the temperature dependence of the leading four Fourier coefficients of the imaginary part of the net-baryon density at imaginary baryochemical potential is analyzed. We demonstrate how the lattice behavior of these...

The ratios of the cumulants of identified net-partile multiplicity distributions have been suggested to be sensitive to the onset of QCD phase transition and to the additional fluctuations expected from the close proximity to the critical point [1,2,3].

We report the first measurements of $6^{th}$ order cumulants of net-charge distributions, up to $3^{rd}$ order cumulants of net-$\Lambda$...

The search for the QCD critical point in heavy-ion collision

experiments requires dynamical modeling of the bulk evolution of the

QCD matter as well as of the fluctuations near the critical

point. Critical slowing down means that fluctuations are significantly

deviating from equilibrium near the critical point. We generalize

hydrodynamics to quasi-equilibrium conditions where the state of...

The state-of-the-art pattern recognition method in machine learning (deep convolution neural network) is used to identify the equation of state (EoS) employed in the relativistic hydrodynamic simulations of heavy ion collisions. High-level correlations of particle spectra in transverse momentum and azimuthal angle learned by the network act as an effective EoS-meter in deciphering the nature...

For the understanding of the fluctuation measurements in heavy-ion collisions

it is crucial to develop quantitatively reliable dynamical descriptions. In order

to study the phase transition, both in crossover regime as well as near the

conjectured QCD critical point, the non-perturbative nature needs to be fully

included. In this talk, we outline a novel QCD-assisted transport approach based...

Building on an analysis of hydrodynamic long time tails for a Bjorken expansion (Akamatsu 2017, Akamatsu 2017), we discuss the hydrodynamic scales associated with transiting the critical point. First, we consider the case where the nuclear medium passes directly through the critical point. In this case, the modes with wave-number of order the inverse Kibble-Zurek length and smaller fall out of...

The measurement of open charm production was proposed as an important tool to

investigate the properties of hot and dense matter formed in nucleus-nucleus collisions as well as to provide the means for model independent interpretation of the existing data [1]. Recently, the experimental setup of the NA61/SHINE experiment was supplemented with a Vertex Detector (VD) which was motivated by the...