119194050
Production of Light Nuclei in Heavy Ion Collisions Within Multiple Freezeout Scenario
We discuss the production of light nuclei in heavy ion collisions within a multiple freezeout scenario. Thermal parameters extracted from the fits to the observed hadron yields are used to predict the multiplicities of light nuclei. Ratios of strange to non strange nuclei are found to be most sensitive to the details of the chemical freezeout. The well known disagreement between data of $^3_\Lambda\text{H/}^3\text{He}$ and $\overline{^3_\Lambda\text{H/}^3\text{He}}$ at $\sqrt{s_{NN}}=200$ GeV and models based on thermal as well as simple coalescence using a single chemical freezeout surface goes away when we let the strange and non strange hadrons freezeout at separate surfaces. At the LHC energy of $\sqrt{s_{NN}}=2700$ GeV, multiple freezeout scenario within a thermal model provides a consistent framework to describe the yields of all measured hadrons and nuclei.
59064885
Investigating the thermodynamics and susceptibilities of the (2+1) Polyakov quark meson model
We consider the (2 + 1) flavor Polyakov Quark Meson Model (PQM) and study the effect of including fermion vacuum fluctuations on the thermodynamics a nd phase diagram. The variation of the thermodynamic quantities across the phase transition region becomes smoother. This results in better agreement with the lattice QCD (LQCD) data. The critical end point is pushed into higher values of the chemical potential. We then go on to study the fluctuations of conserved charges in this model up to sixth order. Comparison is made with LQCD wherever available and overall good qualitative agreement is found, more so for the case of the normalized susceptibilities. Our study provides a solid basis for the use of PQM as an effective model to understand the topology of the QCD phase diagram.
119713356
Thermodynamics of Ideal Gas in Doubly Special Relativity
We study thermodynamics of an ideal gas in doubly special relativity. A new type of special functions (which we call ``incomplete modified Bessel functions'') emerge. We obtain a series solution for the partition function and derive thermodynamic quantities. We observe that doubly special relativity thermodynamics is nonperturbative in the special relativity and massless limits. A stiffer equation of state is found.
118252384
Sign Structure of Susceptibilities of Conserved Charges in the (2+1) Polyakov Quark Meson Model
The sign structure of correlations of conserved charges are investigated in a QCD like model: the (2+1) flavor Polyakov Quark Meson model. We compute all susceptibilities of the conserved charges on the $(\mu_{B}-T)$ plane up to fourth order and a few at higher order as well. By varying the mass of the sigma meson, we are able to study and compare scenarios with as well as without a critical point. In the hadron-quark transition regime we identify certain correlations that turn negative unlike expectation from ideal hadron resonance gas calculations. The striking feature being that these remain negative deep into the hadronic side and thus could be measured in experiments. Measurement of such quantities in heavy ion collision experiments can elucidate the location of the QCD transition curve and possibly the critical point.
118558664
Separation of flow from the chiral magnetic effect in U+U collisions using spectator asymmetry
We demonstrate that the prolate shape of the Uranium nucleus generates anti-correlation between spectator asymmetry and initial state ellipticity of the collision zone, providing a way to constrain the initial event shape in U+U collisions. As an application, we show that this can be used to separate the background contribution due to flow from the signals of chiral magnetic effect.
118651028
Fluctuations and correlations of conserved charges in the (2+1) Polyakov quark meson model
We consider the (2 + 1) flavor Polyakov quark meson model and study the fluctuations (correlations) of conserved charges up to sixth (fourth) order. A comparison is made with lattice data wherever available and overall good qualitative agreement is found, more so for the case of the normalized susceptibilities. The model predictions for the ratio of susceptibilities go to that of an ideal gas of hadrons as in hadron resonance gas model at low temperatures while at high temperature the values are close to that of an ideal gas of massless quarks. Our study provides a strong basis for the use of the Polyakov quark meson model as an effective model to understand the topology of the QCD phase diagram. DOI: 10.1103/PhysRevD.86.114021 PACS numbers: 12.39.-x, 05.40.-a, 12.38.Aw, 12.38.Mh
118399350
The black hole membrane paradigm in f (R) gravity
To an outside observer, a black hole?s event horizon appears to behave exactly like a dynamical fluid membrane. We extend this membrane paradigm to black holes in general f(R) theories of gravity. We derive the stress tensor and various transport coefficients of the fluid and find that the membrane behaves as a non-Newtonian fluid except for the special case of Einstein gravity. Using Euclidean methods, we study the thermodynamics of the membrane. We speculate on what theories of gravity admit horizons with fluid properties.