119240025
The Freezeout Hypersurface at LHC from particle spectra: Flavor and Centrality Dependence
Abstract We extract the freezeout hypersurface in Pb-Pb collisions at √ sNN = 2700 GeV at the CERN Large Hadron Collider by analysing the data on transverse momentum spectra within a unified model for chemical and kinetic freezeout. The study has been done within two different schemes of freezeout, single freezeout where all the hadrons freezeout together versus double freezeout where those hadrons with non zero strangeness content have different freezeout parameters compared to the nonstrange ones. We demonstrate that the data is better described within the latter scenario with a strange freezeout hypersurface which is smaller in volume and hotter compared to the non-strange freezeout hypersurface for all centralities with a reduction in χ/Ndf around 40%. PACS numbers:12.38.Mh, 25.75.-q, 25.75.Dw, 25.75.Ld
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.
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.
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.
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.