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We discuss the possibility to probe the QCD critical point during the prompt black hole formation. In black hole formation processes, temperature and baryon chemical potential become as high as T ∼ 90MeV and μB ∼ 1300MeV. This high baryon chemical potential would allow nuclear matter to experience the QCD phase transition, and the temperature may be higher than the QCD critical point temperature. We compare the phase boundary in chiral effective models and the thermal environment obtained in the ν radiation hydrodynamical calculation of the gravitational collapse of a 40M⊙ star leading to the black hole formation. This comparison suggests that quark matter is likely to be formed, and the QCD critical point may be swept. [ABSTRACT FROM AUTHOR]

The mean-field approximation predicts pairing and shape phase transitions in nuclei as a function of temperature or excitation energy. However, in the finite nucleus the singularities of these phase transitions are smoothed out by quantal and thermal fluctuations. An interesting question is whether signatures of these transitions survive despite the large fluctuations. The shell model Monte Carlo (SMMC) approach enables us to calculate the statistical properties of nuclei beyond the meanfield approximation in model spaces that are many orders of magnitude larger than spaces that can be treated by conventional diagonalization methods. We have extended the SMMC method to heavy nuclei and used it to study the transition from vibrational (spherical) to rotational (deformed) nuclei in families of rare-earth isotopes. We have calculated collective enhancement factors of level densities as a function of excitation energy and found that the decay of the vibrational and rotational enhancements is well correlated with the pairing and shape phase transitions, respectively. [ABSTRACT FROM AUTHOR]

Improving the up-conversion efficiency is the key issue in tellurite glasses. The quantum efficiency, radiative transition rate and lifetimes of excited states are greatly influenced by the optical properties of the host material, ligand field, multiphonon relaxation processes, impurities, temperature and concentration of erbium ions. We develop a comprehensive 4-level model to examine the radiative and nonradiative (NR) decay processes for the green (4S3/2→4I15/2) and red (4F9/2→4I15/2) emission over a temperature range of (10-340 K) and concentration range of (0.1-4.5 mol.%). Concentration dependent enhancement and thermal quenching of efficiency for up-conversion is investigated using the derived rate equations. These features are attributed to the NR energy transfer processes, trapped impurity effects, and thermal assisted hopping. The unusual nature of temperature and concentration dependent quenching effects for green and red emission is queries for further investigations. It is further suggested that to achieve higher infrared to visible up-converted efficiency in tellurite glasses the NR channels for energy and charge transfer by phonon and impurity mediated process has to be minimized. Our results on pump power dependent emission intensity, quantum efficiency, luminescence intensity, radiative lifetimes, and transition probabilities are in conformity with other experimental findings. [ABSTRACT FROM AUTHOR]

Spectral profiles and lifetimes have been calculated for the He(21S)-Ne loosely bound molecule. It has been found that the radiating properties of the molecule depend strong on temperature. [ABSTRACT FROM AUTHOR]

We point out that higher order cumulants of net-charge fluctuations are particularly sensitive to critical behavior and may allow to clarify whether chemical freeze-out observed in heavy ion collisions happens in the vicinity of a critical point. A systematic analysis allows of different cumulants allows to quantify to what extent the chiral transition at vanishing quark masses impacts thermodynamics at the crossover transition as well as on the freeze-out line. [ABSTRACT FROM AUTHOR]

We discuss chiral and deconfinement aspects of the finite temperature transition in QCD using improved staggered actions. We study the cutoff dependence of the renormalized chiral condensate and Polyakov loop. [ABSTRACT FROM AUTHOR]

Results will be presented from a study of the QCD transition region using 2 + 1 flavors of fermions and a dislocation suppressing gauge action on a lattice with temporal extent of 8 and spatial extent 16 (1.9 - 2.7 fm). A series of temperatures from 140 through 200 MeV, separated by 10 MeV have been studied. All the simulations lie on a line of constant physics with 200 MeV pions, realized using domain wall fermion, a chirally symmetric fermion formulation. The chiral condensates, susceptibility, anomalous symmetry breaking and a detailed study of the Dirac spectrum will be described and compared with earlier staggered results. [ABSTRACT FROM AUTHOR]