Rapidity distribution of photons emitted from a hadronizing quark-gluon plasma.
The rapidity distribution of thermal photons emitted from a hadronizing quark-gluon plasma is obtained with initial conditions locally determined from the hadronic rapidity density and assuming a longitudinal scaling expansion as in Bjorken hydrodynamics. The corresponding results for direct (QCD) photons and for decay photons are also obtained. The rapidity distributions of the three types of photons are found to be quite different and may help identify the most favorable window in the momentum space for identification for the quark-gluon plasma

title: Vector and axial-vector mesons at finite temperature
abstract: We consider the thermal correlation functions of vector and axial-vector currents and evaluate corrections to the vector and axial-vector meson pole terms to one loop in chiral perturbation theory. As expected, the pole positions do not shift to leading order in temperature. But the residues decrease with temperature. We review briefly other methods in the literature to determine these pole parameters. We find our evaluation to disprove a result on the mixing of the correlation functions at finite temperature.

title: Viscous Coefficients of a Hot Pion Gas
abstract: The steps essentially involved in the evaluation of transport coefficients in linear response theory 
using Kubo formulas are to relate the defining retarded correlation function to the corresponding 
time-ordered one and to evaluate the latter in the conventional perturbation expansion. Here we 
evaluate the viscosities of a pion gas carrying out both the steps in the real-time formulation. We 
also obtain the viscous coefficients by solving the relativistic transport equation in the Chapman-Enskog approximation to leading order. An in-medium cross-section is used in which spectral 
modifications are introduced in the propagator of the exchanged .

title: Thermal photons to dileptons ratio at LHC
abstract: It is shown that the ratio of transverse momentum (p_T) distribution of thermal photons to dileptons produced in heavy ion collisions reaches a plateau above p_T=1 GeV. We argue that the value of the ratio in the plateau region can be used to estimate the initial temperature.

title: Electromagnetic radiation from hot and dense hadronic matter
abstract: The modifications of hadronic masses and decay widths at finite temperature and baryon density are investigated using a phenomenological model of hadronic interactions in the Relativistic Hartree Approximation. We consider an exhaustive set of hadronic reactions and vector meson decays to estimate the photon emission from hot and dense hadronic matter. The reduction in the vector meson masses and decay widths is seen to cause an enhancement in the photon production. It is observed that the effect of p -decay width on photon spectra is negligible. The effects on dilepton production from pion annihilation are also indicated.

title: Matter-induced charge symmetry breaking and the pion form factor in nuclear medium
abstract: Medium modification of the pion form factor has been evaluated in asymmetric nuclear matter (ANM). It is shown that both the shape and the pole position of the pion form factor in dense asymmetric nuclear matter is different from its vacuum counterpart with ρ–ω mixing. This is due to the density and asymmetry-dependent ρ–ω mixing which could even dominate over its vacuum counterpart in matter. Results are presented for an arbitrarily mixing angle. The effect of the in-medium pion factor on experimental observables, e.g., invariant mass distribution of lepton pairs has been demonstrated.

title: Generalized two-angle parametrization of the Cabibbo-Kobayashi-Maskawa matrix.
abstract: We demonstrate how to parametrize the Cabibbo-Kobayashi-Maskawa (CKM) matrix in terms of its eigenvalues and eigenvectors, generalizing a recent idea of Kielanowski's. In this version we are able to reproduce a symmetric CKM matrix with only two angles while predicting a range in the amount of {ital CP} violation. The relation between this parametrization and the standard one is studied. Some variations of this parametrization are worked out.

title: Naturally light Majorana neutrinos with no neutrinoless double- beta decay.
abstract: It is argued that neutrinoless double-{beta} decay (({beta}{beta}){sub 0{nu}}) does not depend on the physical Dirac or Majorana mass of the electron neutrino. A new scenario is proposed where the physical neutrino can naturally be a light Majorana particle, without any ({beta}{beta}){sub 0{nu}}. Supersymmetric grand unified theories are constructed incorporating this scenario.