Equation of state of strongly interacting matter and intensity interferometry of thermal photons

We find that an equation of state (EOS) for hot hadronic matter consisting of all mesons (baryons) having M<1.5(2.0)GeV along with Hagedorn resonances in thermal and chemical equilibrium, matches rather smoothly with lattice EOS (p4 action, Nτ=8) for T up to ≈200 MeV, when corrections are made for the finite volume of hadrons. Two equations of state, HHL and HHB are constructed where the above is matched to the lattice and bag model EoS respectively at a critical temperature Tc=165MeV. We find that the particle and thermal photon spectra differ only marginally for the two equations of state at both RHIC and LHC energies. The intensity interferometry results, specially the outward correlations for thermal photons are found to be quite distinct for the two equations of state.