Speaker
Description
Mean-field model quantum field theories of hadrons were traditionally developed to describe
cold and dense nuclear matter and are by now very well constrained
from the recent neutron star merger observations. We show that when
augmented with additional known hadrons and resonances
but not included earlier, these mean-field models can be extended beyond
its regime of applicability. Calculating some specific ratios of baryon
number susceptibilities for finite temperature and moderate values of
baryon densities within mean-field approximation, we show that these match
consistently with the lattice QCD data available at lower densities, unlike
the results obtained from a non-interacting hadron resonance gas model. We also estimate the
curvature of the line of constant energy density, fixed at its corresponding value
at the chiral crossover transition in QCD, in the temperature-density plane. The
number density at low temperatures and high density is found to be about twice the
nuclear saturation density along the line of constant energy density of $\epsilon=348
\pm 41$ MeV/$\text{fm}^3$. Moreover from this line we can indirectly constrain the
critical end-point of QCD to be beyond $\mu_B=596$ MeV for temperature $\sim 125 $ MeV.