Variational Theory of Hot Dense Matter

We develop a variational theory of hot nuclear matter in neutron stars and supernovae. It can also be used to study charged, hot nuclear matter which may be produced in heavy-ion collisions. This theory is a generalization of the variational theory of cold nuclear and neutron star matter based on realistic models of nuclear forces and pair correlation operators. The present approach uses microcanonical ensembles and the variational principle obeyed by the free energy. We show that the correlated states of the microcanonical ensemble at a given temperature T and density rho can be orthonormalized preserving their diagonal matrix elements of the Hamiltonian. This allows for the minimization of the free energy without corrections from the nonorthogonality of the correlated basis states, similar to that of the ground state energy. Samples of the microcanonical ensemble can be used to study the response, and the neutrino luminosities and opacities of hot matter. We present methods to orthonormalize the correlated states that contribute to the response of hot matter. We apply this variational theory to symmetric nuclear matter and pure neutron matter. This extension generalizes to finite temperatures, the many body technique used in the construction of the zero temperature Akmal-Pandharipande-Ravenhall equation of state. We discuss how the formalism can be used for practical calculations of hot dense matter. Our calculations are a significant improvement over the previous calculation due to Friedman and Pandharipande. The Hamiltonian contains modern realistic two nucleon and three nucleon interactions along with relativistic boost corrections. Expectation values of various operators, including the Hamiltonian, are calculated using cluster expansion and chain summation techniques. The pair correlation operator is now calculated at every density and temperature. Neutral pion condensation along with the associated isovector spin longitudinal sum rule is analyzed. The equation of state is calculated for temperatures less than 30 MeV and densities less than three times the saturation density of nuclear matter. The behavior of the nucleon effective mass in medium is also discussed.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Mukherjee, Abhishek

Contributors dc:contributor

• Ceperley, David M.

• Physics, Astronomy and Astrophysics

Language dc:language

eng

Identifier

(MiAaPQ)AAI3392231

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/80617