T-2, Nuclear and Particle Physics, Astrophysics and Cosmology

A pion condensate as a more favorable ground state of high density neutron matter via the auxiliary field GFMC method

Mohamed Bouadani
Arizona State Univ.

A Pion Condensate in dense nuclear matter may occur in the inner core of neutron stars. The FHNC/SOC of Akmal-Pandharipande show a "pion-excess" response that was attributed to a pion condensate. The present calculation aim to show the ground state of a spin density wave, representing the pion condensate, is lower than a liquid phase energy. The computation uses the auxiliary field GFMC method with fixed phase constraint for a realistic hamiltonian that has the argonne v8′ potential for two-body interaction with the urbanna UIX potential for three-body interaction. Neutrons fill closed shells in a periodic box. The energy difference is about 6% at a density, ρ, about five times the nuclear equilibrium density, ρo. The phase transition seems to be of second-order kind with an estimated critical density ρc / ρo ~ 3.1 and spin-density wavelength λc ~ 2.8 fm.


Contact Us | Careers | Bradbury Science Museum | Emergencies | Inside LANL | Maps | Site Feedback | SSL Portal | Training

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA© Copyright 2010-11 LANS, LLC All rights reserved | Terms of Use | Privacy Policy