New class of compact stars: Pion stars

Understand

We investigate the viability of a new type of compact star whose main constituent is a Bose-Einstein condensate of charged pions.

• Several different setups are considered, where a gas of charged leptons and neutrinos is also present.
• The pionic equation of state is obtained from lattice QCD simulations in the presence of an isospin chemical potential, and requires no modeling of the nuclear force.
• The gravitationally bound configurations of these systems are found by solving the Tolman-Oppenheimer-Volkov equations.