Probing dynamics of phase transitions occurring inside a pulsar

Abstract

During the evolution of a pulsar, various phase transitions may occur in its dense interior, such as superfluid transition, as well as transition to various exotic phases of quantum chromodynamics (QCD). We propose a technique which allows to probe these phases and associated transitions by detecting changes in rotation of the star arising from density changes and fluctuations during the transition affecting stars moment of inertia (MI). Our results suggest that these changes may be observable, and may possibly account for glitches and anti-glitches. Accurate measurements of pulsar timing and intensity modulations (from wobbling) may be used to pin down the particular phase transition occurring inside the pulsar core. We also discuss the possibility of observing gravitational waves from the changes in the quadrupole moment (QM) arising from these rapidly evolving density fluctuations.