Probing Dynamics of Phase Transitions occurring inside a Pulsar

TL;DR

This paper proposes a method to detect internal phase transitions in pulsars through changes in their rotation and gravitational wave emissions, potentially explaining observed glitches and anti-glitches.

Contribution

It introduces a novel technique to probe pulsar interior phases by analyzing rotational and gravitational wave signals related to density fluctuations.

Findings

Changes in pulsar rotation may indicate internal phase transitions.

Timing and intensity modulations can identify specific core phases.

Gravitational waves from density fluctuations are potentially observable.

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 star's moment of inertia. Our results suggest that these changes may be observable, and may possibly account for glitches and (recently observed) anti-glitches. Accurate measurements of pulsar timing and intensity modulations (arising from wobbling of star due to development of the off-diagonal components of moment of inertia) 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 arising from these rapidly evolving density fluctuations.