Probing phase transitions in a pulsar core through the observable effects on pulse profile modulation

Abstract

There are compelling arguments in favour of various baryon-rich exotic QCD phases in the core of a pulsar. We suggested a technique to probe such phases by studying the effects of phase transition-induced density fluctuations on pulse profile modulation. Such density fluctuations cause the initial moment of inertia tensor (MI) of an oblate shape pulsar to get random additional contributions for each component. These contributions are assumed to be Gaussian of width , which characterizes the strength of density fluctuations. Using sample values of and the pulsar’s deformation parameter , we solve Euler’s equations for the rotational dynamics of the pulsar to observe the effects of wobbling through the modifications of pulse profiles. Our results show a specific pattern in the perturbed pulses. The wobbling of the pulsar dies away once the density fluctuations fade away. This feature distinguishes the transient pulse modulations from the pre-existing wobbling. The decay time of these modulations, being directly related to the relaxation time of density fluctuations, it provides valuable information about the nature of phase transition.