Importance of constraining the dense matter Equation of State in pulsar astrophysics

TL;DR

This paper investigates how the choice of dense matter Equation of State affects the estimated surface magnetic fields of pulsars, revealing significant variations that impact models of pulsar magnetospheres and suggesting new ways to constrain the Equation of State.

Contribution

It demonstrates the dependence of pulsar magnetic field estimates on the Equation of State and provides a method to better constrain these equations through magnetic field measurements.

Findings

Magnetic field estimates can vary by an order of magnitude.

Significant differences found in the magnetic field of PSR J0737-3039A.

Highlighting the importance of constraining the dense matter Equation of State.

Abstract

We study the dependence of the surface magnetic fields of radio pulsars on the choice of Equations of State, pulsar masses and the values of the angle between the magnetic axis and the spin axis of the pulsars within simple dipole model. We show that the values of the surface magnetic field can be even order of magnitude different from its canonical values. This difference will effect any magnetosphere related model to explain observational features of radio pulsars and magnetars. We find a significant difference of the value of the surface magnetic field from the commonly quoted value for the faster member of the double pulsar system, i.e. PSR J0737-3039A as here both the mass of the pulsar and the angle between the magnetic axis and the spin axis are known. Our study reveals the importance of constraining the dense matter Equations of State in pulsar astrophysics as well as hints an alternative way to constrain these by independent determination of the pulsar magnetic field.