Pulsar Sparking: What if mountains on the surface?

TL;DR

This paper introduces a numerical framework to analyze how small mountains on pulsar surfaces influence the vacuum gap and magnetospheric activity, potentially explaining phenomena in pulsars below the traditional death line.

Contribution

It presents a novel computational model linking surface topography of pulsars to their magnetospheric behavior and suggests solid strangeon matter as a basis for stable surface mountains.

Findings

Small mountains significantly affect vacuum gap properties.

Pulsars with surface mountains can explain certain observed pulsar phenomena.

Surface topography may depend on the state of supranuclear matter.

Abstract

A numerical framework to calculate the height and potential of the vacuum inner gap of pulsars is presented here. % The results demonstrate that small mountains on a pulsar's polar cap tend to significantly influence the properties of the inner vacuum gap, making it easier for sparks to form. % In this scenario, the magnetospheric activity observed from the pulsars PSR J0250$+$5854 and PSR J2144$-$3933 which lie below the traditional pulsar death line, and some single-pulse modulation phenomena could also then be understood. % Furthermore, the presence of small mountains should depend on the puzzling state of supranuclear matter inside pulsars. % In order to sustain stable mountains on the surface, pulsars might be made of solid strangeon matter, which is favoured by both the charge neutrality and the flavour symmetry of quarks.