Searching for curvature pion radiation from protons in strongly magnetized pulsars

TL;DR

This paper investigates the potential for curvature pion radiation from protons in strongly magnetized pulsars, identifying conditions under which such signals could be detectable, with implications for high-energy astrophysics.

Contribution

It introduces a method to estimate the likelihood of curvature pion radiation in pulsars and identifies specific pulsar parameters needed for observable signals.

Findings

The pulsar J0537-6910 is the best candidate but unlikely to produce observable signals.

Pulsars with a 1 ms period and magnetic field around 10^{12} G could generate detectable curvature pion radiation.

Other emission processes in pulsar magnetospheres are also discussed.

Abstract

By using rather conservative estimates based on the simplest polar cap model, we search the ATNF Pulsar Catalogue for strongly magnetized stars that could accelerate relativistic protons up to the curvature pion production threshold. The best candidate turns out to be the 16 ms pulsar J0537-6910, but the corresponding characteristic parameter $\chi=a/m_p$ is yet too small to give origin to observable signals. We show that, for pulsars with period $P\approx 1\,$ms, a surface polar magnetic field $B \approx 10^{12}$G is required in order to induce detectable curvature pion radiation from accelerated protons in the magnetosphere. Some other emission processes are also considered.