Markov chain Monte Carlo population synthesis of single radio pulsars in the Galaxy

TL;DR

This paper develops a comprehensive model for the evolution of solitary neutron stars, incorporating various physical processes and selection effects, and uses MCMC to optimize parameters, predicting future survey discoveries.

Contribution

It introduces a detailed population synthesis model for single radio pulsars, including magnetic decay and Galactic motion, optimized with MCMC, and predicts survey yield increases.

Findings

Preferred magnetic field decay scale of ~4.27 Myr

Predicted 23-137% increase in known pulsars with SKA surveys

Model parameters show correlation between magnetic decay and radio luminosity

Abstract

We present a model of evolution of solitary neutron stars, including spin parameters, magnetic field decay, motion in the Galactic potential and birth inside spiral arms. We use two parametrizations of the radio-luminosity law and model the radio selection effects. Dispersion measure is estimated from the recent model of free electron distribution in the Galaxy (YMW16). Model parameters are optimized using the Markov Chain Monte Carlo technique. The preferred model has a short decay scale of the magnetic field of 4.27 +0.4 -0.38 Myr. However, it has non-negligible correlation with parameters describing the pulsar radio luminosity. Based on the best-fit model, we predict that the Square Kilometre Array surveys will increase the population of known single radio pulsars by between 23 and 137 per cent. The Indri code used for simulations is publicly available to facilitate future population synthesis efforts.