On the birthrates of Galactic neutron stars

TL;DR

This paper examines the discrepancy between the observed birthrates of various Galactic neutron star populations and the Galactic supernova rate, exploring potential solutions and evolutionary scenarios to resolve the inconsistency.

Contribution

It provides a comprehensive review of neutron star birthrate estimates and discusses possible reasons for their mismatch with supernova rates, including overestimations and evolutionary links.

Findings

Current estimates may overstate neutron star birthrates.

The supernova rate may be insufficient to produce all observed neutron star populations.

Evolutionary scenarios could explain the birthrate discrepancy.

Abstract

In light of the recently discovered neutron star populations we discuss the various estimates for the birthrates of these populations. We revisit the question as to whether the Galactic supernova rate can account for all of the known groups of isolated neutron stars. After reviewing the rates and population estimates we find that, if the estimates are in fact accurate, the current birthrate and population estimates are not consistent with the Galactic supernova rate. We discuss possible solutions to this problem including whether or not some of the birthrates are hugely over-estimated. We also consider a possible evolutionary scenario between some of the known neutron star classes which could solve this potential birthrate problem.