Orbital eccentricity of binary radio pulsars in globular clusters and interaction between stars

TL;DR

This study investigates the orbital eccentricities of binary radio pulsars in globular clusters, revealing how different stellar interactions influence their orbital characteristics through computational simulations.

Contribution

It introduces a detailed simulation approach to understand how stellar interactions shape pulsar binary eccentricities in globular clusters.

Findings

Fly-by interactions explain intermediate eccentricities.

Exchanges and mergers lead to very high eccentricities.

Local stellar density affects eccentricity distribution.

Abstract

We analyze the observed distribution of the orbital eccentricity and period of binary radio pulsars in globular clusters using computational tools to simulate binary-single star interactions. Globular clusters have different groups of pulsars arising from separate interaction scenarios. Intermediate eccentricities of cluster pulsars can be mostly accounted by fly-bys although locally lower stellar densities at pulsar positions may alter the situation. Very high eccentricities are likely to be results of exchanges and/or mergers of single stars with the binary companion of the pulsar.