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Title: Single Millisecond Pulsars from Dynamical Interaction Processes in Dense Star Clusters
Abstract Globular clusters (GCs) are particularly efficient at forming millisecond pulsars. Among these pulsars, about half lack a companion star, a significantly higher fraction than in the Galactic field. This fraction increases further in some of the densest GCs, especially those that have undergone core collapse, suggesting that dynamical interaction processes play a key role. For the first time, we createN-body models that reproduce the ratio of single-to-binary pulsars in Milky Way–like GCs. We focus especially on NGC 6752, a typical core-collapsed cluster with many observed millisecond pulsars. Previous studies suggested that an increased rate of neutron star binary disruption in the densest clusters could explain the overabundance of single pulsars in these systems. Here, we demonstrate that binary disruption is ineffective and instead we propose that two additional dynamical processes play dominant roles: (1) tidal disruption of main-sequence stars by neutron stars and (2) gravitational collapse of heavy white dwarf binary merger remnants. Neutron stars formed through these processes may also be associated with fast radio bursts similar to those observed recently in an extragalactic GC.  more » « less
Award ID(s):
2108624
PAR ID:
10543556
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
961
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
98
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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