Limits on self-interacting dark matter from neutron stars

Area of Science:

• * Particle Physics and Astrophysics
• * Cosmology and Dark Matter Research

Background:

• * Asymmetric dark matter models propose distinct particle properties.
• * Neutron stars are dense remnants of stellar evolution.
• * Self-interactions of dark matter particles are a key area of theoretical study.

Purpose of the Study:

• * To constrain the self-interaction properties of fermionic asymmetric dark matter.
• * To investigate the astrophysical implications of dark matter accretion in neutron stars.

Main Methods:

• * Analysis of observational data from nearby old neutron stars.
• * Theoretical modeling of WIMP (Weakly Interacting Massive Particle) accretion and collapse within neutron stars.
• * Derivation of constraints on WIMP self-interaction cross-sections.

Main Results:

• * Severe constraints are placed on WIMP self-interactions, particularly those mediated by Yukawa-type forces.
• * Even in low dark matter density regions, neutron stars can accrete sufficient WIMPs to trigger gravitational collapse.
• * Derived constraints are significantly stricter than those obtained from previous studies, such as the Bullet Cluster.

Conclusions:

• * Neutron star observations provide powerful new limits on dark matter self-interactions.
• * The potential for WIMP self-interactions to induce mini black hole formation and neutron star destruction is highlighted.
• * This study refines our understanding of dark matter properties and its astrophysical impact.