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Updated: Jun 8, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Constraints on Symmetric Dark Matter from Neutron Star Capture and Collapse
Yuxin Liu1, Zhen Liu2, Maxim Pospelov2,3
1International Center for Theoretical Physics Asia-Pacific (ICTP-AP), University of Chinese Academy of Sciences (UCAS), Beijing 100190, China.
Physical Review Letters
|June 7, 2026
Summary
New research shows dark matter (DM) capture by neutron stars (NSs) can be asymmetric, even with symmetric DM populations. This finding broadens constraints on DM models, impacting our understanding of cosmic structure formation.
Area of Science:
- * Particle Physics and Astrophysics: Investigating the nature and interactions of dark matter.
- * Cosmology: Understanding the formation and evolution of the universe.
Background:
- * Existing constraints on dark matter (DM) models rely on the assumption of symmetric DM populations and conserved particle-antiparticle number, challenged by neutron star (NS) collapse.
- * Previous studies focused on asymmetric DM abundances (nχ≠nχ˜) to explain NS stability.
Purpose of the Study:
- * To demonstrate that constraints on DM models extend to symmetric DM populations (nχ=nχ˜).
- * To explore the mechanism of asymmetric DM capture via nucleon-DM scattering, even when DM populations are symmetric.
Main Methods:
- * Analysis of DM capture rates regulated by nucleon-DM scattering, considering interference effects in χ-n interactions.
- * Examination of charge conjugation (Cχ) and combined parity (Pχ+n) properties of DM-nucleon interactions.
- * Utilizing canonical neutron star parameters and local dark matter halo inputs.
Main Results:
- * Asymmetric DM capture (σχn≠σχ˜n) is shown to be a generic feature induced by interference effects in DM-nucleon interactions.
- * Exclusion of spin-averaged scattering cross sections down to σnχ≳10⁻⁴⁶ cm² for DM masses mχ≲10¹⁰ GeV.
- * Constraints are shown to persist even for small cross-section asymmetries (A≳10⁻⁵).
Conclusions:
- * The study significantly broadens the applicability of neutron star constraints to a wider range of dark matter models, including those with symmetric DM populations.
- * The findings necessitate a re-evaluation of existing dark matter constraints and highlight the importance of considering interaction asymmetries.
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