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Updated: Oct 23, 2025
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Neutron Star Internal Heating Constraints on Mirror Matter
David McKeen1, Maxim Pospelov2,3, Nirmal Raj1
1TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada.
Physical Review Letters
|August 23, 2021
Summary
We found that neutron star temperatures can constrain mirror neutrons. Neutron-mirror-neutron mixing causes heating, providing new limits on this dark matter candidate.
Area of Science:
- Astrophysics
- Particle Physics
Background:
- Mirror sectors are theoretical constructs proposed to explain phenomena like dark matter and the neutron lifetime anomaly.
- Neutron stars offer a unique environment to study fundamental physics due to their extreme conditions.
Purpose of the Study:
- To investigate neutron star temperatures as a probe for mirror neutrons.
- To derive constraints on neutron-mirror-neutron mixing using thermal emissions from cold neutron stars.
Main Methods:
- Analyzing thermal emissions from the coldest known neutron star, PSR 2144-3933.
- Modeling the heating mechanism resulting from neutron-to-mirror-neutron conversion within neutron star cores.
Main Results:
- A new constraint on the strength of neutron-mirror-neutron mixing was derived.
- The derived limits are competitive with laboratory searches and extend to a significantly larger range of mass splittings.
Conclusions:
- Neutron star thermal emissions provide a powerful new method to search for mirror neutrons.
- This mechanism is relevant for other neutron disappearance channels and is a target for future UV, optical, and IR telescopes.
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