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Updated: Nov 15, 2025
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Hyperpolarized Xenon for NMR and MRI Applications
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Enhanced Supernova Axion Emission and Its Implications.
Pierluca Carenza1,2, Bryce Fore3,4, Maurizio Giannotti5
1Dipartimento Interateneo di Fisica "Michelangelo Merlin," Via Amendola 173, 70126 Bari, Italy.
Physical Review Letters
|March 5, 2021
Summary
We calculated axion emission rates from thermal pions in supernovae and neutron star mergers. This process is much larger than previously thought, offering new ways to detect QCD axions.
Area of Science:
- Astrophysics
- Particle Physics
- Nuclear Physics
Background:
- Axion emission from astrophysical events is crucial for understanding fundamental physics.
- Nucleon-nucleon bremsstrahlung was considered the dominant axion production mechanism.
Purpose of the Study:
- To calculate the axion emission rate from thermal pion interactions.
- To identify unique spectral features of these axions.
- To explore astrophysical and particle physics implications.
Main Methods:
- Calculations of axion emission rates from pion interactions in dense matter.
- Analysis of the resulting axion spectrum.
- Comparison with nucleon-nucleon bremsstrahlung.
Main Results:
- Axion emission rate from thermal pions is 2-5 times larger than nucleon-nucleon bremsstrahlung.
- The axion spectrum is significantly harder (higher energies).
Conclusions:
- Pion-induced axion emission is a dominant process in supernovae and neutron star mergers.
- These findings provide a stronger constraint on the QCD axion mass.
- Enhanced prospects for direct axion detection using neutrino detectors during supernovae.
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