Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles
Abstract
We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling:
- Publication:
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Journal of Cosmology and Astroparticle Physics
- Pub Date:
- February 2015
- DOI:
- 10.1088/1475-7516/2015/02/006
- arXiv:
- arXiv:1410.3747
- Bibcode:
- 2015JCAP...02..006P
- Keywords:
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- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Phenomenology
- E-Print:
- Accepted for publication in JCAP (December 22nd, 2014)