Revisiting Supernova 1987A Limits on Axion-Like-Particles

Abstract

Using recent supernova models, I revisit the Supernova 1987a constraints on scalar/pseudoscalar Axion-Like-Particles (ALPs). On the basis of the neutrino detections, the luminosity of ALPs must be $\lesssim 5\times10^{52} \,\mathrm{erg}/s$ after the core-bounce, and this bound limits ALPs couplings. Contrary to the QCD axion models where all couplings are $\sim 1/f_a$, it has been shown recently that a radion/dilaton could have far different coupling strength to photons and to nucleons. This fact has raised a need to establish the limits on each coupling independently. The bounds from ALPs emission by nucleon-nucleon bremsstrahlung through a two-nucleon coupling and by the Primakoff process through a two-photon coupling are updated considering the total volume emission. I find the bounds on the two-photon coupling from the Primakoff process differ from previous bounds by an order of magnitude. Through the volume emission study, trapping regimes for $m_a\gtrsim10\,\mathrm{MeV}$ are also alleviated, which need to be probed by future experiments.