Axionlike particles (ALPs) coupled to nucleons can be efficiently produced in core-collapse supernovae (SNe) and then, if they couple to photons, convert into gamma rays in cosmic magnetic fields, generating short gamma-ray bursts. Though ALPs from a Galactic SN would induce an intense and easily detectable gamma-ray signal, such events are exceedingly rare. In contrast, a few SNe per year are expected in nearby galaxies within ∼O(10) Mpc, where strong magnetic fields can enable more efficient ALP-photon conversions than in the Milky Way, offering a promising extragalactic target. This circumstance motivates full-sky gamma-ray monitoring, ideally combined with decihertz gravitational-wave detectors to enable time-triggered searches from nearby galaxies. We show that, under realistic conditions, a decade of coverage could reach sensitivities to the product of the ALP-proton and ALP-photon couplings gap × gaγ ≳ 10−24 GeV−1 for ALP masses ma ≲ 10−9 eV. This sensitivity would allow one to probe a large, currently unexplored region of the parameter space below the long-standing SN 1987A bound.
Detecting light axions from supernovae in nearby galaxies
Lecce F.;Mirizzi Alessandro
2026-01-01
Abstract
Axionlike particles (ALPs) coupled to nucleons can be efficiently produced in core-collapse supernovae (SNe) and then, if they couple to photons, convert into gamma rays in cosmic magnetic fields, generating short gamma-ray bursts. Though ALPs from a Galactic SN would induce an intense and easily detectable gamma-ray signal, such events are exceedingly rare. In contrast, a few SNe per year are expected in nearby galaxies within ∼O(10) Mpc, where strong magnetic fields can enable more efficient ALP-photon conversions than in the Milky Way, offering a promising extragalactic target. This circumstance motivates full-sky gamma-ray monitoring, ideally combined with decihertz gravitational-wave detectors to enable time-triggered searches from nearby galaxies. We show that, under realistic conditions, a decade of coverage could reach sensitivities to the product of the ALP-proton and ALP-photon couplings gap × gaγ ≳ 10−24 GeV−1 for ALP masses ma ≲ 10−9 eV. This sensitivity would allow one to probe a large, currently unexplored region of the parameter space below the long-standing SN 1987A bound.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
