Supernova bounds on nucleonphilic ALPs

Axion-like particles (ALPs) coupled to nucleons might be copiously emitted from a supernova core. This work is devoted to the extension of existing bounds on free-streaming ALPs to the case in which these are so strongly-interacting with the nuclear matter to be trapped in the SN core. From SN 1987A neutrino burst observations, two different arguments have been considered to constrain the ALP parameter space: the cooling criterium and the absence of an ALP-induced signal in Kamiokande-II neutrino detector. These lead to the exclusion of ALP-nucleon coupling g₀₍10^-9 for ALP masses mₐ 1\, MeV. Remarkably, in the case of canonical QCD axion models, the SN bounds exclude all values of mₐ 10^-2 eV. This result prevents the possibility for current and future cosmological surveys to detect any signatures due to hot dark matter QCD axion mass.