Supernova axion emissivity with ?(1232) resonance in heavy baryon chiral perturbation theory

In this paper, we evaluate the energy loss rate of supernovae induced by the axion emission process pi- +p -n + a with the Delta(1232) resonance in the heavy baryon chiral perturbation theory for the first time. Given the axion-nucleon-Delta interactions, we include the previously ignored Delta-mediated graphs to the pi- + p -n + a process. In particular, the Delta 0-mediated diagram can give a resonance contribution to the supernova axion emission rate when the center-of-mass energy of the pion and proton approaches the Delta(1232) mass. With these new contributions, we find that for the typical supernova temperatures, compared with the earlier work with the axion-nucleon (and axion-pion-nucleon contact) interactions, the supernova axion emissivity can be enhanced by a factor of similar to 4(2) in the Kim-Shifman-Vainshtein-Zakharov model and up to a factor of similar to 5(2) in the Dine-Fischler-Srednicki-Zhitnitsky model with small tan beta values. Remarkably, we notice that the Delta(1232) resonance gives a destructive contribution to the supernova axion emission rate at high supernova temperatures, which is a nontrivial result in this study.