The 26Al Production of the ν e -process in the Explosion of Massive Stars

Abstract

The core collapses of massive stars at the ends of their lives will produce powerful streams of neutrinos, which provide an important contribution to the 26Al yield during the explosion stage. In this work, the contribution of the process to the radioactive 26Al in the Milky Way is studied based on a simple model. By combining the calculation of the neutrino-nucleus cross section and some hypotheses about core-collapse supernova explosions, the ratio of 26Al and 26Mg of the ν e -process is estimated. An analytical relationship between the 26Mg yield and the initial mass and metallicity of massive stars is then obtained, making it easy to estimate the 26Mg and 26Al yields analytically. Due to the simplicity of the model, we can move away from complex calculations and into a careful study of the effects of some important factors, such as the radius of the O/Ne shell, the shock velocity, the neutrino spectrum, the Galactic mass and metallicity distribution, and so on. The uncertainties of the 26Al yield contributed from these factors are discussed in detail. This study will facilitate an intuitive understanding of the buried implicit assumptions in previous studies.