Explosive neon burning and Al-26 gamma-ray astronomy

Abstract

The nucleosynthesis that occurs when the neon-rich layers of a massive highly evolved star are shock heated to high temperature is examined for peak temperatures in the range of 1.0 to 3.2 x 10 to the 9th deg K. Emphasis is placed on the production of the radioactive isotope Al-26; in addition, calculations indicate that at the time of aluminum synthesis in supernovae the (Al-26)/(Al-27) ratio was near 10 to the -3rd power. It is found that a combination of hydrostatic carbon burning and explosive neon burning, averaged over a continuous distribution of explosion temperatures, produces those isotopes traditionally assigned to explosive carbon burning in amounts that agree with solar values as well as or better than the nucleosynthesis from explosive carbon burning itself.