Nuclear reaction rates governing the nucleosynthesis of 44Ti

✍ Scribed by Liping Jin; Bradley S. Meyer; Lih-Sin The; Donald D. Clayton

• Book ID: 104336465
• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 180 KB
• Volume: 621
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/s0375-9474(97)00263-7

✦ Synopsis

It appears that the main mechanism of 44Ti nucleosynthesis in supernovae involves an alpha-rich freezeout of hot matter. Late assembly of x2C nuclei via triple alpha reactions is followed by a rapid sequence of captures upward to the 44Ti. Considering that radioactive 44Ti is one of the premier targets of gamma astronomy, having already been detected in the Cas A remnant by COMPTEL, and considering that this sequence appears to be responsible for the large 44Ca abundance in solar matter and for the huge 4aCa excesses found within meteoritic SUNOCONs, we have surveyed the nuclear reaction rate uncertainties that govern this abundance. Our purpose is to identify for the nuclear physics community those reaction rates that have the greatest astrophysical importance. Using a large nuclear reaction network, we have systematically varied cross sections and groups of cross sections in an experimental test for astrophysical significance. We will identify these most important nuclear rates and explain our understanding of the overall rate dependencies that we have found.