Nuclear Seminar

Two key radioactive isotopes of gamma-ray astronomy: the past, present, and future of Al26 and Fe60

Dr. Frank Timmes
Los Alamos National Laboratory

Monday, September 17, 2007   4:00 p.m.   NSH 124
(Refreshments served prior to seminar in NSH 124)

Radioactive isotopes are common by-products of nucleosynthesis in stellar sources and constitute important probes of the underlying physical processes since they can be studied through their characteristic gamma-ray emission. Direct detection of these photons by instruments on balloons and satellites provides unique information on the stellar production sites, which cannot be obtained through observations at other wavelengths. Because the lifetimes of Al26 and Fe60 are long enough to allow sufficient amounts of these isotopes to accumulate in the Milky Way and give rise to a detectable signal, these two isotopes have long been prime candidates for gamma-ray astronomy. During this talk we will discuss the colorful history, the exciting present state, and the bright future of our attempts to understand the nuclear astrophysics of these two radioactive isotopes.