Speaker
Prof.
John D'Auria
(Simon Fraser University)
Description
As pointed out by Willie Fowler, the goals of nuclear astrophysics are to understand
the mechanism of Nucleosynthesis and the process of energy generation in stellar
environments. While a good deal is now known on what occurs in quiescent stellar
burning, much less is known about pathways to heavy element production in explosive
scenario. The former is largely dominated by nuclear reactions involving stable
nuclei over long time scales, but the latter occur on much shorter time scale
(seconds) and involve radioactive nuclei. With recent technological breakthroughs,
it is now possible to measure rates of key nuclear reactions involving short-lived
reactants in novae, X-ray bursts and type I supernovae. Such sub-coulomb barrier
reactions exhibit very low cross sections, usually involve hydrogen, and are
difficult to measure at temperatures in stellar environments. This talk will review
how these challenges have been met around the world with the production of intense
radioactive beams of low velocities to provide both direct and indirect measurements
of the key parameters, namely level resonance strengths. A number of laboratories
are now capable of measuring rates of reactions involving radioactive reactants and
helping to clarify the mechanism of explosive stellar phenomena. ISOLDE is the
benchmark world facility for producing intense beams of radioactive nuclei and can
play an important role in such studies; a role that could be unique in the world.
Examples of such studies around the world will be presented and discussed in the
context of the future of ISOLDE.
Primary author
Prof.
John D'Auria
(Simon Fraser University)
