出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Explosive hydrogen burning is expected to occur in classical novae and type I x-ray bursts at temperatures up to 2 GK. Energy generation and nucleosynthesis in these events depend on the thermonuclear rates of radiative proton capture reactions involving unstable reactants. For exam- ple, the 19Ne(p;g )20Na, 23Mg(p;g )24Al, 27Si(p;g )28P, 31S(p;g )32Cl, and 35Ar(p;g )36K reaction rates are each expected to be dominated by one or two narrow, isolated resonances whose prop- erties must be determined experimentally. First and foremost, the resonance energies must be known in order to approximate their contributions to the reaction rate and facilitate direct mea- surements with radioactive ion beams. By preparing thin ion implanted carbon foil targets at the University of Washington and measuring the 20Ne(3He,t)20Na, 24Mg(3He,t)24Al, 28Si(3He,t)28P, 32S(3He,t)32Cl, and 36Ar(3He,t)36K reactions on them at 32 MeV with the Munich Q3D spec- trograph, we have measured the ground state masses of 20Na, 24Al, 28P, and 32Cl and excitation energies in 32Cl and 36K to precisions on the order of 1 keV.We discuss our improvements on the thermonuclear rates of the 23Mg(p;g )24Al and 35Ar(p;g )36K reactions.
