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An accreting compact star in a binary system can generate periodic thermonuclear runaways on its surface. In the case of a white dwarf star, the result is a classical nova, which enriches the interstellar medium with newly synthesized nuclides. In the case of a neutron star, a detectable burst of X-rays is emitted. Nucleosynthesis and energy generation in these events depends on resonant thermonuclear reaction rates, which are especially challenging to measure directly in the laboratory when they involve radioactive reactants. Fortunately, the resonances can be discovered and their relevant properties can be constructed using nuclear structure experiments. We will describe a program of beta decay experiments the National Superconducting Cyclotron Laboratory to this end. In particular, the Gaseous Detector with Germanium Tagging (GADGET) system, developed to measure very weak low-energy beta delayed proton emission branches and gamma rays, is now operational. Recent results and future opportunities at the Facility for Rare Isotope Beams will be discussed.

The two rp-reactions 34S(p,γ)35Cl and 34 g,m Cl(p,γ)35Ar were studied via a shell-model approach. At energies in the resonance region near the proton-emission threshold many negative-parity states appear. We present results of calculations in a full (0+1)ℏω model space which addresses this problem. Energies, spectroscopic factors and proton-decay widths are calculated for input into the reaction rates. Comparisons are also made with a recent experimental determination of the reaction rate for the 34S(3He,d)35Cl reaction. The thermonuclear 34 g,m Cl(p,γ)35Ar reaction rates are unknown because of a lack of experimental data. The rates for transitions from the ground state of 34Cl as well as from the isomeric first excited state of 34Cl are explicitly calculated taking into account the relative populations of the two states.

A small fraction (< 1%) of presolar SiC grains is suggested to have been formed in the ejecta of classical novae. The 29P(p,γ)30S reaction plays an important role in understanding the Si isotopic abundances in such grains, which in turn provide us with information on the nature of the probable white dwarf progenitor's core, as well as the peak temperatures achieved during nova outbursts, and thus the nova nucleosynthetic path. This rate at nova temperatures is determined by two low-lying 3+ and 2+ resonances above the proton threshold at 4399 keV in 30S. Despite several experimental studies in the past, however, these two states have only been observed very recently. We have studied the 30S nuclear structure via the 32S(p,t)30S reaction at 5 laboratory angles between 9° to 62°. We have observed 14 states, eleven of which are above the proton threshold, including two levels at 4692.7 ± 4.5 keV and 4813.8 ± 3.4 keV that are candidates for the 3+ and the previously "missing" 2+ state, respectively.