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Studies have shown that alpha-induced nuclear reactions in the hot CNO cycles and on the waiting points of the rp-process play a principal role in energy production and nucleosynthesis on the surface of mass-accreting white dwarfs and neutron stars. This paper will present recent measurements at Notre Dame on the rate of 15 O( α , γ ) and new experiments for ( α ,p) reactions on the waiting point nuclei of 14 O and 26 Si. Preliminary results and astrophysical implications will be discussed.

Simultaneous measurement of the proton-transfer {sup 18}F(d, n){sup 19}Ne and neutron-transfer {sup 18}F(d, p){sup 19}F reactions were performed with a {sup 18}F radioactive beam at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. The experiments clarify the nuclear structure of {sup 19}Ne near the proton threshold, which is relevant for understanding the rates of proton-induced reactions on {sup 18}F in novae. Analogs for several states in the mirror nucleus {sup 19}F have not yet been identified in {sup 19}Ne, indicating that the level structure of {sup 19}Ne in this region is incomplete. We observed 15 levels in {sup 19}Ne from the {sup 18}F(d, n){sup 19}Ne measurement and 18 levels in {sup 19}F from the {sup 18}F(d, p){sup 19}F measurement. Angular distributions were extracted for all strongly populated states and compared to distorted-wave Born approximation calculations. The angular distributions for all the known states in the two nuclei determined in this work are consistent with their previously assigned spins and parities. The spectroscopic factors determined for these levels in the two nuclei are reported.

The ${}^{18}\mathrm{F}(p,\ensuremath{\alpha}){}^{15}\mathrm{O}$ reaction is the predominant destruction mechanism in novae of the radionuclide $^{18}\mathrm{F}$, a target of $\ensuremath{\gamma}$-ray observatories. Thus, its rate is important for understanding $^{18}\mathrm{F}$ production in novae. We have studied resonances in the ${}^{18}\mathrm{F}+p$ system by making a measurement of a proton-transfer reaction ${}^{18}\mathrm{F}(d,n)$. We have observed 15 $^{19}\mathrm{Ne}$ levels, 5 of which are below the proton threshold, including a subthreshold state, which has significant ${l}_{p}=0$ strength. Our data provide a direct determination of the spectroscopic strength of these states and new constraints on their spins and parities, thereby resolving a controversy, which involves the 8- and 38-keV resonances. The ${}^{18}\mathrm{F}(p,\ensuremath{\alpha}){}^{15}\mathrm{O}$ reaction rate is reevaluated, which takes the subthreshold resonance and other new information determined in this experiment into account.

The reactions of {sup 6}Li on {sup 58}Fe and {sup 7}Li on {sup 57}Fe have been studied at 15 MeV beam energy. These two reactions produce the same compound nucleus, {sup 64}Cu. The charged particle spectra were measured at backward angles. The data obtained have been compared with Hauser-Feshbach model calculations. The level density parameters of {sup 63}Ni and {sup 60}Co have been obtained from the particle evaporation spectra. We also find contributions from the break up of the lithium projectiles to the low energy region of the {alpha} spectra.

The reactions of 6Li on 58Fe and 7Li on 57Fe have been studied at beam energy 15 MeV. These two reactions produce the same compound nucleus, 64Cu. The neutron, proton, and alpha spectra were measured at backward angles. The data obtained have been compared with Hauser Fesh‐bach model calculations. The level density parameters of the residual nuclei have been obtained from the particle evaporation spectra.