Structure of ^{30}S with ^{32}S(p,t)^{30}S and the thermonuclear ^{29}P(p,γ)^{30}S reaction rate

The structure of proton unbound S-30 states is important for determining the P-29(p,gamma)S-30 reaction rate, which influences explosive hydrogen burning in classical novae and type I x-ray bursts. The reaction rate in this temperature regime had been previously predicted to be dominated by two low-lying, unobserved, J(pi) = 3(+) and 2(+) resonances above the proton threshold in S-30. To search for these levels, the structure of S-30 was studied using the S-32(p, t)S-30 transfer reaction with a magnetic spectrograph. We have confirmed a previous detection of a state near 4700 keV, which had tentatively been assigned J(pi) = 3(+). We have also discovered a new state at 4814(3) keV, which is a strong candidate for the other important resonance (J(pi) = 2(broken vertical bar)). The new P-29(p,gamma)S-30 reaction rate is up to 4-20 times larger than previously determined rates over the relevant temperature range. The uncertainty in the reaction rate due to uncertainties in the resonance energies has been significantly reduced.