Measurement of the 183 keV resonance in 17O(p,α)14N using a novel technique

We have developed a novel technique for measurements of low-energy (p,alpha) reactions using heavy-ion beams and a differentially pumped windowless gas target. We applied this new approach to study the 183 keV resonance in the O-17(p,alpha)N-14 reaction. We report a (center-of-mass) resonance energy of E-r=183.5(-0.4)(+0.1) keV and a resonance strength of omega gamma(p alpha) = (1.70 +/- 0.15) meV, and we set an upper limit (95% confidence) on the total width of the state of Gamma < 0.1 keV. This resonance is important for the O-17(p,alpha)N-14 reaction rate, and we find that F-18 production is significantly decreased in low-mass ONeMg novae but less affected in more energetic novae. We also report the first determination of the stopping power for oxygen ions in hydrogen gas near the peak of the Bragg curve (E = 193 keV/u) to be (63 +/- 1) x 10(-15) eV cm(2).