Measurement of the 183 keV resonance in O17(p,α)N14 using a novel technique

B. H. Moazen, ORNL Physics Division
D. W. Bardayan, ORNL Physics Division
J. C. Blackmon, ORNL Physics Division
K. Y. Chae, ORNL Physics Division
K. Chipps, Colorado School of Mines
C. P. Domizioli, Tennessee Technological University
R. Fitzgerald, The University of North Carolina at Chapel Hill
U. Greife, Colorado School of Mines
W. R. Hix, ORNL Physics Division
K. L. Jones, The University of Tennessee, Knoxville
R. L. Kozub, Tennessee Technological University
E. J. Lingerfelt, ORNL Physics Division
R. J. Livesay, Colorado School of Mines
C. D. Nesaraja, ORNL Physics Division
S. D. Pain, Rutgers University–New Brunswick
L. F. Roberts, ORNL Physics Division
J. F. Shriner, Tennessee Technological University
M. S. Smith, ORNL Physics Division
J. S. Thomas, Rutgers University–New Brunswick


We have developed a novel technique for measurements of low-energy (p,α) 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 O17(p,α)N14 reaction. We report a (center-of-mass) resonance energy of Er=183.5+0.1-0.4 keV and a resonance strength of ωγpα=(1.70±0.15) meV, and we set an upper limit (95% confidence) on the total width of the state of Γ<0.1 keV. This resonance is important for the O17(p,α)N14 reaction rate, and we find that F18 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)×10-15 eV cm2. © 2007 The American Physical Society.