A HIGH-RESOLUTION STUDY OF THE NE-20(HE-3, T)NA-20 REACTION AND THE NE-19(P,GAMMA)NA-20 REACTION-RATE

A high-precision measurement of the Ne-20(He-3, t)Na-20 reaction has been made using implanted Ne-20 transmission targets to obtain pertinent information on the low-energy resonances in the Ne-19(p, gamma)Na-20 reaction. Resonance energies (447 +/- 5, 658 +/- 5, 787 +/- 5, and 857 +/- 5 keV) and upper limits on total intrinsic widths (< 10, < 6, < 10, and < 16 keV) have been measured for four excited states above the 2.199 MeV proton threshold in Na-20. The stellar Ne-19(p, gamma)Na-20 reaction rate is calculated for temperatures between 1 x 10(8) and 1 x 10(9) K. When combined with a recent study of the O-15(alpha, gamma)Ne-19 reaction, a new estimate is made of the conditions required for breakout from the Hot CNO cycle to the rapid proton capture process.