Ms. Smith et al., GAMMA-WIDTH OF O-14-ASTERISK(5.17 MEV) AND THE STELLAR N-13(P, GAMMA)O-14 REACTION-RATE, Physical review. C. Nuclear physics, 47(6), 1993, pp. 2740-2750
We have determined the gamma-ray branching ratio GAMMA(gamma)/GAMMA(to
t) for the first excited state in O-14 (E(x) = 5.17 MeV) to be (3.1 +/
- 1.7) X 10(-4), corresponding to a gamma width of 12 +/- 7 eV. This v
alue was determined by measuring the ratio of the N-14(p, n)O-14(0) to
N-14(p, n)O-14(1) cross sections via neutron time of flight, and the
ratio of N-14(p, n)O-14(0) to N-14(p, n)O-14(1)(gamma)O-14(0) cross se
ctions at the same center-of-mass energy by bombarding a hydrogen targ
et with a N-14 beam and kinematically distinguishing the O-14(0) recoi
ls from the two reaction channels. The present value for GAMMA(gamma)
is consistent with other measurements at the 2-sigma level; a weighted
mean of all measurements is used to calculate the stellar N-13(p, gam
ma)O-14 reaction rate, and thereby determine the temperatures and dens
ities at which the stellar carbon-nitrogen-oxygen (CNO) cycle is conve
rted to the hot CNO cycle.