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arXiv 0804.19772008-04-12nucl-ex

Comment on "15O(alpha,gamma)19Ne Breakout Reaction and Impact on X-Ray Bursts"

B. Davids

备注：: Submitted to Physical Review Letters; comments and suggestions are welcome

英文摘要：

A recently published letter reports a measurement of alpha decay from states in 19Ne at excitation energies below 4.5 MeV. The measured alpha decay branching ratios B_alpha are used to calculate the astrophysical rate of the 15O(alpha,gamma)19Ne reaction and to draw conclusions regarding the transition between steady state and unstable nuclear burning on accreting neutron stars. Here I show that the calculated astrophysical reaction rate is based on an unreliable value of B_alpha for the 4.03 MeV state and point out a serious internal inconsistency in the letter's treatment of low statistics alpha decay measurements.

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