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The $^{15}$O($alpha$,$gamma$)$^{19}$Ne Breakout Reaction and Impact on X-Ray Bursts

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 نشر من قبل Wanpeng Tan
 تاريخ النشر 2007
  مجال البحث فيزياء
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The breakout reaction $^{15}$O($alpha,gamma$)$^{19}$Ne, which regulates the flow between the hot CNO cycle and the rp-process, is critical for the explanation of the burst amplitude and periodicity of X-ray bursters. We report on the first successful measurement of the critical $alpha$-decay branching ratios of relevant states in $^{19}$Ne populated via $^{19}$F($^3$He,t)$^{19}$Ne. Based on the experimental results and our previous lifetime measurements of these states, we derive the first experimental rate of $^{15}$O($alpha,gamma$)$^{19}$Ne. The impact of our experimental results on the burst pattern and periodicity for a range of accretion rates is analyzed.



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