标题： 15O中6792 keV态的寿命测量，对于14N(p,γ)15O天体物理S因子外推很重要 显示英文标题

标题： Lifetime measurement of the 6792 keV state in 15O, important for the astrophysical S factor extrapolation in 14N(p,g)15O

摘要： 我们报告通过在反应14N(p,γ)15O的E=259 keV共振处的多普勒位移衰减法对15O中E_x=6792 keV状态的新寿命测量。这个亚阈值状态对于在恒星能量下确定14N(p,γ)15O基态天体物理S因子具有特别重要的意义。与之前的工作相比，测量技术得到了显著改进。之前得出的有限寿命结论无法用目前的数据确认。此外，为了验证实验方法，使用相同的技术测量了E_x=5181和6172 keV两个状态的寿命。我们观察到E_x=6172和6792 keV状态的衰减因子F(tau)>0.98，分别对应tau<0.77 fs。E_x=5181 keV状态的衰减因子结果为F(tau)=0.78+/-0.02，对应tau=8.4+/-1.0 fs，与文献结果非常一致。 显示英文摘要

摘要： We report on a new lifetime measurement of the E_x=6792 keV state in 15O via the Doppler-shift attenuation method at the E=259 keV resonance in the reaction 14N(p,g)15O. This subthreshold state is of particular importance for the determination of the ground state astrophysical S factor of 14N(p,g)15O at stellar energies. The measurement technique has been significantly improved compared with previous work. The conclusion of a finite lifetime drawn there cannot be confirmed with the present data. In addition, the lifetime of the two states at E_x=5181 and 6172 keV have been measured with the same technique in order to verify the experimental method. We observe an attenuation factor F(tau)>0.98 for the E_x =6172 and 6792 keV states, respectively, corresponding to tau<0.77 fs. The attenuation factor for the E_x=5181 keV state results in F(tau)=0.78+/-0.02 corresponding to tau=8.4+/-1.0 fs in excellent agreement with literature.