The thermonuclear rate of the 50Fe（p, γ）51Co reaction in the Type I X-ray bursts （XRBs） temperature range has been reevaluated based on a recent precise mass measurement at CSRe Lanzhou, where the proton separa-...The thermonuclear rate of the 50Fe（p, γ）51Co reaction in the Type I X-ray bursts （XRBs） temperature range has been reevaluated based on a recent precise mass measurement at CSRe Lanzhou, where the proton separa- tion energy Sp=142±77 keV has been determined firstly for the ~1Co nucleus. Comparing to the previous theoretical predictions, the experimental Sp value has much smaller uncertainty. Based on the nuclear shell model and mirror nuclear structure information, we have calculated two sets of thermonuclear rates for the 50Fe（p, γ）51Coreaction by utilizing the experimental Sp value. It shows that the statistical-model calculations are not ideally applicable for this reaction primarily because of the low density of low-lying excited states in 51Co. In this work, we recommend that a set of new reaction rates based on the mirror structure of 51Cr should be incorporated in future astrophysical network calculations.展开更多
The proton separation energy Sp of -786.07±11.49 keV has been evaluated for 69Br from a least squares fit of mass difference of analog states versus α/A1/3, where a is the average charge of the mirror nuclei and...The proton separation energy Sp of -786.07±11.49 keV has been evaluated for 69Br from a least squares fit of mass difference of analog states versus α/A1/3, where a is the average charge of the mirror nuclei and A is the mass number. The extracted Sp value is indicative of the rapid proton-capture process rp, and subsequent Type I X-ray bursts.展开更多
基金Supported by Natural Science Foundation of Inner Mongolia Autonomous Region of China(2013MS0916)National Natural Science Foundation of China(11490562,11405228)
文摘The thermonuclear rate of the 50Fe（p, γ）51Co reaction in the Type I X-ray bursts （XRBs） temperature range has been reevaluated based on a recent precise mass measurement at CSRe Lanzhou, where the proton separa- tion energy Sp=142±77 keV has been determined firstly for the ~1Co nucleus. Comparing to the previous theoretical predictions, the experimental Sp value has much smaller uncertainty. Based on the nuclear shell model and mirror nuclear structure information, we have calculated two sets of thermonuclear rates for the 50Fe（p, γ）51Coreaction by utilizing the experimental Sp value. It shows that the statistical-model calculations are not ideally applicable for this reaction primarily because of the low density of low-lying excited states in 51Co. In this work, we recommend that a set of new reaction rates based on the mirror structure of 51Cr should be incorporated in future astrophysical network calculations.
文摘The proton separation energy Sp of -786.07±11.49 keV has been evaluated for 69Br from a least squares fit of mass difference of analog states versus α/A1/3, where a is the average charge of the mirror nuclei and A is the mass number. The extracted Sp value is indicative of the rapid proton-capture process rp, and subsequent Type I X-ray bursts.
