In:
The Astrophysical Journal, American Astronomical Society, Vol. 915, No. 2 ( 2021-07-01), p. 78-
Abstract:
Rare information on photodisintegration reactions of nuclei with mass numbers A ≈ 160 at astrophysical conditions impedes our understanding of the origin of p -nuclei. Experimental determination of the key ( p , γ ) cross sections has been playing an important role in verifying nuclear reaction models and providing rates of relevant ( γ , p ) reactions in the γ process. In this paper we report the first cross-section measurements of 160 Dy( p , γ ) 161 Ho and 161 Dy( p , n ) 161 Ho in the beam energy range of 3.4–7.0 MeV, partially covering the Gamow window. Such determinations are possible by using two targets with various isotopic fractions. The cross-section data can put a strong constraint on the nuclear level densities and gamma strength functions for A ≈ 160 in the Hauser–Feshbach statistical model. Furthermore, we find the best parameters for TALYS that reproduce the available A ∼ 160 data, 160 Dy( p , γ ) 161 Ho and 162 Er( p , γ ) 163 Tm, and recommend the constrained 161 Ho( γ , p ) 160 Dy reaction rates over a wide temperature range for γ process network calculations. Although the determined 161 Ho( γ , p) stellar reaction rates at the temperature of 1 to 2 GK can differ by up to one order of magnitude from the NON-SMOKER predictions, it has a minor effect on the yields of 160 Dy and accordingly the p -nuclei, 156,158 Dy. A sensitivity study confirms that the cross section of 160 Dy( p , γ ) 161 Ho is measured precisely enough to predict yields of p nuclei in the γ process.
Type of Medium:
Online Resource
ISSN:
0004-637X
,
1538-4357
DOI:
10.3847/1538-4357/ac00b1
Language:
Unknown
Publisher:
American Astronomical Society
Publication Date:
2021
detail.hit.zdb_id:
2207648-7
detail.hit.zdb_id:
1473835-1
SSG:
16,12
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