Radiative capture of nucleons at astrophysical energies with single-particle states

Abstract

a b s t r a c tRadiative capture of nucleons at energies of astrophysical interest is one of the most important processes for nucleosynthesis. The nucleon capture can occur either by a compound nucleus reaction or by a direct process. The compound reaction cross sections are usually very small, especially for light nuclei. The direct capture proceeds either via the formation of a single-particle resonance or a non-resonant capture process. In this work we calculate radiative capture cross sections and astrophysical S-factors for nuclei in the mass region A < 20 using single-particle states. We carefully discuss the parameter fitting procedure adopted in the simplified two-body treatment of the capture process. Then we produce a detailed list of cases for which the model works well. Useful quantities, such as spectroscopic factors and asymptotic normalization coefficients, are obtained and compared to published data.

Universal properties of infrared oscillator basis extrapolations

“…(42) to the triton assuming a break-up into deuteron plus neutron yields a binding momentum k ∞ ≈ 91 MeV (k expt ∞ = 88.13 MeV) and ANC γ ∞ ≈ 3 fm −1/2 . The ANC is not in agreement with data and previous computations where γ ∞ ≈ 2 fm −1/2 was reported [30,31], and suggests that a more sophisticated analysis is necessary for the three-body problem (see also Refs. [32][33][34]).…”

Study of the nucleon radiative captures 8Li(n,γ)9Li, 9Be(p,γ)10B, 10Be(n,γ)11Be, 10B(p,γ)11C, and 16O(p,γ)17F at thermal and astrophysical energies

“…Now we will note that for the ANC of the GS of 9 Li in Ref. 95 at the spectroscopic factor of S = 0.8 the value A NC = 1.12 fm -1/2 was obtained, i.e., C = 1.25 fm -1/2 , which differs slightly from the average value of the ANC given above. Meanwhile, for the FES of 9 (7) fm -1/2 , which, by and large, agree with all previous values.…”

AstrophysicalS-factor for6Li(ρ, γ)7Be in the coupled-channel Gamow shell model

“…The solid line represents the exact, fully antisymmetrized GSM-CC calculation for capture to both the ground state J π = 3/2 − 1 and the first excited state J π = 1/2 − 1 of 7 Be. Calculations by the potential model [16] and the microscopic cluster model [17] are shown with the dashed and dotted lines, respectively.…”

“…to the final bound state J f = 3/2 experimental data [13][14][15] and other theoretical studies [16,17]. Switkowski et al [13] measured 6 Li(p, γ) 7 Be cross section over a wide energy range of astrophysical interest.…”