English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The astrophysical $^{3}{\rm He}(\alpha, \gamma)^{7}{\rm Be}$ and $^{3}{\rmH}(\alpha, \gamma)^{7}{\rm Li}$ direct capture processes are studied in theframework of the two-body model with the potentials of a simple Gaussian form,which describe correctly the phase-shifts in the s-, p-, d-, and f-waves, aswell as the binding energy and the asymptotic normalization constant of theground $p_{3/2}$ and the first excited $p_{1/2}$ bound states. It is shown thatthe E1-transition from the initial s-wave to the final p-waves is stronglydominant in both capture reactions. On this basis the s-wave potentialparameters are adjusted to reproduce the new data of the LUNA collaborationaround 100 keV and the newest data at the Gamov peak estimated with the help ofthe observed neutrino fluxes from the Sun, $S_{34}$(23$^{+6}_{-5}$keV)=0.548$\pm$0.054 keV b for the astrophysical S-factor of the captureprocess $^{3}{\rm He}(\alpha, \gamma)^{7}{\rm Be}$. The resulting modeldescribes well the astrophysical S-factor in low-energy Big Bangnucleosynthesis region of 180-400 keV, however has a tendency to underestimatethe data above 0.5 MeV. Two-body potentials, adjusted on the properties of the$^7$Be nucleus, $^3{\rm He}+\alpha$ elastic scattering data and theastrophysical S-factor of the $^{3}{\rm He}(\alpha, \gamma)^{7}{\rm Be}$ directcapture reaction, are able to reproduce the properties of the $^7$Li nucleus,the binding energies of the ground 3/2$^-$ and first excited 1/2$^-$ states,and phase shifts of the $^3 {\rm H}+\alpha$ elastic scattering in partialwaves. Most importantly, these potential models can successfully describe bothabsolute value and energy dependence of the existing experimental data for themirror astrophysical $^{3}{\rm H}(\alpha, \gamma)^{7}{\rm Li}$ capture reactionwithout any additional adjustment of the parameters.

physical review. c

Astrophysical $^{3}{\rm He}(\alpha, \gamma)^{7}{\rm Be}$ and $^{3}{\rm  H}(\alpha,\gamma)^{7}{\rm Li}$ direct capture reactions in a potential model  approach