Study of (${}^6$Li, $d$) and (${}^6$Li, $t$) reactions on ${}^{22}$Ne and implications for $s$-process nucleosynthesis

Abstract

We studied $\alpha$ cluster states in ${}^{26}$Mg via the ${}^{22}$Ne(${}^6$Li,$d\gamma$)${}^{26}$Mg reaction in inverse kinematics at an energy of $7$ MeV/nucleon. States between $E_x$ = 4 - 12 MeV in ${}^{26}$Mg were populated and relative $\alpha$ spectroscopic factors were determined. Some of these states correspond to resonances in the Gamow window of the ${}^{22}$Ne($\alpha$,n)${}^{25}$Mg reaction, which is one of the main neutron sources in the astrophysical $s$-process. We show that $\alpha$-cluster strength of the states analyzed in this work have critical impact on s-process abundances. Using our new ${}^{22}$Ne($\alpha$,n)${}^{25}$Mg and ${}^{22}$Ne($\alpha$,$\gamma$)${}^{26}$Mg reaction rates, we performed new s-process calculations for massive stars and Asymptotic Giant Branch stars and compared the resulting yields with the yields obtained using other ${}^{22}$Ne+$\alpha$ rates from the literature. We observe an impact on the s-process abundances up to a factor of three for intermediate-mass AGB stars and up to a factor of ten for massive stars. Additionally, states in ${}^{25}$Mg at $E_x$ $<$ 5 MeV are identified via the ${}^{22}$Ne(${}^6$Li,$t$)${}^{25}$Mg reaction for the first time. We present the (${}^6$Li, $t$) spectroscopic factors of these states and note similarities to the $(d,p$) reaction in terms of reaction selectivity.

References in corpus (16)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Multi-messenger Observations of a Binary Neutron Star Merger
• The r-process of stellar nucleosynthesis: Astrophysics and nuclear physics achievements and mysteries
• Light Curves of the Neutron Star Merger GW170817/SSS17a: Implications for R-Process Nucleosynthesis
• The Dawes Review 2: Nucleosynthesis and stellar yields of low and intermediate-mass single stars
• Production of Light Element Primary Process nuclei in neutrino-driven winds
• Integrated Nucleosynthesis in Neutrino Driven Winds
• Chemical evolution with rotating massive star yields II. A new assessment of the solar s- and r- process components
• s-Process Nucleosynthesis in Advanced Burning Phases of Massive Stars
• i-process nucleosynthesis and mass retention efficiency in He-shell flash evolution of rapidly accreting white dwarfs
• Neutron spectroscopy of ${}^{26}$Mg states: constraining the stellar neutron source ${}^{22}$Ne($\alpha ,n$)${}^{25}$Mg
• Experimental evidence of a natural parity state in ${}^{26}$Mg and its impact to the production of neutrons for the s process
• ${}^{60}$Fe in core-collapse supernovae and prospects for X-ray and $\gamma$-ray detection in supernova remnants
• Constraining the ${}^{22}$Ne($\alpha$,$\gamma$)${}^{26}$Mg and ${}^{22}$Ne($\alpha$,n)${}^{25}$Mg reaction rates using sub-Coulomb $\alpha$-transfer reactions
• Decay properties of ${}^{22}\mathrm{Ne}+\alpha$ resonances and their impact on $s$-process nucleosynthesis
• Heavy Elements Nucleosynthesis On Accreting White Dwarfs: building seeds for the p-process

Cited by in corpus (8)

• The s Process and Beyond
• The ${}^{22}$Ne($\alpha$,n)${}^{25}$Mg reaction -- state of the art, astrophysics, and perspectives
• Isotopic ratios for C, N, Si, Al, and Ti in C-rich presolar grains from massive stars
• The s process in massive stars, a benchmark for neutron capture reaction rates
• Strength measurement of the $E_{\alpha }^{lab}$ = 830 keV resonance in ${}^{22}\mathrm{Ne}(\alpha ,\mathrm{n}{)}^{25}\mathrm{Mg}$ reaction using a stilbene detector
• Impact of newly measured 26Al(n, p)26Mg and 26Al(n, α)23Na reaction rates on the nucleosynthesis of 26Al in stars
• Impact of the latest 22Ne+α reaction rates on nucleosynthesis in massive stars and galactic chemical evolution
• Trans-Fe elements from Type Ia Supernovae. I. Heavy element nucleosynthesis during the formation of near-Chandrasekhar white dwarfs