Three new low-energy resonances in the ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction

Abstract

The ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle affects the synthesis of the elements between ${}^{20}$Ne and ${}^{27}$Al in asymptotic giant branch stars and novae. The ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction rate is very uncertain because of a large number of unobserved resonances lying in the Gamow window. At proton energies below 400\,keV, only upper limits exist in the literature for the resonance strengths. Previous reaction rate evaluations differ by large factors. In the present work, the first direct observations of the ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na resonances at 156.2, 189.5, and 259.7\,keV are reported. Their resonance strengths have been derived with 2-7\% uncertainty. In addition, upper limits for three other resonances have been greatly reduced. Data were taken using a windowless ${}^{22}$Ne gas target and high-purity germanium detectors at the Laboratory for Underground Nuclear Astrophysics in the Gran Sasso laboratory of the National Institute for Nuclear Physics, Italy, taking advantage of the ultra-low background observed deep underground. The new reaction rate is a factor of 5 higher than the recent evaluation at temperatures relevant to novae and asymptotic giant branch stars nucleosynthesis.

6 pages, 4 figures, submitted to Phys. Rev. Lett

References in corpus (15)

• Fast rotating massive stars and the origin of the abundance patterns in galactic globular clusters
• Super-Massive Stars as a Source of Abundance Anomalies of Proton-Capture Elements in Globular Clusters
• STARLIB: A Next-Generation Reaction-Rate Library for Nuclear Astrophysics
• Activation measurement of the 3He(alpha,gamma)7Be cross section at low energy
• LUNA: Nuclear Astrophysics Deep Underground
• Reaction rate uncertainties and the operation of the NeNa and MgAl chains during HBB in intermediate-mass AGB stars
• Carbon-rich presolar grains from massive stars. Subsolar 12C/13C and 14N/15N ratios and the mystery of 15N
• The Reduction of the Electron Abundance during the Pre-explosion Simmering in White Dwarf Supernovae
• The self-enrichment scenario in intermediate metallicity globular clusters
• First Direct Measurement of the ^{17}O(p,γ)^{18}F Reaction Cross-Section at Gamow Energies for Classical Novae
• A new study of the ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction deep underground: Feasibility, setup, and first observation of the 186 keV resonance
• An actively vetoed Clover gamma-detector for nuclear astrophysics at LUNA
• Direct measurements of 22Na(p,g)23Mg resonances and consequences for 22Na production in classical novae
• Strengths of the resonances at 436, 479, 639, 661, and 1279 keV in the ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction
• Light-Element Abundances of Giant Stars in the Globular Cluster M71 (NGC 6838)

Cited by in corpus (27)

• Heavy-element yields and abundances of Asymptotic Giant Branch models with a Small Magellanic Cloud metallicity
• LUNA: Status and Prospects
• Improved Direct Measurement of the 64.5 keV Resonance Strength in the 17O(p,a)14N Reaction at LUNA
• Direct measurement of low-energy ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na resonances
• The Relationship Between Globular Cluster Mass, Metallicity, and Light Element Abundance Variations
• A high-efficiency gas target setup for underground experiments, and redetermination of the branching ratio of the 189.5 keV ${}^{22}\mathbf{Ne}(\mathbf{p},\gamma {)}^{23}\mathbf{Na}$ resonance
• ${}^{22}$Ne and ${}^{23}$Na ejecta from intermediate-mass stars: The impact of the new LUNA rate for ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na
• Direct capture cross section and the $E_p$ = 71 and 105 keV resonances in the ${}^{22}$Ne($p,\gamma$)${}^{23}$Na reaction
• Underground nuclear astrophysics: why and how
• Advances in Radiative Capture Studies at LUNA with a Segmented BGO Detector
• Partial mixing and the formation of 13C pockets in AGB stars: effects on the s-process elements
• First direct limit on the 334 keV resonance strength in the ${}^{22}$Ne(α,γ)${}^{26}$Mg reaction
• Background in $\gamma$-ray detectors and carbon beam tests in the Felsenkeller shallow-underground accelerator laboratory
• Exploring Stars in Underground Laboratories: Challenges and Solutions
• Solar fusion III: New data and theory for hydrogen-burning stars
• First inverse kinematics study of the ${}^{22}$Ne$(p,\gamma {)}^{23}$Na reaction and its role in AGB star and classical nova nucleosynthesis
• Sensitivity of ${}^{44}$Ti and ${}^{56}$Ni production in CCSN shock-driven nucleosynthesis to reaction rates
• Shell and explosive hydrogen burning
• Effect of beam energy straggling on resonant yield in thin gas targets: The cases ${}^{22}$Ne(p,γ)${}^{23}$Na and ${}^{14}$N(p,γ)${}^{15}$O
• Underground Measurements of Nuclear Reaction Cross-Sections Relevant to AGB Stars
• First inverse kinematics measurement of key resonances in the ${}^{22}\text{Ne}(p,\gamma {)}^{23}\text{Na}$ reaction at stellar temperatures
• Asymptotic normalization coefficients from transfer reaction and R-martix analysis of direct capture in ${}^{22}$Ne(p,$\gamma$)${}^{23}$Na reaction
• Searching for resonance states in ${}^{22}$Ne($p,\gamma$)${}^{23}$Na
• Detectors and Shieldings: Past and Future at LUNA
• Progress of the Felsenkeller shallow-underground accelerator for nuclear astrophysics
• Underground nuclear astrophysics: Status and recent results from Felsenkeller laboratory
• Urca Nuclide Production in Type-I X-ray Bursts and Implications for Nuclear Physics Studies