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In this Letter we report on the first inverse kinematics measurement of key resonances in the 22Ne(p, γ )23Na reaction which forms part of the NeNa cycle, and is relevant for 23Na synthesis in asymptotic giant branch (AGB) stars. An anti-correlation in O and Na abundances is seen across all well-studied globular clusters (GC), however, reaction-rate uncertainties limit the precision as to which stellar evolution models can reproduce the observed isotopic abundance patterns. Given the importance of GC observations in testing stellar evolution models and their dependence on NeNa reaction rates, it is critical that the nuclear physics uncertainties on the origin of 23Na be addressed. We present results of direct strengths measurements of four key resonances in 22Ne(p, γ )23Na at Ec.m. = 149 keV, 181 keV, 248 keV and 458 keV. The strength of the important Ec.m. = 458 keV reference resonance has been determined independently of other resonance strengths for the first time with an associated strength of ωγ = 0.439(22) eV and with higher precision than previously reported. Our result deviates from the two most recently published results obtained from normal kinematics measurements performed by the LENA and LUNA collaborations but is in agreement with earlier measurements. The impact of our rate on the Na-pocket formation in AGB stars and its relation to the O-Na anti-correlation was assessed via network calculations. Further, the effect on isotopic abundances in CO and ONe novae ejecta with respect to pre-solar grains was investigated ; The authors thank the ISAC operations and technical staff at TRIUMF. TRIUMF's core operations are supported via a contribution from the federal government through the National Research Council Canada, and the Government of British Columbia provides building capital funds. DRAGON is supported by funds from the National Sciences and Engineering Research Council of Canada SAPPJ-2019-00039. The authors acknowledge support from the "ChETEC" COST Action (CA16117), supported by COST 116 (European Cooperation in Science and Technology). MW, AML, JR were supported by the UK Science and Technology Facilities Council (STFC) ST/P003885/1. UB acknowledges support from the European Research Council ERC-2015-STG Nr. 677497. J. José acknowledges support from the Spanish MINECO grant AYA2017-86274-P, the EU FEDER funds and the AGAUR/Generalitat de Catalunya grant SGR-661/2017. Authors from the Colorado School of Mines acknowledge funding via the U.S. Department of Energy grant DE-FG02-93ER40789. ; Peer reviewed

[Background]: Globular clusters are known to exhibit anomalous abundance trends such as the sodium-oxygen anticorrelation. This trend is thought to arise via pollution of the cluster interstellar medium from a previous generation of stars. Intermediate-mass asymptotic giant branch stars undergoing hot bottom burning (HBB) are a prime candidate for producing sodium-rich oxygen-poor material, and then expelling this material via strong stellar winds. The amount of 23Na produced in this environment has been shown to be sensitive to uncertainties in the 22Ne(p,γ)23Na reaction rate. The 22Ne(p,γ)23Na reaction is also activated in classical nova nucleosynthesis, strongly influencing predicted isotopic abundance ratios in the Na-Al region. Therefore, improved nuclear physics uncertainties for this reaction rate are of critical importance for the identification and classification of pre-solar grains produced by classical novae. ; [Purpose]: At temperatures relevant for both HBB in AGB stars and classical nova nucleosynthesis, the 22Ne(p,γ)23Na reaction rate is dominated by narrow resonances, with additional contribution from direct capture. This study presents new strength values for seven resonances, as well as a study of direct capture. ; [Method]: The experiment was performed in inverse kinematics by impinging an intense isotopically pure beam of 22Ne onto a windowless H2 gas target. The 23Na recoils and prompt γ rays were detected in coincidence using a recoil mass separator coupled to a 4π bismuth-germanate scintillator array surrounding the target. ; [Results]: For the low-energy resonances, located at center of mass energies of 149, 181, and 248 keV, we recover stength values of ωγ149=0.17+0.05−0.04, ωγ181=2.2±0.4, and ωγ248=8.2±0.7 μeV, respectively. These results are in broad agreement with recent studies performed by the LUNA and TUNL groups. However, for the important reference resonance at 458 keV we obtain a strength value of ωγ458=0.44±0.02 eV, which is significantly lower than recently reported values. This is the first time that this resonance has been studied completely independently from other resonance strengths. For the 632-keV resonance we recover a strength value of ωγ632=0.48±0.02 eV, which is an order of magnitude higher than a recent study. For reference resonances at 610- and 1222-keV, our strength values are in agreement with the literature. In the case of direct capture, we recover an S factor of 60 keV b, consistent with prior forward kinematics experiments. ; [Conclusions]: In summary, we have performed the first direct measurement of 22Ne(p,γ)23Na in inverse kinematics. Our results are in broad agreement with the literature, with the notable exception of the 458-keV resonance, for which we obtain a lower strength value. We assessed the impact of the present reaction rate in reference to a variety of astrophysical environments, including AGB stars and classical novae. Production of 23Na in AGB stars is minimally influenced by the factor of 4 increase in the present rate compared to the STARLIB-2013 compilation. The present rate does however impact upon the production of nuclei in the Ne-Al region for classical novae, with dramatically improved uncertainties in the predicted isotopic abundances present in the novae ejecta. ; The authors thank the ISAC operations and technical staff at TRIUMF. TRIUMFs core operations are supported via a contribution from the federal government through the National Research Council Canada, and the Government of British Columbia provides building capital funds. DRAGON is supported by funds from the National Sciences and Engineering Research Council of Canada. UK authors gratefully acknowledge support from the Science and Technology Facilities Council (STFC). J.J. acknowledges support from the Spanish MINECO Grant No. AYA2017-86274-P, the EU FEDER funds and the AGAUR/ Generalitat de Catalunya Grant No. SGR-661/2017. Authors from the Colorado School of Mines acknowledge funding via U.S. Department of Energy Grant No. DE-FG02-93ER40789. U.B. acknowledges support from the European Research Council (Grant No. ERC-2015-STG Nr. 677497). This article also benefited from discussions within the ChETEC COST Action (Grant No. CA16117). ; Peer reviewed