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1. ²⁰ Ne(α,p) ²³ Na studied to constrain type Ia nucleosynthesis

   https://doi.org/10.1088/1742-6596/2586/1/012110  

   Boomershine, C N; Bardayan, D W; Carmichael, S; Caves, L; Davis, A; deBoer, R J; Gula, A; Howard, K; Kelmar, R; Mitchell, A; et al (September 2023, Journal of Physics: Conference Series)

   Abstract The²⁰Ne(α,p)²³Na reaction rate is important in determining the final abundances of various nuclei produced in type Ia supernovae. Previously, the ground state cross section was calculated from time reversal reaction experiments using detailed balance. The reaction rates extracted from these studies do not consider contributions from the population of excited states, and therefore, are only estimates. A resonance scan, populating both the ground and first excited states, was performed for the²⁰Ne(α,p)²³Na reaction, measuring between 2.9 and 5 MeV center of mass energies at the Nuclear Science Lab at the University of Notre Dame. Data analysis is underway and preliminary results show substantial contribution from the excited state reaction. 

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2. Global R-matrix analysis of the ¹¹ B(α,n) ¹⁴ N reaction

   https://doi.org/10.1088/1742-6596/1668/1/012011  

   deBoer, R. J.; Liu, Q.; Chen, Y.; Couder, M.; Görres, J.; Lamere, E.; Long, A.M.; Lyons, S.; Manukyan, K.; Morales, L.; et al (October 2020, Journal of Physics: Conference Series)

   null (Ed.)
3. Effective field theory analysis of ³ He–α scattering data

   https://doi.org/10.1088/1361-6471/ac4da6  

   Poudel, Maheshwor; Phillips, Daniel R (March 2022, Journal of Physics G: Nuclear and Particle Physics)

   Abstract We treat low-energy 3 He– α elastic scattering in an effective field theory (EFT) that exploits the separation of scales in this reaction. We compute the amplitude up to next-to-next-to-leading order, developing a hierarchy of the effective-range parameters (ERPs) that contribute at various orders. We use the resulting formalism to analyse data for recent measurements at center-of-mass energies of 0.38–3.12 MeV using the scattering of nuclei in inverse kinematics (SONIK) gas target at TRIUMF as well as older data in this energy regime. We employ a likelihood function that incorporates the theoretical uncertainty due to truncation of the EFT and use Markov chain Monte Carlo sampling to obtain the resulting posterior probability distribution. We find that the inclusion of a small amount of data on the analysing power A y is crucial to determine the sign of the p-wave splitting in such an analysis. The combination of A y and SONIK data constrains all ERPs up to O ( p 4 ) in both s- and p-waves quite well. The asymptotic normalisation coefficients and s-wave scattering length are consistent with a recent EFT analysis of the capture reaction 3 He( α , γ ) 7 Be. 

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4. Shades: ²² Ne( α , n) ²⁵ Mg reaction rate in the Gamow window

   https://doi.org/10.1051/epjconf/202226011031  

   Rapagnani, David; Ananna, Chemseddine; Di Leva, Antonino; Imbriani, Gianluca; Junker, Matthias; Pignatari, Marco; Best, Andreas (January 2022, EPJ Web of Conferences)

   Liu, W.; Wang, Y.; Guo, B.; Tang, X.; Zeng, S. (Ed.)

   Neutron capture reactions are the main contributors to the synthesis of the heavy elements through the s-process. Together with 13 C( α , n) 16 O, which has recently been measured by the LUNA collaboration in an energy region inside the Gamow peak, 22 Ne( α , n) 25 Mg is the other main neutron source in stars. Its cross section is mostly unknown in the relevant stellar energy (450 keV < E cm < 750 keV), where only upper limits from direct experiments and highly uncertain estimates from indirect sources exist. The ERC project SHADES (UniNa/INFN) aims to provide for the first time direct cross section data in this region and to reduce the uncertainties of higher energy resonance parameters. High sensitivity measurements will be performed with the new LUNA-MV accelerator at the INFN-LNGS laboratory in Italy: the energy sensitivity of the SHADES hybrid neutron detector, together with the low background environment of the LNGS and the high beam current of the new accelerator promises to improve the sensitivity by over 2 orders of magnitude over the state of the art, allowing to finally probe the unexplored low-energy cross section. Here we present an overview of the project and first results on the setup characterization. 

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5. Study of the ⁴⁴ Ti(α, p) ⁴⁷ V reaction rate using high-precision ⁵⁰ Cr(p, t) ⁴⁸ Cr measurements

   https://doi.org/10.1088/1742-6596/2586/1/012106  

   Binda, S D; Adsley, P; Long, A M; Berg, G; Brümmer, J W; Couder, M; Görres, J; Kamimota, M; Khumalo, N; Köhne, M; et al (September 2023, Journal of Physics: Conference Series)

   Abstract The abundance and distribution of⁴⁴Ti tells us about the nature of the core-collapse supernovae explosions. There is a need to understand the nuclear reaction network creating and destroying⁴⁴Ti in order to use it as a probe for the explosive mechanism. The⁴⁴Ti(α, p)⁴⁷V reaction is a very important reaction and it controls the destruction of⁴⁴Ti. Difficulties with direct measurements have led to an attempt to study this reaction indirectly. Here, the first step of the indirect study which is the identification of levels of the compound nucleus⁴⁸Cr is presented. A 100-MeV proton beam was incident on a⁵⁰Cr target. States in⁴⁸Cr were populated in the⁵⁰Cr(p, t)⁴⁸Cr reaction. The tritons were momentum-analysed in the K600 Q2D magnetic spectrometer at iThemba LABS. 

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