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C. Massimi, E. Griesmayer, E. Jericha, H. Leeb, C. Weiß, -. n_TOF Collaboration et al.:
"Neutron spectroscopy of ²⁶Mg states: Constraining the stellar neutron source ²²Ne(α,n)²⁵Mg";
Physics Letters B, 768 (2017), 1 - 6.

This work reports on accurate, high-resolution measurements of the ²⁵Mg(n,γ)²⁶Mg and ²⁵Mg(n,tot) cross sections in the neutron energy range from thermal to about 300 keV, leading to a significantly improved ²⁵Mg(n,γ)²⁶Mg parametrization. The relevant resonances for n+²⁵Mg were characterized from a combined R-matrix analysis of the experimental data. This resulted in an unambiguous spin/parity assignment of the corresponding excited states in ²⁶Mg. With this information experimental upper limits of the reaction rates for ²²Ne(α,n)²⁵Mg and ²²Ne(α,γ)²⁶Mg were established, potentially leading to a significantly higher (α,n)/(α,γ) ratio than previously evaluated. The impact of these results has been studied for stellar models in the mass range 2 to 25 M_⊙

s Process; α+²²Ne; Neutron spectroscopy

http://dx.doi.org/10.1016/j.physletb.2017.02.025