Measurement of the cross section for the reaction 20Ne(n,α)17O in the neutron-energy between 4 and 7 MeV

Abstract

The cross section for the reaction 20 Ne(n, α) 17 O was measured in the neutron-energy range 4-7 MeV. An ionization chamber equipped with a Frisch grid combined with a pulse-shape digitizer was used as a detector. Gaseous neon that served as a target on which the reaction being studied proceeded was added to the gas filling the ionization chamber. The partial cross sections for the α 0 , α 1 , α 2 , and α 3 channels of the reaction 20 Ne(n, α) 17 O were obtained for the first time.

Uncertainty of the astrophysical O17,18(α,n)Ne20,21Mohr1 2017Phys. Rev. C9070View full textAdd to dashboardCite

“…For the 18 O(α,n) 21 Ne reaction good agreement between all experimental data is found, leading to an experimentally well-constrained reaction rate N A σv . Surprisingly, for the 17 O(α,n) 20 Ne reaction a significant discrepancy has been found at energies above the (α,n 1 ) threshold between the data by Best et al [23] and several other (α,n) [19][20][21][22]24] and (n,α) [25][26][27][28] data sets. This experimental discrepancy has to be resolved for a better definition of the 17 O(α,n) 20 Ne rate at higher temperatures above T 9 ≈ 1.…”

“…Bell et al [26] are able to resolve the α 0 and α 1 channels for low neutron energies between 3 and 4.5 MeV; at higher energies also only the sum of the first two channels is reported. At energies above 4 MeV, recently Khryachkhov et al [27,28] have also measured the sum of the α 0 and α 1 channels. The (n,α) data are in good agreement below 5 MeV (see Fig.…”

“…A significant discrepancy can be seen between the Best data and the data from the reverse (n,α) reaction. For completeness also (Color online) Experimental cross section of the 20 Ne(n,α) 17 O reaction [25][26][27][28] in comparison to a statistical model calculation. Because of the dominating α0 channel, the (n,α) data provide an additional constraint for the 17 O(α,n0) 20 Ne cross section.…”

“…In the course of this study of 17 F+α, the mirror 17 O(α,n) 20 Ne reaction was also analyzed, and unexpected inconsistencies between different experimental data sets were identified. These are based on the 17 O(α,n) 20 Ne data in [19][20][21][22][23][24] and the reverse 20 Ne(n,α) 17 O reaction [25][26][27][28]. As a consequence, the present work now focuses on the resulting uncertainties of the 17 O(α,n) 20 Ne reaction rate.…”

“…4. (Color online) Experimental cross section of the 20 Ne(n,α)17 O reaction[25][26][27][28] in comparison to a statistical model calculation. Because of the dominating α0 channel, the (n,α) data provide an additional constraint for the 17 O(α,n0)20 Ne cross section.…”