Gy. Gyürky, Z. Halász, G.G. Kiss, T. Szücs, Zs. Fülöp:
Activation cross section measurement of the ¹⁴N(p,γ)¹⁵O astrophysical key reaction
Physical Review C 105 (2022) L022801

DOI: https://doi.org/10.1103/PhysRevC.105.L022801

Published: 3 February 2022

Abstract

Background: $14N(p,\gamma )15O$ is one of the key reactions of nuclear astrophysics, playing a role in various stellar processes and influencing energy generation of stars, stellar evolution, and nucleosynthesis. For a reliable reaction rate calculation, the low-energy cross section of $14$$N(p,\gamma )15O$must be known with high accuracy. Owing to the unmeasurable low cross sections, theoretical calculations are unavoidable.

Purpose: High-precision experimental cross section data are needed in a wide energy range in order to provide the necessary basis for low-energy extrapolations. In the present work, the total $14$$N(p,\gamma )15O$ cross section was measured with a method complementary to the available data sets.

Method: The cross section was measured with activation, based on the detection of the annihilation radiation following the ${\beta }^{+}$ decay of the reaction product $15$$O$. This method, which provides directly the astrophysically important total cross section, was never used for the $14$$N(p,\gamma )15O$ cross section measurement in the studied energy range.

Results: The nonresonant cross section was measured between 550 and 1400 keV center-of-mass energies with total uncertainty of about 10%. The results were compared with literature data using an $R$-matrix analysis. It is found that the cross sections measured in this work are in acceptable agreement with the two recent measurements only if the weak transitions—not measured in those works—are included.

Conclusions: The present data set, being largely independent from the other available data, can be used to constrain the extrapolated cross sections to astrophysical energies and helps to make the astrophysical model calculations more reliable.