Differential cross section measurements of the 18O(p, a0)15N reaction at 170º and 160º, in the energy range Ep=1-2MeV

Abstract

In the present work, the differential cross-sections of the ¹⁸O(p,α0)¹⁵N reaction were determined using the absolute measurement technique, in the proton energy range Ep=1–2 MeV for NRA purposes. The experiment was carried out in energy steps of 10 or 20 keV. Two detection angles, 170° and 160°, were measured, employing 500 μm thick Surface-Barrier-Back-Scattering detectors in a high-precision goniometric chamber. The target, a thin layer of Ta₂O₅ highly enriched in 18O, was deposited ona thick tantalum foil via anodization. Its thickness was provided by the manufacturer and independently verified experimentally using the ¹⁸O(d,α0) reaction. SIMNRA simulations were performed to determine the Q•Ω value, incorporating a pile-up calculation routine. The obtained results were compared with previously published data, allowing for a comprehensive analysis of both similarities and discrepancies. The reaction’s differential cross-section was determined using the absolute measurement technique. The final results revealed larger cross-section values compared to the existing literature ones. Some of the observed discrepancies were attributed to inaccuracies in the database entries. These coherent differential cross-section datasets are expected to facilitate the extension of the existing SigmaCalc evaluation of the ¹⁸O(p,α0) reaction to higher energies in the near future.