Measurement of the $^\text{nat}$C(n,p) and $^\text{nat}$C(n,d) reactions from n_TOF at CERN

TL;DR

This study measures the energy-dependent cross sections of $^ ext{nat}$C(n,p) and (n,d) reactions up to 25 MeV at CERN's n_TOF, providing more accurate data and comparing it with theoretical models and existing evaluations.

Contribution

First measurement of the energy dependence of these reactions on natural carbon at n_TOF, with improved accuracy and broader energy range than previous data.

Findings

Higher accuracy and wider energy range than existing literature.

Significant disagreement with current evaluation libraries.

Good agreement with TALYS-2.0 theoretical predictions.

Abstract

The energy dependence of the cross section of the (n,p) and (n,d) reactions on $^\text{nat}$C has been studied for the first time at the n_TOF facility at CERN, from the particle detection threshold up to 25 MeV. The measurement was performed with two telescopes made of position-sensitive silicon $\Delta E$-$E$ detectors, covering the angular range from 20{\deg} to 140{\deg}. A detector efficiency has been determined by means of Monte Carlo simulations of the experimental setup. Various assumptions on the angular distributions and branching ratios of the excited levels of the residual $^{11}$B, $^{12}$B, $^{13}$B nuclei were considered. In particular, theoretical calculations based on the TALYS-2.0 code were used and the systematic uncertainties in the analysis results were determined from the variations in these distributions. The n_TOF data on the (n,p) and (n,d) reaction on carbon are characterized by a higher accuracy and wider energy range than currently available in literature. A comparison with current evaluations from different libraries reveals a rather significant disagreement with the n_TOF results, while a remarkable agreement is observed with the prediction of TALYS-2.0 for this light element.