ABSTRACT
We describe a double-scattering experiment with a novel tagged neutron beam to measure differential cross sections for np backscattering to better than +/-2% absolute precision. The measurement focuses on angles and energies where the cross section magnitude and angle dependence constrain the charged pion-nucleon coupling constant, but existing data show serious discrepancies among themselves and with energy-dependent partial-wave analyses. The present results are in good accord with the partial-wave analyses, but deviate systematically from other recent measurements.
ABSTRACT
The double-differential cross sections for (n, px), (n, dx), (n, tx), (n, 3Hex) and (n, alphax) reactions in carbon have been measured at 96 MeV incident neutron energy. The various charged particles (inclusive spectra) were identified using deltaE-E techniques. From the experimental data, energy- and angle-differential as well as production cross sections were determined, and subsequently the partial and total kerma coefficients. The deduced partial and total kerma coefficients were compared to previous experimental results and theoretical calculations. The findings indicate that the deduced kerma coefficients for the hydrogen isotopes are in good agreement with those deduced from a previous measurement, and that the kerma coefficient values, in particular of the hydrogen isotopes, are systematically higher than values obtained from recent model calculations, which consequently resulted in a total kerma coefficient which is up to 30% higher than predicted by the calculations.