Prompt [gamma]-ray production cross sections were measured on a 48Ti sample for incident neutron energies from 1 MeV to 200 MeV. Partial [gamma]-ray cross sections for transitions in 45−48Ti, 45−48Sc, and 43−45Ca were determined. The observation of about 130 transitions from 11 different isotopes in the present work provides a demanding test of reaction model calculations, and is the first study in this mass region to extract partial [gamma]-ray cross sections for many different reaction channels over a wide range of incident neutron energies. The neutrons were produced by the Los Alamos National Laboratory spallation neutron source located at the LANSCE/WNR facility. The prompt-reaction [gamma] rays were detected with the large-scale Compton-suppressed GErmanium Array for Neutron Induced Excitations (GEANIE). Event neutron energies were determined by the time-of-flight technique. The [gamma]-ray excitation functions were converted to partial [gamma]-ray cross sections and then compared with model calculations using the enhanced GNASH reaction code. Compound nuclear, pre-equilibrium emission and direct reaction mechanisms are included. Overall the model calculations of the partial [gamma]-ray cross sections are in good agreement with measured values.

[Gamma]-ray excitation functions have been measured for the interaction of fast neutrons with 48Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction [gamma] rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial [gamma]-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial [gamma]-ray cross sections for transitions in {sup 47,48}Ti, 48Sc, and 45Ca have been determined. These results are compared to Hauser-Feshbach predictions calculated using the STAPRE code, which includes compound nuclear and pre-equilibrium emission. The partial cross sections for [gamma] rays, whose discrete [gamma]-ray cascade path leads to the ground state in 48Ti, 47Ti, 48Sc, and 45Ca have been summed to obtain estimates of the lower limits for reaction cross sections. Partial cross sections for unobserved [gamma]-rays are predicted from the STAPRE code. These lower limits are combined with Hauser-Feshbach calculations to deduce 48Ti(n, n')48Ti, 48Ti(n,2n)47Ti, 48Ti(n, p)48Sc, and 48Ti(n, [alpha])45Ca reaction channel cross sections.

Gamma-ray cross section standards for neutron-induced reactions are important in enabling the accurate determination of absolute cross sections from relative measurements of gamma-ray production. In our work we observed a need for improvement in these standards. In particular there are large discrepancies between evaluations of the {sup nat}Fe(n, n1'[gamma]) cross section for the 847-keV gamma ray. We have performed (1) absolute cross section measurements, (2) measurements relative to the {sup nat}Cr(n, n1'[gamma]) 1434-keV gamma ray, and (3) comparisons using measured total and elastic scattering cross sections to refine our knowledge of the Fe cross section and the closely linked inelastic channel cross section for Fe. Calculation of integral tests of the cross section libraries may indicate that adjustment of the angular distributions of the neutron elastic and inelastic scattering may be needed.

[Gamma]-ray excitation functions have been measured for the interaction of fast neutrons with [sup 48]Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction [gamma] rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial [gamma]-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial [gamma]-ray cross sections for transitions in [sup 47,48]Ti, [sup 48]Sc, and [sup 45]Ca have been determined. These results are compared to Hauser-Feshbach predictions calculated using the STAPRE code, which includes compound nuclear and pre-equilibrium emission. The partial cross sections for [gamma] rays, whose discrete [gamma]-ray cascade path leads to the ground state in [sup 48]Ti, [sup 47]Ti, [sup 48]Sc, and [sup 45]Ca have been summed to obtain estimates of the lower limits for reaction cross sections. Partial cross sections for unobserved [gamma]-rays are predicted from the STAPRE code. These lower limits are combined with Hauser-Feshbach calculations to deduce [sup 48]Ti(n, n')[sup 48]Ti, [sup 48]Ti(n,2n)[sup 47]Ti, [sup 48]Ti(n, p)[sup 48]Sc, and [sup 48]Ti(n, [alpha])[sup 45]Ca reaction channel cross sections.