Unified Absolute Differential Cross Sections for Neutron Production by the Hydrogen Isotopes for Charged-Particle Energies Between 6 and 17 MeV

An absolute scale for the differential cross sections of the reactions /sup 3/H(p,n)/sup 3/He, /sup 2/H(d,n)/sup 3/He, and /sup 3/H(d,n)/sup 4/He, measured for incident energies between 6 and 17 MeV, was established with the aid of a calibrated time-of-flight system. Accurate charged-particle reference cross sections were intercompared so that a common scale with an uncertainty of +- 1.5% was obtained. By interchange of the target and beam nuclei, data were obtained at 180 deg in the original system for several cases. The new data were analyzed together with the previous data, and Legendre coefficients were extracted to permit presentation of the data between approximately 5 and 20 MeV; previous evaluations were thus extended and partly revised. The typical shape error of the angular distributions, as given by the Legendre coefficients, is <3% over the entire angular range. In addition, data on the neutron production at zero degrees by breakup are given for the p-T and d-D reactions. By correcting the previous counter telescope data for the /sup 1/H(n,n)/sup 1/H cross sections (according to more recent phase-shift analyses), scale ambiguities of approximately 3% were resolved; these phase shifts were thus indirectly verified up to neutron energies of approximately 16 MeV. However,more » at higher energies (above aproximately 23 MeV) for /sup 3/H(d,n)/sup 4/He data, the corrected neutron counter telescope data deviated from the present analysis by approximately 5%. Whether or not this difference is caused by the /sup 1/H(n,n)/sup 1/H reference cross section used is open to further investigations. 16 figures, 18 tables, 73 references.« less