Activation Cross Sections for 14-Mev Neutrons

Abstract

Cross sections for several nuclear reactions induced by 14-Mev neutrons were measured by the activation method. The number of activated atoms was determined by absolute beta-counting. Corrections for finite sample thicknesses were determined experimentally in every case. Cross sections for the following reactions were measured: (n t 2n) for

Energy Spectrum of Alpha Particles fromLi7+datEWeber1 1958Phys. Rev.15000View full textAdd to dashboardCite

“…4 The Q values obtained by both groups of workers were in rough agreement with an excitation energy of 0.95 Mev as found from other reactions. 1,6 Ciier and Jung, 2 using nuclear emulsion technique with partial magnetic separation, also report an a group corresponding to an excited state in He 5 , 2.5±0.2 Mev above the ground state.…”

Further tests of the Weisskopf-Ewing exciton model

“…In addition to the calculation of the excitation functions, we obtain the neutron emission spectrum from the n+56Fe reaction at 14. 36 MeV in both the present model and the REK theoly and compare them to the experimental spectra. The degree of agreement achieved here, points to the adequacy of the WE exciton model.…”

(n, p) Reaction for Gold

“…The energy uncertainty introduced by the slight desiccation of the plates, in vacuum for about 20 minutes, may be estimated by interpolation between the "wet emulsion" values of Lattes et al and Rotblat's calibration for plates desiccated for two hours. 4 This uncertainty does not exceed 50 kev at 14 Mev and diminishes with the proton energy.…”

“…Emulsion ranges were directly converted to energies using the classic calibration of Lattes, Fowler, and Cuer. 4 Although the plate housing was evacuated to eliminate proton energy loss between gold and plates, the emulsion calibration employed was that appropriate to emulsion in humidity equilibrium with the atmosphere. The energy uncertainty introduced by the slight desiccation of the plates, in vacuum for about 20 minutes, may be estimated by interpolation between the "wet emulsion" values of Lattes et al and Rotblat's calibration for plates desiccated for two hours.…”