108 research outputs found
Light-ion Production And Fission Studies Using The Medley Facility At Tsl
oS(FNDA2006)001 © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence
Light-ion production in the interaction of 96 MeV neutrons with oxygen
Double-differential cross sections for light-ion (p, d, t, He-3 and alpha)
production in oxygen, induced by 96 MeV neutrons are reported. Energy spectra
are measured at eight laboratory angles from 20 degrees to 160 degrees in steps
of 20 degrees. Procedures for data taking and data reduction are presented.
Deduced energy-differential and production cross sections are reported.
Experimental cross sections are compared to theoretical reaction model
calculations and experimental data at lower neutron energies in the literature.
The measured proton data agree reasonably well with the results of the model
calculations, whereas the agreement for the other particles is less convincing.
The measured production cross sections for protons, deuterons, tritons and
alpha particles support the trends suggested by data at lower energies.Comment: 21 pages, 13 figures, submitted to Phys. Rev.
Measurement of the Absolute Differential Cross Section for np Elastic Scattering at 194 MeV
A tagged medium-energy neutron beam has been used in a precise measurement of
the absolute differential cross section for np back-scattering. The results
resolve significant discrepancies within the np database concerning the angular
dependence in this regime. The experiment has determined the absolute
normalization with 1.5% uncertainty, suitable to verify constraints of
supposedly comparable precision that arise from the rest of the database in
partial wave analyses. The analysis procedures, especially those associated
with evaluation of systematic errors in the experiment, are described in detail
so that systematic uncertainties may be included in a reasonable way in
subsequent partial wave analysis fits incorporating the present results.Comment: 22 pages, 21 figures, submitted for publication in Physical Review
Measurement of the Absolute np Scattering Differential Cross Section at 194 MeV
We describe a double-scattering experiment with a novel tagged neutron beam
to measure differential cross sections for np back-scattering 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 (PWA). The present
results are in good accord with the PWA, but deviate systematically from other
recent measurements.Comment: 4 pages, 4 figure
Nucleon-induced reactions at intermediate energies: New data at 96 MeV and theoretical status
Double-differential cross sections for light charged particle production (up
to A=4) were measured in 96 MeV neutron-induced reactions, at TSL laboratory
cyclotron in Uppsala (Sweden). Measurements for three targets, Fe, Pb, and U,
were performed using two independent devices, SCANDAL and MEDLEY. The data were
recorded with low energy thresholds and for a wide angular range (20-160
degrees). The normalization procedure used to extract the cross sections is
based on the np elastic scattering reaction that we measured and for which we
present experimental results. A good control of the systematic uncertainties
affecting the results is achieved. Calculations using the exciton model are
reported. Two different theoretical approches proposed to improve its
predictive power regarding the complex particle emission are tested. The
capabilities of each approach is illustrated by comparison with the 96 MeV data
that we measured, and with other experimental results available in the
literature.Comment: 21 pages, 28 figure
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