Program - Brookhaven National Laboratory

criteria for the reconstruction of the 293.6 K broadened cross sections is set to 0.01% in NJOY. Second,
a transmission and a primary capture yield being a simple functional of cross-sections, these observables
are analytically checked with NJOY code highlighting there is no bias. Finally, total capture yields are
simulated by a Monte Carlo technique inside CONRAD and checked for U238 at 1200K and Mn55 against
SAMSMC [3] nuclear data evaluation code. A good agreement can be achieved between the two codes
depending on the model used.
[1] C. De Saint Jean, B. Habert, O. Litaize, G. Noguere, C. Suteau, Proc. of Int. Conf. on Nucl. Data
ND2007, Nice, France, 2007. [2] R.E. MacFarlane and A.C. Kahler, Nucl. Data Sheets 111, 2739-2890
(2010). [3] N.M. Larson, K.N. Volev, Proc. of Int. Conf. on Nucl. Data ND2002, Seoul, Korea, 2002.
PR 55
10 B(n, Z) Measurements
T. N. Massey, James Ralston, Steven M. Grimes, Department of Physics and Astronomy, Ohio
University, Athens, OH 45701, USA. R.C. Haight, Los Alamos Neutron Science Center, Los Alamos
National Laboratory, Los Alamos, NM 87545, USA.
Four E Delta E telescopes were used at the LANSCE WNR (n,Z) station to investigate the production of
charged particles from 10 B. The telescope consisted of a gas proportional detector and a silicon surface
barrier detector. The flux was determined using a 238 U fission chamber. A clear measurement of the
ground state alpha group and first excited state was able to be done at these angles. Proton emission
was also observed. The proton branch was up to an order of magnitude larger than the ENDF/B-VII
evaluation. A simple R-matrix analysis has been performed on the available data.
PR 56
Characterization of a Be(p,xn) Neutron Source for Fission Yields Measurements
A. Mattera, P. Andersson, A. Hjalmarsson, M. Lantz, S. Pomp, V. Rakopoulos, A. Solders, J.
Valldor-Blücher, Uppsala University, Uppsala, Sweden. A. Prokofiev, The Svedberg Laboratory, Uppsala
University, Uppsala, Sweden. D. Gorelov, H. Penttilä, S. Rinta-Antila, University of Jyväskylä,
Jyväskylä, Finland. R. Bedogni, A. Gentile, INFN - LNF, Frascati, Italy. D. Bortot, M.V. Introini,
Politecnico di Milano, Milan, Italy.
We report on measurements performed at The Svedberg Laboratory (TSL) to characterize a proton-neutron
converter for fission yield studies. A 30 MeV proton beam impinged on a 5 mm water-cooled Beryllium
target. The setup was designed to reproduce the conditions at the IGISOL-JYFLTRAP facility (University
of Jyväskylä), where the neutron source will be used with the new high-intensity cyclotron for neutron
induced fission yields measurements of different actinides using a Penning trap [1].
Two independent experimental techniques have been used to measure the neutron spectrum: a Time of
Flight (ToF) system used to estimate the high-energy contribution, and a Bonner Sphere Spectrometer able
to provide accurate results from thermal energies up to 20 MeV. An overlap between the energy regions
covered by the two systems permits a cross-check of the results from the different techniques.
The ToF setup consisted of a liquid scintillator with good properties for n-γ discrimination [2]. Benchmarking
of the ToF technique was obtained by performing measurements with a polyethylene-moderated
target and with bare Beryllium targets of different thicknesses. Detailed Monte Carlo calculations of the
different experimental conditions have been performed and their comparison with the measured data will
also be shown.
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