1 - IAEA Nuclear Data Services

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.6. On 239 Pu
A series of neutron scattering measurements on
259
^-\Pu
were started at low primary neutron energies. For these
experiments an especially developped "low threshold"
neutron time-of-flight detector is in use. The detection
threshold corresponds to a neutron energy of about
40 keV. For the evaluation of the neutron scattering
cross sections it is necessary to subtract from the
measured spectra the contribution of the fission neutrons.
The fission spectrum was measured with primary
neutron energies around 60 keV. So far angular distributions
of neutrons from
259
•'•'Pu have been measured at
incoming energies of 0.4, 0.3 and 0.2 MeV.
.7. Experimental Equipment
A detecting system consisting of four counters for
simultaneous detection of neutrons scattered at different
angles was brought into operation. So far only
three counters were used for measuring neutron angular
distributions, while the fourth was used as a
neutron time-of-flight monitor. The general lay-out
of the experimental arrangement is shown in fig. 5.
Ion Source Test Facility
K.H. Bbckhoff, A. Crametz
The first stage of the 150 keV accelerator was put
in operation. Protons of about 1 mA have been accelerated
to 30 keV and sharply focussed onto a graphite
target.
Linear Accelerator
Total Gross Sections
.1. Resonance Range
K.H. Bôckhoff, V. Kolar
?40
The measurements and analysis of the neutron total