1 - IAEA Nuclear Data Services

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The experimental points have been fitted by a sum of even
order Legendre polynomials. The best fits obtained including
polynomials to the 6th order seem to agree better with the
experimental points.
Taking into account this result, a possible presence of more
reaction mechanism is suggested.
1«4. Neutrons from Am-Be sources
The neutron energy spectrum of an Am-Be source has been measured
using a particular fast-neutron spectrometer. High efficiency
and good energy resolution (AEn«0.3 MeV at En = 10 MeV) was
achieved.
The preliminary results evidenced the detailed structure of
the spectrum.
Measurements are in progress in order to obtain the neutron
spectrum with high accuracy and very good statistics. Results
are compared with other measurements obtained with Pu-Be [ 3 J
and Po-Be[4] sources.
1.5. Time of flight spectrometer
A time of flight neutron spectrometer has been realized in
order to study elastic and inelastic neutron scattering on
various nuclides with our 2 MeV Van de Graaff. The incoming
neutron beam is obtained by means of the d-d reaction in a
gas target.
The associate particle method is used as a start signal using
solid state detectors with suitable time pick-off. Neutrons
are detected by a liquid organic scintillator with y-* 1
discrimination.
Resolving time of a few ns has been obtained and we are trying
to improve it.
1.6. A diffraction model applied to the reaction 26 Mg( 3 He,a ) 25 Mg
Angular distributions have been measured for the five groups