1 - IAEA Nuclear Data Services

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Some modifications concerning the sample geometry
have been made.
4.2.2. Calculations Concerning the Differential Cross Section
for Elastic Neutron Scattering
Two PORTEAN IV programs, BLATT-4 and ERRFIT, have been
written. BLATT-4 performs a least squares fit of the
Blatt and Biedenharn single level formula for the
differential elastic scattering cross section. ERRFIT
computes the error on the theoretical differential
cross section calculated with resonance parameters
obtained from BLATT-4 [25].
The program ELIESE-1 (JAERI-1096) has been modified
in order to be used in a least squares method to fit
the differential elastic neutron scattering cross
section by means of optical model and Hauser-Feshbach
calculations. The program is being tested.
4.2.3. Multiple Scattering Corrections for Elastic and
Inelastic Neutron Scattering Cross Section Data
Detailed tests of the programs MAGGIE and MOULD
(Aldermaston) have been made. Several errors in
MAGGIE concerning the score calculations have been
corrected. MAGGIE has been completed by a subroutine
which performs the correction of the measured inelastic
neutron peaks for contamination by multiple
elastic scatter. The iteration routine for the shape
correction of measured elastic angular distribution
has been extended to include the inelastic case. Calculations
of flux attenuation factors, shape corrections
for elastic and inelastic angular distributions,
and special score calculations have been performed
for Si (4.00 - 5.74 MeV) Polythene (4.00 - 4.78 MeV),
and 7 Li (1.10 - 2.30 MeV).