1 - IAEA Nuclear Data Services

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effect on the half-life of 55m U (T,, = 26min) has been undertaken.
n
Preliminary results indicate a very large effect, amounting to about
6% between two extreme cases.
6» Integral cross sections measurements and nuclear data re­
lated to reactors»
6.1 . Evaluation of nuclear data for activation detectors.
A. FABRY,P.P. DAMLE, D.LANGELA, H. VANDÏNBROECK
The application of the spectral index technique in thermal and
fast reactors requires an accurate description of differential
energy cross section for activation detectors.
Excellent papers have been published on nuclear data related
to fissile and structural materials considered in reactor cal­
culations, but no counterpart seems to exist for activation de­
tectors, except in the case of threshold reactions. A systematic
compilation and evaluation effort has therefore been undertaken
to fulfill the requirement, in close connection with reactor
physics programmes. The report Big 421 £ 1 J presents recommanda­
tions for the reactions : 1 Dy(n, v) 1é5g Dy, 151 Eu(n, v) 152m Eu,
176 Lu(n, v ) 177 ^Lu, 191 lr(n,v) 192 eir, 193 Ir(n,v ) 19 ^Ir,
115 ln(n,v) 1l6m ln, 197 Au(n, v ) 1 9 V 175 Lu(n, v ) 176m Lu and
W(n,v ) W in view of their use in thermal reactors (éner­
gie below about j?0 eV).
A further paper ¿ 2 J soon to be published gives both differen­
tial and multigroup recommended croes section sets for the reac-
tions 115 ln(n,v ) 1l6 «Inf 197 Au(n,vV 98 Au, l86 W(n,v ) 18? W,
159 La(„,v )^°La, 55 Mn(n, v ) 56 Mn, 198 Pt(n,v ) 1 "*Pt and 63 C„(n, V) 64 Cu
over the whole neutron energy range 0,001 eV - 10 MeV for the
application in fast reactor spectra.