1 - IAEA Nuclear Data Services
1 - IAEA Nuclear Data Services
1 - IAEA Nuclear Data Services
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- 37 -<br />
Precision Measurements of Excitation Functions of<br />
(n,p), (n,g) and (n,2n) Reactions Induced by<br />
13.5 - 14.7 MeV Neutrons.<br />
H.K. Vonach, W.G. Vonach, H. Münzer (Universitât<br />
ñünchen) un'd P. Schrammel (Ges. f. Strahlenforschung,<br />
Neuherberg)<br />
i o<br />
Excitation Functions for the reactions F (n,2n),<br />
24 Mg (n,p), 27 A1 (n,cü, 48 Ti (n,p), 51 V(n,a),<br />
65r. • / o \ 107. / - v 106mA : 115T / 0 v 114mT<br />
•Cu (n,2n), 'Ag (n,2n) Ag,. •'In (n,2n) In,<br />
181 Ta (n,2A) 108m Ta and 197 Au (n,2n) 196 Au were<br />
determined in 30 - 50 EeV steps iii the energy range<br />
13.50 - 14.7 MeV using the activation method. Neutrons<br />
from the D ;- T reactions (deuteron energy 0.12 MeV)<br />
were used to irradiate the samples. The gamma-activities<br />
produced by the reactions were measured with a large<br />
NaJ well crystal (statistical accuracy 0.2 - 0.5 %).<br />
Systematic errors were minimized by use of an accurate<br />
geometry (target sample distance 100 + 0.15 mm) and by<br />
use of an extremely light air-cooled target assembly<br />
minimizing the contribution of elastically scattered<br />
neutrons to the activation of the samples and by the<br />
use high-purity metallic samples. The attenuation of<br />
neutrons in the target and target assembly as well the<br />
intensity of the neutrons scattered elastically by<br />
target and target assembly was calculated as a function<br />
of the neutron emission angle (and corresponding neutron<br />
energy) and appropriate corrections applied. In this<br />
way an overall accuracy of about 1 % could be obtained<br />
for the relative cross-section CT(En)tf(14.7MeV) . Q^<br />
excitation functions are shown in fig. 1 to 8, crosssections<br />
are arbitarily normalized to unity at 14.7 MeV,<br />
the size of the data points corresponds to the statistical<br />
errors. The smooth curves are least square fits<br />
of first or second degree polynomials except for the<br />
24<br />
Mg (n,p) and Al (n,a) were definitely fine structure<br />
is present and the smooth curves were drawn according<br />
to "eye-inspection".