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  • 1 Rijksuniversiteit Gent Institute for Nuclear Sciences Proeftuinstraat 86 B-9000 Gent (Belgium)
  • | 2 Central Research Institue for Physics H-1525 Budapest (Hungary)
  • | 3 University of Rabat Faculty of Sciences Maroc
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Abstract  

Some methods described in the literature for the determination of α in the 1/E1+α epithermal neutron spectrum are critically reviewed with respect to their accuracy. The multi resonance—detector method with Cd-covered irradiations, as used by SCHUMANN and ALBERT, is generalized by subtracting the epithermal 1/v-tail and by introducing the effective resonance energy, as defined by RYVES. The two-detector method of RYVES is modified by using Cd-ratio measurements, thus eliminating the introduction of systematic errors due to the inaccuracy of absolute nuclear data. The adapted methods are applied in channel 15 of the Thetis reactor (Gent).