Joint Institute for Nuclear Research Relativistic ... - Index of - JINR

STUDIES OF DEUTERON AND NEUTRON CROSS-SECTIONS IMPORTANT
FOR ADS
V. Wagner, M. Suchopár, O. Svoboda, J. Vrzalová
for the collaboration "Energy and Transmutation of RAW"
Nuclear Physics Institute of ASCR, 250 68 Řež, Czech Republic
E-mail: wagner@ujf.cas.cz
The collaboration Energy and Transmutation of Radioactive Waste uses different setups
consisting of lead, natural uranium and graphite irradiated by relativistic protons and
deuterons to study transmutation of radioactive materials by produced neutrons. The
activation samples are used to determine integral of proton or deuteron beams and also
produced neutron flux in different places of experimental set-ups. Unfortunately almost no
experimental cross-section data for deuterons with GeV energies are available. The similar
situation is also for threshold (n,xn) reactions of neutrons with higher energies. Therefore we
carried out series of experiments devoted to determination of deuteron reactions on copper
during uranium target QUINTA irradiations by deuterons with energies from 1 GeV up to 8
GeV. The cross-sections of various threshold reactions were studied by means of different
quasi-monoenergetic neutron sources with possible energies from 14 MeV up to 100 MeV.
As it was already mentioned, the cross-sections of deuteron reactions on copper were
measured during several irradiations of big natural uranium target QUINTA. Values of
deuteron cross-section for energies of 1, 2, 4, 6 and 8 GeV were obtained. The beam integral
was determined mainly by aluminum foil and therefore accuracy of our values are correlated
to known experimental values of deuteron reaction Al(α,3p,2n) cross section on aluminum.
Only this reaction was measured. This and other sources of systematic uncertainties will be
discussed in detail.
The cross-sections of many neutron reactions important for our activation detectors are
missing. To improve situation we started a program of such cross-sections measurements by
means of quasi-monoenergetic neutron sources. We use two such sources. The first facility is
the neutron source based on the cyclotron at the Nuclear Physics Institute of ASCR, Řež. It
provides neutron beams in the energy range from 14 MeV up to 35 MeV. The second neutron
source is built around the cyclotron at TSL Uppsala. This facility provides neutron beam in
the energy range from 14 MeV up to 200 MeV. We studied mainly cross-sections of neutron
reactions on gold, aluminum, bismuth, cobalt and yttrium. We studied population of ground
and isomeric states separately. The case of yttrium will be discussed in detail.
130