Program - Brookhaven National Laboratory

cascade from the decay of highly excited compound nucleus states like neutron resonances show differences
dependent on the initial spin. This results in a difference in the multiplicity distribution which can be
exploited. We have used the 4π total absorption calorimeter (TAC) at the neutron time-of-flight facility
n TOF at CERN to determine the spins of resonances formed by neutrons incident on a metallic 87 Sr
sample by measuring the gamma multiplicity distributions for the resolved resonances. The first results
will be presented here.
FF 3 11:20 AM
Measurements of Partial γ-ray Cross Sections in 60 Ni(n, xnypzαγ) Reactions
N. Fotiades, M. Devlin, R. C. Haight, T. Kawano, S. Kunieda ∗ , R. O. Nelson.
Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Absolute partial cross sections for production of discrete γ-rays using 60 Ni(n, xnypzαγ) reactions with
x ≤ 3, y ≤ 2 and z ≤ 4 in a total of 20 reaction channels were measured. The data were taken using the
GEANIE spectrometer comprised of 20 high-purity Ge detectors with BGO escape-suppression shields.
The broad-spectrum pulsed neutron beam of the Los Alamos Neutron Science Center’s (LANSCE) WNR
facility provided neutrons in the energy range from 0.2 to 300 MeV. The time-of-flight technique was
used to determine the incident neutron energies. Partial γ-ray cross sections have been measured for
a total of 57 transitions and for neutron energies 1 MeV< En