https://doi.org/10.1051/epjconf/20122104005
Scissors Mode in Gd Nuclei
1
Charles University in Prague, CZ-180 00 Prague 8, Czech Republic
2
North Carolina State University, Raleigh, NC 27695
and Triangle Universities Nuclear Laboratory, Durham, NC 27708
3
Lawrence Livermore National Laboratory, Livermore, CA 94551
4
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
a e-mail: kroll@ipnp.troja.mff.cuni.cz
Spectra of γ rays following neutron capture at isolated resonances of 6 stable Gd isotopes were measured with highly segmented BaF2 detector DANCE at the Los Alamos LANSCE spallation neutron source. The main emphasis was put on studying the γ-cascade decay of neutron resonances to get unique information on photon strength. An analysis of the accumulated γ-ray spectra within the extreme statistical model leads to an inescapable conclusion that scissors mode resonances are built not only on the ground-state, but also on excited levels in all product nuclei studied. The results on summed B(M1)↑ strength and energy of the scissors mode are compared with systematics of scissors mode parameters for the ground-state transitions deduced from nuclear resonance fluorescence measurements. A specific feature of our experiments is the investigation of scissors mode of odd nuclei, for which the nuclear resonance fluorescence provides only limited information.
© Owned by the authors, published by EDP Sciences, 2012