New candidates for high spin isomeric targets

Experimental results of the accumulation and study of reaction mechanism of the de-excitation of high spin isomeric Ag-108m (J(pi) = 6(+)), Ho-166m (J (pi) = 7(-)) and Ta-180m (J(pi) = 9(-)) are discussed. Together with other isomers, such as targets Hf-178m2 (J(pi) = 16(+)), Re-186m (J(pi) = 8(+)), Am-242m (J pi = 5(-)), which can be produced by neutron-capture reactions o r in reactions involving heavy ions, they can possibly be used for new expe riments in nuclear physics. The large integral cross section for neutron ca pture (usually some barns) and enough cooling time allows the ground state of these isomers to completely decay due to their short half-life. The larg e integral de-excitation cross section (more 10 mb MeV) in inelastic gamma- quanta scattering allows for a successful measurement on a small number of atoms (<10(15)) and makes them candidates for gamma-laser on the nuclear le vels. (C) 1999 Elsevier Science B.V. All rights reserved.