-53- Zn. In addition, all of the lsotopes under consideration except Pe” and °° fall on or to the left of the line of beta stability, suggesting the process of spallation as a possible source of production. Of course, their formation by lower energy neutron re- actions is also possible, although a greater number of elemental ~~ eer we OTR A eT RPie pate obser gemma Te Te re ee precursors would be required.