Radioactive decay of 217Pa

The radioactive decay of Pa-217 was investigated by means of alpha-gamma-spectroscopy. Fine structure in the ground-state alpha-decay was established. Ambiguities in the fine structure of the alpha-decay of the previously known isomeric state could be clarified by alpha-gamma-coincidence measurements. A previously unknown alpha-transition of E-alpha = (8306 +/- 5) keV was detected and identified by means of delayed alpha-alpha- and coincidence measurements. A second isomeric state decaying by alpha-emission was not observed. The quality of the previously reported data of the alpha-decay fine structure of Th-217 was improved.