Developing a detection method of environmental 244Pu

The long-lived radionuclide 244Pu (t1/2=80.8±1.0 Ma) is a candidate for the detection as a live remnant of close-lying and relatively recent supernovae in geological records on the earth. We will present the development of an AMS method for measuring 244Pu at the low abundance levels which are expected for natural 244Pu. For artificial samples prepared from chemically pure reagents a sensitivity of more than 3 × 10−6 counts in detector per atom in sputter target was achieved. For true sediment samples the detector background induced by chemical impurities and possible cross contamination from high level standards were identified as the present limitations.