[ RadSafe ] Europium-252 identified instead of Bismuth-214

[Michael McNaughton]

Dear Radsafers

I have some soil samples for which I think Bismuth-214 is incorrectly 
identified as Europium-252. Is this a well-known problem?

The gamma-spec software found a small peak near 1408 keV and reported 
it as 0.4 pCi/g of Europium-252, though it did not find any other 
Europium-252 peaks. The sample contains about 3 pCi/g of Bismuth-214, 
and has large peaks at 609 keV, 1120 keV, and 1765 keV, so I think 
the small peak at 1408 keV is probably from Bismuth 214. The relative 
sizes of the peaks correspond to the relative probabilities of decay 
for Bismuth-214.

I would be interested in discussing this problem with gamma-spec experts.

Thanks, mike

Mike McNaughton
Los Alamos National Lab.
email: mcnaught at LANL.gov or mcnaughton at LANL.gov
phone: 505-667-6130; page: 505-664-7733