C. Arpesella et al., GAMMA-RAY ACTIVITY OF NEODYMIUM SAMPLES, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 372(3), 1996, pp. 415-424
The gamma ray activity of three samples of natural neodymium has been
measured and the concentration of radioactive elements from uranium an
d thorium chains as well as that from radioactive isotopes of lantaniu
m and lutetium has been quantitatively determined. All the samples sho
w significant contaminations up to p.p.m.