U-Th-Ra

Our lab has a long history of U-series measurements. Our current focus is on U, Th, and Ra isotopes with the Neptune MC-ICP-MS. In addition to its 1 fixed and 8 moveable Faraday detectors is a MASSCOM secondary electron multiplier (SEM) equipped with a retarding potential quadrupole (RPQ). This enables abundance sensitivities of typically <50 ppb at 2 amu and SEM/Faraday yield of ~80+%, which is required for low abundance isotopes such as 230Th and 234U. We also commonly utilize an 10^13 ohm resistor for minor isotopes as an alternative to the SEM.