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New addition to the lab!

The Wadhwa Research Group has a new family member: A Thermo Neptune Plus multi-collector mass spectrometer!

Neptune Plus
Meenakshi Wadhwa and Vinai Rai, with newly installed Neptune Plus. Photo: ASU/Wadhwa. Click to enlarge.
Installed and set up next to the first Wadhwa Neptune, the Neptune Plus is now up and running, and ready to analyze.

How does it work?

The sample is ionized by stripping off electrons and directing the ions, using electrostatic lenses in a high vacuum, to an electromagnet (or other type of mass analyzer). The ions are then separated by atomic weight and directed to one or a series of detectors. The resulting signals are fed into a computer that calculates isotope ratios and analytical uncertainties.

The Neptune's plasma is as hot as the surface of the Sun, essential for stripping electrons to convert neutral atoms in meteorites to ions we can count to learn about the origin & evolution of our Solar System!

Lit plasma
Lit plasma. Photo: ASU/Wadhwa.
At about 6000K, (~10340F) the plasma is hot enough to atomize the sample and ionize most elements (except those with very high first ionization potentials like noble gases!) to singly charged ions & some doubly charged ones. Photo: ASU/Wadhwa.

In the video below, you can watch as the installation team mounts the 973 lb magnet around the very delicate flight tube: