A quadrupole ion trap mass spectrometer for in-situ UHV analyses on Earth and other planetary environments

Abstract:

The JPL quadrupole ion trap mass spectrometer presents an exceptional opportunity for combining cutting edge terrestrial geochemical research with the next generation of extraterrestrial science. The QIT is a small mass spectrometer that filters particles of different mass by electron ionization and subsequent separation with a quadrupole RF field. The latest version is capable of achieving very high resolution (R > 1000) without an increase in power consumption through the addition of a dipole RF to augment the primary quadrupole field. Crucially, we demonstrate the ability to achieve this resolution with high sensitivity (> 10¹⁴ cps/Torr), and at UHV without the addition of a cooling gas. In this mode, the high sensitivity and extremely low background allow the measurement of a large number of species in very small samples.

Most laboratory instruments are too heavy, large, and energy-intensive to fly on spacecraft in their optimal forms. As a result, instruments for spaceflight have traditionally been heavily-modified versions of terrestrial instruments, designed to be lighter, smaller, and more efficient than their terrestrial counterparts, at the expense of analytical capabilities. The JPL QIT, in contrast, weighs less than 1 kg, is only a few cm in size, and consumes less than 30W. Only the accompanying UHV system and supporting electronics must be extensively redesigned for spaceflight, and NASA already possesses pumps capable of fulfilling this need. The opportunity for parallel development for terrestrial and extraterrestrial labs and the capability of direct comparison between planetary science and terrestrial geochemistry will benefit both fields.