Autoresonant Trap Mass Spectrometry (ART MS) for remote sensing applications

Abstract

A novel mass spectrometer is described that uses purely electrostatic fields to store ionized gases within a cylindrical ion trap. Ions are generated directly inside the trap by electron ionization of gas molecules. An anharmonic trapping potential well confines the ion trajectories of all ion masses, and of a wide range of initial energies, to stable oscillatory motions along the axis of the trap. Mass selective ejection is achieved through a novel autoresonant energy pumping process. The new mass spectrometer has unlimited mass range, good sensitivity at high and ultrahigh vacuum levels, very fast scan rates, compact construction, and extremely low power requirements as it uses only static bias potentials and very small RF signal levels (in the 100 mV range). Small size, low power consumption, rugged construction and reliable operation make ART MS technology an ideal candidate for in situ mass spectrometry in a wide variety of remote sampling applications including harsh sampling environments. Fast mass spectra acquisition rates particularly attractive for sampling applications from fast moving platforms such as airplanes, rockets and boats.