title: Laser-induced fluorescence of Ba+ ions trapped and mass-selected in a Fourier transform ion cyclotron resonance mass spectrometer.
abstract: We present the design and preliminary results from a Fourier transform ion cyclotron resonance (ICR) mass spectrometer developed for the direct detection of UV/visible laser-induced fluorescence of trapped, mass-selected, gas-phase ions. A 3 T superconducting magnet and an open-ended multi-section cylindrical Penning trap capture and confine ions created by electron impact or laser desorption. Azimuthal quadrupolar excitation in the presence of ion/neutral collisions cools, axializes and mass selects ions as they fill the trap. A pulsed dye laser pumped by an Nd:YAG laser provides electronic energy excitation. A Brewster window and baffles on each side of the vacuum chamber reduce the scattered light from the excitation laser. Laser-induced fluorescence is collected from mirrors and lenses and directed through a quartz window and fiber-optic bundle to a photomultiplier. The ICR and optical events are controlled by a modular ICR data station and GPIB and RS-232 interfaces. An excitation spectrum is demonstrated for atomic Ba+ ions, and should extend to laser-induced fluorescence of virtually any stable positive or negative gas-phase ions of arbitrary molecular weight: molecular or quasimolecular ions, fragment ions, adduct ions, and ions formed from ion/molecule reactions.
authors.affiliation: Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee 32310, USA.
authors.forename: G Z
authors.initials: GZ
authors.lastname: Li
authors.forename: B A
authors.initials: BA
authors.lastname: Vining
authors.forename: S
authors.initials: S
authors.lastname: Guan
authors.forename: A G
authors.initials: AG
authors.lastname: Marshall
mesh_terms: D001464:Barium / Q000737:chemistry*; D017357:Cyclotrons; D004574:Electromagnetic Fields; D005453:Fluorescence; D005583:Fourier Analysis; D007834:Lasers; D013058:Mass Spectrometry / Q000295:instrumentation*; D008970:Molecular Weight
chemical_list: D001464:Barium