High-resolution mass-analyzed threshold ion spectrum of Argon obtained on beamline 9.0.2.2

Technical Report · Tue Apr 01 04:00:00 EST 1997

DOI:https://doi.org/10.2172/604276· OSTI ID:604276

Hsu, C. W.; Lu, K. T. ^[1]; Evans, M. ^[2]

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1. Ernest Orlando Lawrence Berkeley National Lab., CA (United States)
2. Ames Lab., IA (United States); and others

The first mass analyzed threshold ion (MATI) spectrum using dc electric fields and a continuous wave light source has been obtained on End Station 2 of the Chemical Dynamics Beamline (9.0.2.2) at the Advanced Light Source. MATI provides researchers with fundamental spectroscopic information about atomic and molecular ions with the added advantage of mass analysis. The MATI technique involves the detection of ions formed by field ionization of long-lived high-n Rydberg states approaching an ionization threshold. The MATI apparatus consists of a differentially pumped supersonic molecular beam source, a photoionization region followed by a series of electrostatic lenses, a quadrupole mass spectrometer, and a Daly-type detector. The MATI technique can be used to probe the Rydberg states approaching an ionization continuum and yield information about the lifetimes of these states. In addition, MATI could be used to obtain the spectrum of a single species present in a sample mixture due to the mass selective nature of the experiment. MATI could also be used to form mass selected and state specific ions for use in ion molecule reaction experiments.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 604276
• Report Number(s): LBNL--39981; ON: DE97007345
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ARGON
ION SPECTROSCOPY
RYDBERG STATES
THRESHOLD ENERGY