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Aerodyne Research mobile infrared methane monitorAn improved real-time methane monitor based on infrared absorption of the 3.39 micron line of a HeNe laser is described. Real time in situ measurement of methane has important applications in stratospheric and tropospheric chemistry, especially when high accuracy measurements can be made rapidly, providing fine spatial-scale information. The methane instrument provides 5 ppb resolution in a 1 sec averaging time. A key feature in this instrument is the use of magnetic (Zeeman) broadening to achieve continuous tunability with constant output power over a range of 0.017/cm. The instruments optical absorption path length is 47 m through sampled air held at 50 torr in a multipass cell of the Herriott (off-axis resonator) type. A microprocessor controls laser frequency and amplitude and collects data with minimal operator attention. The instrument recently has been used to measure methane emissions from a variety of natural and artificial terrestrial sources.
Document ID
19920069550
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Mcmanus, J. B.
(NASA Headquarters Washington, DC United States)
Kebabian, P. L.
(NASA Headquarters Washington, DC United States)
Kolb, C. E.
(Aerodyne Research, Inc. Center for Chemical and Environmental Physics, Billerica, MA, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1991
Subject Category
Instrumentation And Photography
Meeting Information
Meeting: Measurement of Atmospheric Gases
Location: Los Angeles, CA
Country: United States
Start Date: January 21, 1991
End Date: January 23, 1991
Accession Number
92A52174
Distribution Limits
Public
Copyright
Other

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