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Widely Tunable Infrared Laser Spectrometer for Measurement
of Isotopic Ratios of Carbon Cycle Gases--Aerodyne Research,
Inc., 45 Manning Road, Billerica, MA
01821-3934; 978-663-9500
Dr. Mark S. Zahniser,
Principal Investigator
Dr. Charles E. Kolb,
Business Official
DOE Grant No. DE-FG02-00ER82938
Amount: $100,000
Isotopic ratio variations
in the key carbon cycle gases CO2 and CH4 are critical to
understanding the atmospheric sources and sinks of these important greenhouse
gases. Currently, the major method to
measure these ratios, isotopic mass spectrometry, requires extensive sample
preparation and very expensive hardware.
A widely tunable mid-infrared laser spectrometer could characterize
isotopic signatures of CH4 and CO2 sources and sinks with
less labor and expense. Recent advances
in the use of the non-linear material, periodically poled lithium niobate
(PPLN), pumped with non-cryogenic near infrared laser sources can be extended
to produce tunable, single mode laser radiation over the absorption bands of
the major isotopomers to yield isotopic ratios for CO2 (13C/12C
and 18O/16O) and CH4 (13C/12C
and D/H). A laser spectrometer designed
to exploit this advance and produce high precision isotopic ratios will be
designed (Phase I) and fabricated and tested (Phase II). Exploration of near infrared pump sources to
select those capable of producing high quality tunable radiation in strong
absorption bands of the main CO2 and CH4 isomers. Selection of the CO2 and CH4
isomer absorption features which will yield the most precise isotopic
ratios. Detailed spectrometer design
and signal processing algorithm development.
Commercial Applications and Other Benefits as described by the awardee: The development of an agile, robust,
non-cryogenic mid-infrared laser spectrometer capable of measuring a large
number of volatile organic carbon (VOC) air toxics for use in industrial
pollution monitoring and remediation.