title: Characterization of a near-room-temperature, continuous-wave quantum cascade laser for long-term, unattended monitoring of nitric oxide in the atmosphere.
abstract: We report on power, spectral linewidth, and mode purity for a cw 5.3 microm quantum cascade laser operated on a thermo-electric cooler. A totally noncryogenic nitric oxide monitor was constructed by integrating this laser with an astigmatic multipass cell and a thermo-electrically cooled infrared detector. The resulting instrument is capable of continuous unattended monitoring of ambient, atmospheric nitric oxide for several weeks with no operator intervention. The detection method was rapid sweep, direct absorption spectroscopy. A detection sensitivity of 0.03 parts in 10(9) is achieved with 30 s averaging time with a path length of 210 m, corresponding to an absorbance path length product of 1.5 x 10(-10) cm(-1).
authors.affiliation: Aerodyne Research, Inc., Billerica, Massachusetts 01821-3976, USA. ddn@aerodyne.com
authors.forename: David D
authors.initials: DD
authors.lastname: Nelson
authors.forename: J Barry
authors.initials: JB
authors.lastname: McManus
authors.forename: Scott C
authors.initials: SC
authors.lastname: Herndon
authors.forename: Joanne H
authors.initials: JH
authors.lastname: Shorter
authors.forename: Mark S
authors.initials: MS
authors.lastname: Zahniser
authors.forename: Stéphane
authors.initials: S
authors.lastname: Blaser
authors.forename: Lubos
authors.initials: L
authors.lastname: Hvozdara
authors.forename: Antoine
authors.initials: A
authors.lastname: Muller
authors.forename: Marcella
authors.initials: M
authors.lastname: Giovannini
authors.forename: Jérôme
authors.initials: J
authors.lastname: Faist