HR: 1340h
AN: A13C-0937    [Abstracts]
TI: Cavity-Enhanced Quantum-Cascade Laser-Based Instrument for Trace gas Measurements
AU: * Provencal, R
EM: r.provencal@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AU: Gupta, M
EM: m.gupta@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AU: Owano, T
EM: t.owano@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AU: Baer, D
EM: d.baer@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AU: Ricci, K
EM: k.ricci@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AU: O'Keefe, A
EM: a.okeefe@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue, Suite 3, Mountain View, CA 94041 United States
AB: An autonomous instrument based on Off-Axis Integrated Cavity Output Spectroscopy has been successfully deployed for measurements of CO in the troposphere and tropopause onboard a NASA DC-8 aircraft. The instrument consists of a measurement cell comprised of two high reflectivity mirrors, a continuous-wave quantum-cascade laser, gas sampling system, control and data acquisition electronics, and data analysis software. The instrument reports CO mixing ratio at a 1-Hz rate based on measured absorption, gas temperature and pressure using Beer's Law. During several flights in May-June 2004 and January 2005 that reached altitudes of 41000 ft, the instrument recorded CO values with a precision of 0.2 ppbv (1-s averaging time). Despite moderate turbulence and measurements of particulate-laden airflows, the instrument operated consistently and did not require any maintenance, mirror cleaning, or optical realignment during the flights. We will also present recent development efforts to extend the instrument's capabilities for the measurements of CH4, N2O and CO in real time.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005