aosco (01)

Abstract

As of 5 August, 2015, Los Gatos Research (LGR) CO/H2O/N2O analyzer instruments (COANALYZERs) were deployed in the Atmospheric Radiation Measurement (ARM) Aerial Facility (AAF), the third ARM Mobile Facility (AMF3) Aerosol Observing System (AOS), Eastern North Atlantic (ENA) AOS, and Mobile AOS (MAOS-C). The N2O/CO analyzer uses LGR’s patented Off-axis ICOS technology, which employs a high-finesse optical cavity as the measurement cell. LGR’s technology has many proven advantages over conventional first-generation cavity ringdown spectroscopy (CRDS) techniques. In brief, since the laser beam does not have to be resonantly coupled to the measurement cell, precise beam alignment is not critical. Mentors can disassemble the cell for cleaning (CAREFULLY) the front surface mirrors. Analyzers are relatively inexpensive and inherently robust thermally and mechanically. In addition, since LGR’s technology can record reliable absorption spectra over a far wider range of optical depths (absorbance values) than CRDS, LGR analyzers provide measurements over a much wider range of mixing ratios (gas concentrations). The N2O/CO analyzer includes an internal computer that sends real-time data to the local instrument computer through its digital (RS-232) output.