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  • Development of a laser-photofragmentation laser-induced fluorescence instrument for the detection of nitrous acid and hydroxyl radicals in the atmosphere
Title: Development of a laser-photofragmentation laser-induced fluorescence instrument for the detection of nitrous acid and hydroxyl radicals in the atmosphere
Abstract. A new instrument for the measurement of atmosphericnitrous acid (HONO) and hydroxyl radicals (OH) has been developed usinglaser photofragmentation (LP) of HONO at 355 nm after expansion into alow-pressure cell, followed by resonant laser-induced fluorescence (LIF) ofthe resulting OH radical fragment at 308 nm similar to the fluorescenceassay by gas expansion technique (FAGE). The LP/LIF instrument is calibratedby determining the photofragmentation efficiency of HONO andcalibrating the instrument sensitivity for detection of the OH fragment. Inthis method, a known concentration of OH from the photo-dissociation ofwater vapor is titrated with nitric oxide to produce a known concentrationof HONO. Measurement of the concentration of the OH radical fragmentrelative to the concentration of HONO provides a measurement of thephotofragmentation efficiency. The LP/LIF instrument has demonstrated a1σ detection limit for HONO of 9 ppt for a 10 min integration time.Ambient measurements of HONO and OH from a forested environment and an urbansetting are presented along with indoor measurements to demonstrate theperformance of the instrument.  more » « less
Award ID(s):
1827450 1012161
PAR ID:
10303176
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Atmospheric Measurement Techniques
Volume:
14
Issue:
9
ISSN:
1867-8548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. ; (, Atmospheric Measurement Techniques)
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  2. ; ; ; ; (, Plasma Sources Science and Technology)
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  3. ; ; ; ; ; ; ; ; ; ; et al (, Atmospheric Chemistry and Physics)
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  5. ; ; ; ; ; ; (, Journal of Physics D: Applied Physics)
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