https://doi.org/10.1140/epjd/e2005-00022-0
Pressure broadening parameters of the hydroxyl radical A 2Σ+ (υ' = 0) ← X 2Π3/2 (υ'' = 0) transitions at ca. 308 nm*
School of Chemical Engineering and Analytical Science, University of
Manchester, P.O. Box 88, Manchester, M60 1QD, UK
Corresponding author: a Vasili.Kasiutsich@manchester.ac.uk
Received:
3
November
2004
Revised:
21
December
2004
Published online:
8
February
2005
Pressure broadening widths and pressure-induced frequency shifts for the
hydroxyl radical Q11([see full textsee full text]), Q21([see full textsee full text]), Q11(2), Q21(2)
absorption lines in the A band at ca. 308 nm have
been determined in the presence of a variety of gases (N2, Ar, Ne and He). Hydroxyl radicals were formed using either a microwave discharge or a
vacuum ultra-violet photolysis of water vapour and were detected using
direct absorption spectroscopy with a bandwidth normalised noise equivalent
absorption sensitivity of
Hz-1/2. A tunable
external cavity diode laser at 835 nm and a single-frequency continuous-wave
intracavity frequency-doubled diode laser at 488 nm were used to produce
tunable continuous-wave light at 308 nm by sum-frequency generation in a
crystal.
PACS: 33.70.Jg – Line and band widths, shapes, and shifts / 33.20.Lg – Ultraviolet spectra / 42.55.Px – Semiconductor lasers; laser diodes / 42.65.Ky – Frequency conversion; harmonic generation, including higher-order harmonic generation
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005