COMB-ANCHORED, CAVITY RING-DOWN SPECTROSCOPY OF THE 1.27 μm BAND OF O2

Fleurbaey, Helene

Permalink

https://hdl.handle.net/2142/107446 Copy

Description

Title

COMB-ANCHORED, CAVITY RING-DOWN SPECTROSCOPY OF THE 1.27 μm BAND OF O2

Author(s)

Fleurbaey, Helene

Contributor(s)

Hodges, Joseph T.; Adkins, Erin M.; Reed, Zachary

Issue Date

26-Jun-20

Keyword(s)

Lineshapes, collisional effects

Abstract

New measurements of the $a^{1}\Delta_{\mathrm g} \leftarrow X^{3}\Sigma_{\mathrm g}^{-}$ band of oxygen (\chem{^{16}O_2}) at 1.27 $\mu$m will be presented, improving on a previous study [Mendonca et al., Atmos. Meas. Tech. 12, 35-50 (2019)]. Spectra were acquired by frequency-stabilized cavity ring-down spectroscopy over a 160 $\wn$ wave number range (7792 $\wn$ to 7952 $\wn$). The frequency axis was anchored to a Cs-clock-referenced optical frequency comb through a heterodyne beat note between the comb and the probe laser at about 20 points across the wave number range. The probe laser was phase locked to the frequency comb prior to measuring the beat note frequency in order to improve the accuracy, yielding a 10-Hz uncertainty in the ring-down cavity free spectral range and a 30-kHz absolute frequency uncertainty for all mode orders. Six air-broadened spectra were recorded, at pressures ranging from 3.3 kPa to 100 kPa. They were analyzed with custom multi-spectrum fitting software based on the HAPI python library, using the speed-dependent Nelkin-Ghatak profile. The resulting line shape parameters reveal important discrepancies with the HITRAN2016 values. These results will also be compared to those reported in recent studies by the Grenoble group [Konefał et al., JQSRT 241, 106653 (2020) and Tran et al., JQSRT 240, 106673 (2020)].

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

English

Permalink

http://hdl.handle.net/2142/107446

Owning Collections