High-resolution absorption cross sections of formaldehyde at wavelengths from 313 to 320 nm

2005 ◽  
Vol 7 (1) ◽  
pp. 79 ◽  
Author(s):  
Francis D. Pope ◽  
Carina A. Smith ◽  
Michael N. R. Ashfold ◽  
Andrew J. Orr-Ewing
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Absorption Cross

High-Resolution Measurements of the Absorption Cross-Sections for O3 and NO2

1997 ◽  
pp. 157-161
Author(s):  
Brion Jean ◽  
A. Chakir ◽  
B. Coquart ◽  
D. Daumont ◽  
A. Jenouvrier ◽  
...  
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Absorption Cross

High resolution VUV laser measurements of the CO A 1Π–X 1Σ+ (v’,0) absorption cross sections

1994 ◽  
Author(s):  
D. Malmasson ◽  
A. Vient ◽  
J. L. Lemaire ◽  
A. Le Floch ◽  
F. Rostas
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Absorption Cross ◽  
Laser Measurements

High resolution absorption cross sections for the a 2Π-X2 system of ClO

1977 ◽  
Vol 50 (1) ◽  
pp. 101-106 ◽  
Author(s):  
P.H. Wine ◽  
A.R. Ravishankara ◽  
D.L. Philen ◽  
D.D. Davis ◽  
R.T. Watson
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Absorption Cross

scholarly journals High-resolution absorption cross sections of C2H6 at elevated temperatures

2015 ◽  
Vol 1 ◽  
pp. 20-25 ◽  
Author(s):  
Robert J. Hargreaves ◽  
Eric Buzan ◽  
Michael Dulick ◽  
Peter F. Bernath
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Elevated Temperatures ◽  
Absorption Cross

scholarly journals New and improved infrared absorption cross sections for chlorodifluoromethane (HCFC-22)

2016 ◽  
Vol 9 (6) ◽  
pp. 2593-2601 ◽  
Author(s):  
Jeremy J. Harrison
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Infrared Absorption ◽  
Stratospheric Ozone ◽  
Optical Path Difference ◽  
Path Difference ◽  
Montreal Protocol ◽  
Absorption Cross ◽  
Atmospheric Conditions ◽  
The One

Abstract. The most widely used hydrochlorofluorocarbon (HCFC) commercially since the 1930s has been chloro-difluoromethane, or HCFC-22, which has the undesirable effect of depleting stratospheric ozone. As this molecule is currently being phased out under the Montreal Protocol, monitoring its concentration profiles using infrared sounders crucially requires accurate laboratory spectroscopic data. This work describes new high-resolution infrared absorption cross sections of chlorodifluoromethane over the spectral range 730–1380 cm−1, determined from spectra recorded using a high-resolution Fourier transform spectrometer (Bruker IFS 125HR) and a 26 cm pathlength cell. Spectra of chlorodifluoromethane/dry synthetic air mixtures were recorded at resolutions between 0.01 and 0.03 cm−1 (calculated as 0.9/MOPD; MOPD denotes the maximum optical path difference) over a range of temperatures and pressures (7.5–762 Torr and 191–295 K) appropriate for atmospheric conditions. This new cross-section dataset improves upon the one currently available in the HITRAN (HIgh-resolution TRANsmission) and GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques) databases; in particular it provides coverage over a wider range of pressures and temperatures, has more accurate wavenumber scales, more consistent integrated band intensities, improved signal-to-noise, is free of channel fringing, and additionally covers the ν2 and ν7 bands.

scholarly journals Alkaline exospheres of exoplanet systems: evaporative transmission spectra

2020 ◽  
Vol 497 (4) ◽  
pp. 5271-5291 ◽  
Author(s):  
Andrea Gebek ◽  
Apurva V Oza
Keyword(s):  
High Resolution ◽  
Cross Sections ◽  
Planetary Atmospheres ◽  
Hydrostatic Equilibrium ◽  
Transmission Spectra ◽  
Absorption Cross ◽  
Density Profiles ◽  
Hot Jupiters ◽  
Exoplanet Systems ◽  
Sodium And Potassium

ABSTRACT Hydrostatic equilibrium is an excellent approximation for the dense layers of planetary atmospheres, where it has been canonically used to interpret transmission spectra of exoplanets. Here, we exploit the ability of high-resolution spectrographs to probe tenuous layers of sodium and potassium gas due to their formidable absorption cross-sections. We present an atmosphere–exosphere degeneracy between optically thick and optically thin mediums, raising the question of whether hydrostatic equilibrium is appropriate for Na i lines observed at exoplanets. To this end we simulate three non-hydrostatic, evaporative, density profiles: (i) escaping, (ii) exomoon, and (iii) torus to examine their imprint on an alkaline exosphere in transmission. By analysing an evaporative curve of growth, we find that equivalent widths of $W_{\mathrm{Na D2}} \sim 1{\!-\!} 10\, \mathrm{m\mathring{\rm A}}$ are naturally driven by evaporation rates ∼103−105 kg s−1 of pure atomic Na. To break the degeneracy between atmospheric and exospheric absorption, we find that if the line ratio is D2/D1 ≳ 1.2 the gas is optically thin on average roughly indicating a non-hydrostatic structure of the atmosphere/exosphere. We show this is the case for Na i observations at hot Jupiters WASP-49b and HD189733b and also simulate their K i spectra. Lastly, motivated by the slew of metal detections at ultra-hot Jupiters, we suggest a toroidal atmosphere at WASP-76b and WASP-121b is consistent with the Na i data at present.

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