Hydrogen- and Helium-Broadening of Phosphine Lines

Lévy, A.; Lacome, N.; Tarrago, G.

doi:10.1006/jmsp.1993.1014

Cited by 40 publications

(26 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…comm.). The PH 3 lines were broadened by both H 2 and He using γ H 2 = 0.1078−0.0014J cm −1 atm −1 and γ He = 0.0618−0.0012J cm −1 atm −1 (Levy et al 1993), and a temperature dependence of T n where n = 0.702−0.01J (J is the rotational quantum number). For NH 3 we use line data from Kleiner et al (2003), hydrogen-and helium-broadened using the empirical model of Brown & Peterson (1994).…”

Section: Saturn Continuum Modelling: Temperatures Ph 3 and Nhmentioning

confidence: 99%

Sub-millimetre spectroscopy of Saturn’s trace gases fromHerschel/SPIRE

Fletcher

Swinyard

Salji

et al. 2012

A&A

View full text Add to dashboard Cite

Aims. We provide an extensive new sub-millimetre survey of the trace gas composition of Saturn's atmosphere using the broad spectral range (15-51 cm −1 ) and high spectral resolution (0.048 cm −1 ) offered by Fourier transform spectroscopy by the Herschel/SPIRE instrument (Spectral and Photometric Imaging REceiver). Observations were acquired in June 2010, shortly after equinox, with negligible contribution from Saturn's ring emission. Methods. Tropospheric temperatures and the vertical distributions of phosphine and ammonia are derived using an optimal estimation retrieval algorithm to reproduce the sub-millimetre data. The abundance of methane, water and upper limits on a range of different species are estimated using a line-by-line forward model. Results. Saturn's disc-averaged temperature profile is found to be quasi-isothermal between 60 and 300 mbar, with uncertainties of 7 K due to the absolute calibration of SPIRE. Modelling of PH 3 rotational lines confirms the vertical profile derived in previous studies and shows that negligible PH 3 is present above the 10-to 20-mbar level. The upper tropospheric abundance of NH 3 appears to follow a vapour pressure distribution throughout the region of sensitivity in the SPIRE data, but the degree of saturation is highly uncertain. The tropospheric CH 4 abundance and Saturn's bulk C/H ratio are consistent with Cassini studies. We improve the upper limits on several species (H 2 S, HCN, HCP and HI); provide the first observational constraints on others (SO 2 , CS, methanol, formaldehyde, CH 3 Cl); and confirm previous upper limits on HF, HCl and HBr. Stratospheric emission from H 2 O is suggested at 36.6 and 38.8 cm −1 with a 1σ significance level, and these lines are used to derive mole fractions and column abundances consistent with ISO and SWAS estimations a decade earlier.

show abstract

Section: Saturn Continuum Modelling: Temperatures Ph 3 and Nhmentioning

confidence: 99%

Sub-millimetre spectroscopy of Saturn’s trace gases fromHerschel/SPIRE

Fletcher

Swinyard

Salji

et al. 2012

A&A

View full text Add to dashboard Cite

show abstract

“…For CO, we adopted the values measured by Bouanich and Brodbeck (1973) and . For NH 3 , PH 3 , and CH 3 D, we used the empirical expressions given in Brown and Peterson (1994), Lévy et al (1993Lévy et al ( , 1994, and Boussin (1999) respectively. For GeH 4 , we retained the linewidth and temperature exponent measured for two lines by .…”

Section: Radiative Transfer Modelingmentioning

confidence: 99%

Carbon Monoxide on Jupiter: Evidence for Both Internal and External Sources

Bézard¹,

Lellouch²,

Strobel³

et al. 2002

Icarus

132

229

View full text Add to dashboard Cite

“…The shape of the rotational NH 3 lines broadened by H 2 was modeled using the line coupling derived by Birnbaum et al (2000). The pressure-broadened line widths for PH 3 broadened by H 2 and He were taken from a general formula given by Levy et al (1993), their temperature dependence was taken from Levy et al (1994), and Van Vleck-Weiskoff lineshapes were assumed.…”

Section: Model Basismentioning

confidence: 99%