CDSD-1000, the high-temperature carbon dioxide spectroscopic databank

Tashkun, S.A.; Perevalov, V.I.; Teffo, J.-L.; Быков, А. Д.; Lavrentieva, N. N.

doi:10.1016/s0022-4073(03)00152-3

Cited by 243 publications

(164 citation statements)

References 138 publications

Supporting

Mentioning

161

Contrasting

Order By: Relevance

“…in Griffith et al [21], line-by-line calculations of the HITEMP line parameters [37] are used to calculate k-coefficients of CO. For CH 4 and H 2 O, k-coefficients were calculated from the absorption coefficients derived by Freedman et al [38]; absorption by CO 2 lines derive from lineby-line calculations of the CDSD database [39]. However, for CH 4 , at wavelengths below 3 µm, we increase the methane absorption by a factor of 10 to fit the laboratory data at 2.2 and 1.7 µm [40,41].…”

Section: (A) Secondary Eclipse Measurementsmentioning

confidence: 99%

Disentangling degenerate solutions from primary transit and secondary eclipse spectroscopy of exoplanets

Griffith

2014

Phil. Trans. R. Soc. A.

View full text Add to dashboard Cite

Infrared transmission and emission spectroscopy of exoplanets, recorded from primary transit and secondary eclipse measurements, indicate the presence of the most abundant carbon and oxygen molecular species (H 2 O, CH 4 , CO and CO 2 ) in a few exoplanets. However, efforts to constrain the molecular abundances to within several orders of magnitude are thwarted by the broad range of degenerate solutions that fit the data. Here, we explore, with radiative transfer models and analytical approximations, the nature of the degenerate solution sets resulting from the sparse measurements of ‘hot Jupiter’ exoplanets. As demonstrated with simple analytical expressions, primary transit measurements probe roughly four atmospheric scale heights at each wavelength band. Derived mixing ratios from these data are highly sensitive to errors in the radius of the planet at a reference pressure. For example, an uncertainty of 1% in the radius of a 1000 K and H 2 -based exoplanet with Jupiter's radius and mass causes an uncertainty of a factor of approximately 100–10 000 in the derived gas mixing ratios. The degree of sensitivity depends on how the line strength increases with the optical depth (i.e. the curve of growth) and the atmospheric scale height. Temperature degeneracies in the solutions of the primary transit data, which manifest their effects through the scale height and absorption coefficients, are smaller. We argue that these challenges can be partially surmounted by a combination of selected wavelength sampling of optical and infrared measurements and, when possible, the joint analysis of transit and secondary eclipse data of exoplanets. However, additional work is needed to constrain other effects, such as those owing to planetary clouds and star spots. Given the current range of open questions in the field, both observations and theory, there is a need for detailed measurements with space-based large mirror platforms (e.g. James web space telescope) and smaller broad survey telescopes as well as ground-based efforts.

show abstract

Section: (A) Secondary Eclipse Measurementsmentioning

confidence: 99%

Disentangling degenerate solutions from primary transit and secondary eclipse spectroscopy of exoplanets

Griffith

2014

Phil. Trans. R. Soc. A.

View full text Add to dashboard Cite

show abstract

“…NEMESIS was developed by Irwin et al (2008) for atmospheric retrieval of solar system planets, and it has since been extended to enable the same analysis for observations of transiting and directly imaged extrasolar planets CDSD-1000 (Tashkun et al 2003) CO HITRAN1995 (Rothman et al 1995) CH 4 STDS (Wenger & Champion 1998) Na VALD (Heiter et al 2008) K VALD (Heiter et al 2008) (Lee et al 2012Barstow et al 2013a). NEMESIS is an Optimal Estimation retrieval model (Rodgers 2000) and uses a correlated-k radiative transfer model (Lacis & Oinas 1991;Goody & Yung 1989).…”

Section: Nemesismentioning

confidence: 99%

CLOUDS ON THE HOT JUPITER HD189733b: CONSTRAINTS FROM THE REFLECTION SPECTRUM

Barstow

Aigrain

Irwin

et al. 2014

ApJ

View full text Add to dashboard Cite

The hot Jupiter HD 189733b is probably the best studied of the known extrasolar planets, with published transit and eclipse spectra covering the near UV to mid-IR range. Recent work on the transmission spectrum has shown clear evidence for the presence of clouds in its atmosphere, which significantly increases the model atmosphere parameter space that must be explored in order to fully characterize this planet. In this work, we apply the NEMESIS atmospheric retrieval code to the recently published HST/STIS reflection spectrum, and also to the dayside thermal emission spectrum in light of new Spitzer/IRAC measurements, as well as our own re-analysis of the HST/NICMOS data. We first use the STIS data to place some constraints on the nature of clouds on HD 189733b and explore solution degeneracy between different cloud properties and the abundance of Na in the atmosphere; as already noted in previous work, absorption due to Na plays a significant role in determining the shape of the reflection spectrum. We then perform a new retrieval of the temperature profile and abundances of H 2 O, CO 2 , CO, and CH 4 from the dayside thermal emission spectrum. Finally, we investigate the effect of including cloud in the model on this retrieval process. We find that the current quality of data does not warrant the extra complexity introduced by including cloud in the model; however, future data are likely to be of sufficient resolution and signal-to-noise that a more complete model, including scattering particles, will be required.

show abstract

“…The HITRAN and HI-TEMP databases were discussed in detail in the literature [44,45]. Based on these databases, CDSD (only for CO 2 ) was developed by Tashkun et al [37][38][39][40]. CDSD-1000 (updated) [40] is an updated version and is used in this study.…”

Section: Databasesmentioning

confidence: 99%

“…Prior to the availability of HITEMP2010, earlier versions of LBL databases, such as HITEMP1995, HITRAN2004, and HITRAN2008, had been employed for LBL calculations. The CDSD database [37][38][39][40], which is more accurate for CO 2 , also was included in the present evaluation study.…”

Section: Introductionmentioning

confidence: 99%