CLOUD BASE SIGNATURE IN TRANSMISSION SPECTRA OF EXOPLANET ATMOSPHERES

Journal Article · Tue Jul 01 00:00:00 EDT 2014 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/789/1/L11· OSTI ID:22365749

Vahidinia, Sanaz ^[1]; Cuzzi, Jeffrey N.; Marley, Mark ^[2]; Fortney, Jonathan ^[3]

---

1. Bay Area Environmental Research Institute, NASA Ames Research Center, Moffett Field, CA (United States)
2. Space Science Division, Ames Research Center, Moffett Field, CA (United States)
3. Astronomy Department, University of California, Santa Cruz, CA (United States)

We present an analytical model for the transmission spectrum of a transiting exoplanet, showing that a cloud base can produce an observable inflection point in the spectrum. The wavelength and magnitude of the inflection can be used to break the degeneracy between the atmospheric pressure and the abundance of the main cloud material, however, the abundance still depends on cloud particle size. An observed inflection also provides a specific point on the atmospheric P-T profile, giving us a ''thermometer'' to directly validate or rule out postulated cloud species. We apply the model to the transit spectrum of HD 189733b.

• OSTI ID: 22365749
• Journal Information: Astrophysical Journal Letters, Vol. 789, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ABSORPTION SPECTRA
ABUNDANCE
ATMOSPHERIC PRESSURE
CLOUDS
PARTICLE SIZE
PLANETARY ATMOSPHERES
PLANETS
RADIANT HEAT TRANSFER
SATELLITE ATMOSPHERES
SCATTERING
WAVELENGTHS