PROBING THE TERMINATOR REGION ATMOSPHERE OF THE HOT-JUPITER XO-1b WITH TRANSMISSION SPECTROSCOPY

Journal Article · Thu Apr 01 00:00:00 EDT 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/712/2/L139; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21305065

Tinetti, G ^[1]; Deroo, P; Swain, M R; Vasisht, G; Brown, L R ^[2]; Griffith, C A ^[3]; Burke, C ^[4]

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1. University College London, Department of Physics and Astronomy, Gower Street, London WC1E 6BT (United Kingdom)
2. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
3. University of Arizona, Lunar and Planetary Laboratory, 1629 E. University Boulevard, Tucson, AZ 85721 (United States)
4. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-65, Cambridge, MA 02138 (United States)

We report here the first infrared spectrum of the hot-Jupiter XO-1b. The observations were obtained with the NICMOS instrument on board the Hubble Space Telescope during a primary eclipse of the XO-1 system. Near photon-noise-limited spectroscopy between 1.2 and 1.8 {mu}m allows us to determine the main composition of this hot-Jupiter's planetary atmosphere with good precision. This is the third hot-Jupiter's atmosphere for which spectroscopic data are available in the near-IR. The spectrum shows the presence of water vapor (H{sub 2}O), methane (CH{sub 4}), and carbon dioxide (CO{sub 2}), and suggests the possible presence of carbon monoxide (CO). We show that the published IRAC secondary transit emission photometric data are compatible with the atmospheric composition at the terminator determined from the NICMOS spectrum, with a range of possible mixing ratios and thermal profiles; additional emission spectroscopy data are needed to reduce the degeneracy of the possible solutions. Finally, we note the similarity between the 1.2-1.8 {mu}m transmission spectra of XO-1b and HD 209458b, suggesting that in addition to having similar stellar/orbital and planetary parameters the two systems may also have a similar exoplanetary atmospheric composition.

• OSTI ID: 21305065
• Journal Information: Astrophysical Journal Letters, Vol. 712, Issue 2; Other Information: DOI: 10.1088/2041-8205/712/2/L139; 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
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
CARBON DIOXIDE
CARBON MONOXIDE
ECLIPSE
EMISSION SPECTROSCOPY
INFRARED SPECTRA
JUPITER PLANET
METHANE
MIXING RATIO
PHOTONS
PLANETARY ATMOSPHERES
TELESCOPES
WATER
WATER VAPOR