2008/06/02 by J. R. Barnes, Travis S. Barman, H. R. A. Jones +4 · 17 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Deconvolution #Ephemeris #Exoplanet #Giant planet #Infrared #Planet #Scientific Research and Discoveries #Spectral line #Spectrograph #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2008.13831.x
published in Monthly Notices of the Royal Astronomical Society 390(3), 1258-1266 (Oxford University Press) · 9 pages
arxiv created 2008/06/02 · openalex publication_date 2008/10/03 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We have carried out a search for the 2.14-μm spectroscopic signature of the close orbiting extrasolar giant planet, HD 179949b. High-cadence time-series spectra were obtained with the Cryogenic high-resolution InfraRed Échelle Spectrograph at Very Large Telescope, Unit 1 on two closely separated nights. Deconvolution yielded spectroscopic profiles with mean signal-to-noise ratios of several thousand, enabling the near-infrared contrast ratios predicted for the HD 179949 system to be achieved. Recent models have predicted that the hottest planets may exhibit spectral signatures in emission due to the presence of TiO and VO which may be responsible for a temperature inversion high in the atmosphere. We have used our phase-dependent orbital model and tomographic techniques to search for the planetary signature under the assumption of an absorption line dominated atmospheric spectrum, where T and V are depleted from the atmospheric model, and an emission line dominated spectrum, where TiO and VO are present. We do not detect a planet in either case, but the 2.120–2.174-μm wavelength region covered by our observations enables the deepest near-infrared limits yet to be placed on the planet/star contrast ratio of any close orbiting extrasolar giant planet system. We are able to rule out the presence of an atmosphere dominated by absorption opacities in the case of HD 179949b at a contrast ratio of Fp/F*∼ 1/3350, with 99 per cent confidence.