Skip navigation
  • INAF logo
  • Home
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects
  • Explore by
    • Research outputs
    • Researchers
    • Organization units
    • Projects
  • Login:
    • My DSpace
    • Receive email
      updates
    • Edit Account details
  • Italian
  • English

  1. OA@INAF
  2. PRODOTTI RICERCA INAF
  3. 1 CONTRIBUTI IN RIVISTE (Journal articles)
  4. 1.01 Articoli in rivista
Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12386/28910
Title: Exoplanet atmospheres with GIANO. II. Detection of molecular absorption in the dayside spectrum of HD 102195b
Authors: Guilluy, G.
SOZZETTI, Alessandro 
Brogi, M.
BONOMO, ALDO STEFANO 
GIACOBBE, Paolo 
CLAUDI, Riccardo 
BENATTI, SERENA 
Issue Date: 2019
Journal: ASTRONOMY & ASTROPHYSICS 
Number: 625
First Page: A107
Abstract: Context. The study of exoplanetary atmospheres is key to understanding the differences between their physical, chemical, and dynamical processes. Until now, the bulk of atmospheric characterization analyses have been conducted on transiting planets. On a number of sufficiently bright targets, high-resolution spectroscopy (HRS) has also been successfully tested for nontransiting planets mainly by using spectrographs mounted on 8 and 10 m class ground-based telescopes. <BR /> Aims: The aim of this analysis is to study the dayside of the nontransiting planet HD 102195b using the GIANO spectrograph mounted at the Telescopio Nazionale Galileo (TNG), and thereby demonstrate the feasibility of atmospheric characterization measurements. In particular, we wish to demonstrate the possibility of molecular detection with the HRS technique for nontransiting planets using 4 m class telescopes. <BR /> Methods: Our data-analysis technique exploits the fact that the Doppler-shifted planetary signal changes on the order of many kilometers per second during the observations, in contrast with the telluric absorption which is stationary in wavelength. This allows us to effectively remove the contamination from telluric lines in the GIANO spectra while preserving the features of the planetary spectrum. The emission signal from the atmosphere of HD 102195b is then extracted by cross-correlating the residual GIANO spectra with models of the planetary atmosphere. <BR /> Results: We detect molecular absorption from water vapor at the 4.4σ level of statistical significance. We also find convincing evidence for the presence of methane, which is detected at the 4.1σ level. This is the first detection of methane obtained with the HRS technique. The two molecules are detected with a combined significance of 5.3σ, at a semi-amplitude of the planet radial velocity K<SUB>P</SUB> = 128 ± 6 km s<SUP>-1</SUP>. We estimate a true planet mass of M<SUB>P</SUB> = 0.46 ± 0.03 M<SUB>J</SUB> and constrain the orbital inclination in the range 72.5° < i < 84.79° (1σ). Our analysis indicates a noninverted atmosphere for HD 102195b. This is expected given the relatively low temperature of the planet, inefficient to keep TiO/VO in gas phase. Moreover, a comparison with theoretical model expectations corroborates our detection of methane, and a cursory confrontation with chemical model predictions published in the literature suggests that the detected methane and water signatures could be consistent with a low C/O ratio for HD 102195b. Finally, as HD 102195 is one to three magnitudes fainter in the K-band than the nontransiting systems studied until now with 8 m telescopes, our study opens up the possibility for atmospheric characterization of a larger sample of exoplanets.
URI: http://hdl.handle.net/20.500.12386/28910
URL: https://www.aanda.org/articles/aa/full_html/2019/05/aa34615-18/aa34615-18.html
ISSN: 0004-6361
DOI: 10.1051/0004-6361/201834615
Bibcode ADS: 2019A&A...625A.107G
Fulltext: open
Appears in Collections:1.01 Articoli in rivista

Files in This Item:
File Description SizeFormat 
Guilluyetal.2019.pdfPdf editoriale2.15 MBAdobe PDFView/Open
Show full item record

Page view(s)

4
checked on Jan 16, 2021

Download(s)

2
checked on Jan 16, 2021

Google ScholarTM

Check

Altmetric


Items in DSpace are published in Open Access, unless otherwise indicated.


Explore by
  • Communities
    & Collections
  • Research outputs
  • Researchers
  • Organization units
  • Projects

Informazioni e guide per autori

https://openaccess-info.inaf.it: tutte le informazioni sull'accesso aperto in INAF

Come si inserisce un prodotto: le guide a OA@INAF

La Policy INAF sull'accesso aperto

Documenti e modelli scaricabili

Feedback
Built with DSpace-CRIS - Extension maintained and optimized by Logo 4SCIENCE