EDP Sciences Journals List
Advanced Search
Subscriber Authentication Point
Home All issues Volume 489/3 Article
Free access article

Issue A&A
Volume 489, Number 3, October III 2008
Page(s) 1345 - 1354
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361:200810090
Published online 18 August 2008



A&A 489, 1345-1354 (2008)
DOI: 10.1051/0004-6361:200810090

Exoplanet characterization with long slit spectroscopy

A. Vigan, M. Langlois, C. Moutou, and K. Dohlen

Laboratoire d'Astrophysique de Marseille, Technopôle Marseille Étoile, 38 rue Frédéric Joliot Curie, 13013 Marseille, France
    e-mail: arthur.vigan@oamp.fr

Received 29 April 2008 / Accepted 22 July 2008

Abstract
Context. Extrasolar planets observation and characterization by high contrast imaging instruments is set to be a very important subject in observational astronomy. Dedicated instruments are being developed to achieve this goal with very high efficiency. In particular, full spectroscopic characterization of low temperature planetary companions is an extremely important milestone.
Aims. We present a new data analysis method for long slit spectroscopy (LSS) with coronagraphy, which allows characterization of planetary companions of low effective temperature. In a speckle-limited regime, this method allows an accurate estimation and subtraction of the scattered starlight, to extract a clean spectrum of the planetary companion.
Methods. We performed intensive LSS simulations with IDL/CAOS to obtain realistic spectra of low (R = 35) and medium (R = 400) resolution in the J, H, and K bands. The simulated spectra were used to test our method and estimate its performance in terms of contrast reduction and extracted spectra quality. Our simulations are based on a software package dedicated to the development of SPHERE, a second generation instrument for the ESO-VLT.
Results. Our method allows a contrast reduction of 0.5 to 2.0 mag compared to the coronagraphic observations. For M0 and G0 stars located at 10 pc, we show that it would lead to the characterization of companions with $T_{\rm e\! f\! f}$ of 600 K and 900 K respectively, at angular separations of 1.0´´. We also show that errors in the wavelength calibration can produce significant errors in the characterization, and must therefore be minimized as much as possible.


Key words: techniques: spectroscopic -- techniques: image processing -- methods: data analysis -- stars: planetary systems



© ESO 2008


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.