A&A 576, A59 (2015) Astronomy DOI: 10.1051/0004-6361/201425018 & c ESO 2015 Astrophysics Combining high-dispersion spectroscopy with high contrast imaging: Probing rocky planets around our nearest neighbors I. Snellen1,R.deKok1,2,J.L.Birkby1,3,,B.Brandl1, M. Brogi1,4,, C. Keller1, M. Kenworthy1, H. Schwarz1, and R. Stuik1 1 Leiden Observatory, Leiden University, Postbus 9513, 2300 RA Leiden, The Netherlands e-mail:
[email protected] 2 SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands 3 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 4 Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA Received 18 September 2014 / Accepted 20 January 2015 ABSTRACT Context. Ground-based high-dispersion (R ∼ 100 000) spectroscopy (HDS) is proving to be a powerful technique with which to characterize extrasolar planets. The planet signal is distilled from the bright starlight, combining ral and time-differential filtering techniques. In parallel, high-contrast imaging (HCI) is developing rapidly, aimed at spatially separating the planet from the star. While HDS is limited by the overwhelming noise from the host star, HCI is limited by residual quasi-static speckles. Both techniques currently reach planet-star contrast limits down to ∼10−5, albeit for very different types of planetary systems. Aims. In this work, we discuss a way to combine HDS and HCI (HDS+HCI). For a planet located at a resolvable angular distance from its host star, the starlight can be reduced up to several orders of magnitude using adaptive optics and/or coronography.