Cool Stars 14 - Submitted Abstract # 113
This version created on 05 October 2006

Determining eta_Earth:  the case for late M-dwarfs


Michael Endl, McDonald Observatory
Martin Kuerster,  Max-Planck-Institut fuer Astronomie Heidelberg

The parameter eta_Earth, the frequency of extrasolar planets with
masses similar to Earth, is one of the most crucial parameters for the
design and overall costs of a TPF/Darwin-type mission.  At the moment
the value of eta_Earth is completely unknown.  We discuss the
feasibility of searching for extremely low-mass planets orbiting late
M-dwarf stars using the currently available method of high-precision
radial velocity (RV) measurements.  For these low luminosity stars the
classical habitable zone is also located very close to the star,
precisely where the RV technique is most sensitive.  We describe our
program at the ESO VLT and its UVES spectrograph to search for
terrestrial planets in short-period orbits around a sample of southern
M dwarfs.  For the targets Barnard's star and Proxima Cen we
demonstrate our current detection sensitivity for extremely low-mass
(terrestrial) planets.

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