Untitled - Laboratoire d'Astrophysique de l'Observatoire de Grenoble

Chapter 6
Introduction of the team & Science
Results
6.1 FOST: a large research group on the formation of Stars and
Planets, and the Lower Mass Function
Since the last review committee visited LAOG, three groups joined efforts to form what is now known as team
FOST. FOST is an acronym standing for “FOrmation Stellaire, objets SubStellaires, and Systèmes planéTaires”,
that is often contracted to “Star and Planet Formation” for practical purposes.
FOST is currently the largest of four teams at LAOG. It houses 20 staff members (including one on leave at
CFHT), 3 post-docs, and 14 PhD students (in full or shared supervision). FOST evolves quickly. Since 2001,
four permanent positions were allocated to our team: Gaspard Duchêne (CNAP), Nicolas Grosso (CNRS),
Jean-Charles Augereau (CNAP), and Estelle Moraux (MdC-UJF). 5 post-docs visited us: David James (now
a post-doc at Alabama State University), Tim Kendall (now assistant professor at University of Hertfordshire,
UK), and Hideki Ozawa (now postdoc at Osaka University, Japan). Sylvia Alencar (Brazil) and Willem-Jan de
Wit (Holland) are the current FOST post-docs. At the time of writing, Claudio Zanni is about to join us in the
framework of JETSET. 7 PhD dissertations were defended successfully since 2001.
The spectrum of FOST’s activities is broad. It spans the study of solar-like young stars and their environments
(disks and jets) as well as the study of lower mass brown dwarfs and free-floating “planets” in nearby star
forming regions. It also covers the study of the more evolved so-called “debris disks” now found around stars
of all masses, from A to M, and a census of the low-mass population of the Solar neighbourhood including, in
particular, multiplicity and the search for extrasolar planets by radial velocity. All these efforts have a common
long term goal: Our Origins, identify and understand the mechanisms by which stars and planets form and
evolve.
In the following sections, our main activities are described. The presentation aims at highlighting not all,
but some important results obtained by FOST members recently. Hopefully, the presentation will also clearly
show that within FOST, the activities are now tightly the various intertwined and the boundaries between the
former groups that merged to form FOST are vanishing quickly, both in terms of scientific goals and in terms
of human resources. This is felt as a success by all of us. This feeling is further strengthened by the superb
(and still growing) synergy between FOST and all other teams at LAOG: with SHERPAS for the star-disk
interaction and jets physics; with ASTROMOL for the coupling of dust and gas studies in protoplanetary disks,
and with GRIL for providing some of the key instruments to reach our science goals.
6.2 Scientific Highlights
• Direct images of planetary mass companions around 2 objects in young nearby associations (2MASSW J120733
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