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

and accretion disks with heavy numerical MHD simulations; and relativistic plasma physics: reconnections,
shocks and flows (for Blazars, micro-quasars and Gamma Ray Bursts).
Some branch activities will continue in parallel: accretion-ejection phenomena in young stellar objects
(numerical simulations of the interaction between the stellar magnetosphere and the accretion disk);
astrocladistics (innovative classification method of galaxies in relation with the issue of AGN formation
by merging). Also, the team will continue developing connections with High Energy Experiments (XMM,
INTEGRAL, GLAST, SIMBOL-X, HESS etc.) and with the LAOG observing facilities (VITRUV, ...).
Over the longer term (2015), the Sherpas team expects to be involved in the theory of transitory signals
from Black Hole environments that will be recorded simultaneously by different kinds of astroparticle
experiments, revealing different but correlated aspects of their phenomenology. This will involve gammaray
transient emissions, neutrino bursts and gravitational waves. The main sources of such combined
events will be the double quasars. The Pierre Auger Observatory for UHE cosmic rays will also be an
important source of informations for AGNs and GRBs physics, as well as for the knowledge of the cosmic
magnetic field.
• Instrumental developments: towards higher angular resolution and higher dynamic range.
The instrumental activities for the present period have been dominated by the delivery of two major
NIR (JHK) instruments for ESO’s VLT: the large adaptive optics system NAOS, and the interferometric
recombiner AMBER, as well as the WIRCAM wide-field NIR camera for CFHT. While these instruments
are already successfully working, they show that the present goals of LAOG cannot be fully obtained
with them: if one wants to really understand the formation of planetary systems, one needs to reach a
linear resolution of 1 AU or less at 150 pc (the typical distance of low-mass star forming regions), which
translates in a 6 mas spatial resolution; if one wants to image planets close to their host star, i.e., within
the first diffraction minimum, a tremendous dynamic range is required (∼ 10 −6 ).
To face these challenges, LAOG has embarked in two major projects for ESO’s 2nd generation of VLT
instruments, which will draw the majority of its engineering manpower (15 FTE) for the period 2007-2010:
• (i) The VLT-PF (“Planet Finder”) project, which is now in the final stages of approval. LAOG
led a European consortium which was selected by ESO in 2005 over a competing one. Compared to NAOS,
the main emphasis is on a very high dynamic range (∼ 3 × 10 5 at 1 Airy radius, or at ∼ 20 mas at 1 µm for
an 8-m telescope), to reach the scientific goal of direct detection of dozens of Jupiter-mass planets, possibly in
multiple systems (as a few are already known from the radial-velocity method). It is expected to be completed
in 2009-2010. This will pave the way to future spectroscopy of these planets, and eventually of Earth-like planets
(Darwin project, post-2015, see below).
• (ii) The VITRUV project. Proposed to ESO which may reach a decision in 2006, this is currently
an in-house LAOG project for the 2nd generation VLTI. It basically consists in a large interferometric beam
recombiner making use of integrated optics. Its ultimate goal is to use all 8 Paranal telescopes (4 UT and 4 AT)
to make up one of the world’s largest optical/IR interferometer, with a maximum baseline of 200 m. This will
allow to reach the maximum possible angular resolution of ∼ 0.5 mas in the visible range, allowing for instance
to probe the inner regions and fine structure of circumstellar disks of young stars and AGNs and their jets, i.e.,
to probe in unprecedented detail the “central engine” of the accretion-ejection phenomenon in a wide diversity
of environments.
Therefore, the main challenge for LAOG resources will be to manage two important projects (if VITRUV
is approved) over the same time frame, while continuing R&D activities. Details about other projects under
consideration can be found in the GRIL chapter.
To help in the interpretation of increasingly complex observations, LAOG is also investing significant efforts
to contribute to the Virtual Observatory (VO). In its present stage, the VO offers an easy and interoperable
access to the astrophysical data (spectra, images, etc) gathered by the major observatories all over the world
and to the corresponding publications and tables. This huge work is the fruit of an unprecedented international
collaboration, through a hierarchy of working groups and institutions – with special mention in France to the
CDS in Strasbourg and to the recent “Action Spécifique Observatoire Virtuel” of INSU. Our objective is to
enrich the VO with original services. Most tools developed at the JMMC (as already done for SearchCalib)
will be interwoven to the VO for an optimal preparation and calibration of observations. Also, theoretical
developments will be offered to the VO. Inelastic collisional rates computed in the ASTROMOL team (including
the corresponding milestones for the “Molecular Universe” RTN framework) will be included in the advanced
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