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

heart attack. Manuel went back to this topic after his well-known work on pre-main sequence (PMS) stellar
evolution. This challenge was all the more formidable that, contrary to PMS stars which draw their energy
only from gravitation, the late stages of stellar evolution involve a highly complex network of nuclear reactions.
His main legacy is the Starevol code, which is publicly available on the web and is now widely used by the
stellar evolution community worldwide. In addition to his time-consuming high-level responsibilities at UJF,
Manuel was a whole scientific team in himself, although he was on his way to build a real one with a PhD
student (see Siess and Leclair 2005); when he passed away, however, there was no one to continue this activity
at LAOG. (Fortunately, the field is continuing, chiefly under Manuel’s former PhD student Lionel Siess, now a
Professor in Marcel Arnould’s group in Brussels.) The proceedings of an international scientific colloquium held
at LAOG in 2004 “Stars and Nuclei: a Tribute to Manuel Forestini” is in preparation (EDP Sciences, edited by
T. Montmerle and C. Kahane).
Ancient Astronomy
One must also mention the work of C. Nozières on History of ancient Astronomy (Michel-Nozières 2002). She
is studying in the original Assyrian language, old astronomical texts on the measurement of the variation of
lunar visibility through the year.
1.1.3 A brief overview of the scientific teams of LAOG
We here give a brief “identity card” of each team. The following parts of this report (III to VI) will be devoted
to a much more detailed, individual account of their recent activities and prospective.
• The first axis (Origins: low-mass star formation and early evolution, and the path to planet formation),
is shared by all four teams. In alphabetical order:
(i) the “Astromol” (= molecular astrophysics) team mainly studies the physico-chemistry of the
earliest stages of star formation (molecular clouds, prestellar cores, protostars, and also young disks and
molecular outflows; timescale ∼ 10 5 − 10 6 yrs), but also includes fundamental astrochemistry (reaction
rates, transition probabilities, etc.).
Permanent staff: 10. PhDs completed: 2; underway: 2. Team leader: C. Ceccarelli (Astronomer).
(ii) the “FOST” (= star and planet formation, brown dwarfs) team focuses on later stages of
star formation, mainly the physics of star-disk interactions, evolved disks and the conditions for planet
formation (structural features like gaps and rings, dust grain evolution in disks, etc.; timescale ∼ 10 6 −10 7
yrs), and also on the formation mechanisms of binaries and the “Initial Mas Function” (IMF). A specific
activity within the team is the study of brown dwarfs, both as astronomical objects by themselves, and as
intermediate bodies between low-mass stars and exoplanets. The search and characterization of exoplanets
are themselves an increasing part of the FOST activities. The team contributes a lot to observations made
with LAOG-built instruments and to their interpretation.
Permanent staff: 13 + 7 shared with GRIL. PhDs completed: 5 + 1 with GRIL; underway:
9 + 3 with GRIL + 1 with Sherpas. Team leader: F. Ménard (CNRS).
(iii) the “GRIL” (= instrumental research group at LAOG) team concentrates on strategic issues
in research & development (R&D) for future instruments and detectors. While the situation may evolve, so
far GRIL’s responsibility has been to contribute to the development of optical and near-IR instruments for
large ground-based telescopes (ESO, CFH) with the highest spatial resolution (for instance with the goal
to resolve the inner parts of protoplanetary disks, i.e., within 1 AU at 450 pc, say), by way of adaptive
optics and interferometry, and/or the highest dynamic range (adaptive optics to image exoplanets as
closely as possible from their host star).
Permanent staff: 9 (including 8 engineers) + 7 shared with FOST. 1 PhDs completed: 3 +
1 with FOST; underway: 8 + 3 with FOST. Team leader: C. Perrier (Astronomer).
(iv) the “Sherpas” (= “sources of high energies and relativistic physics in accretion-ejection
structures”, in full) team is essentially involved in MHD theory calculations, with particular emphasis on
the accretion-ejection phenomenon in astrophysics. Here it mainly applies models to star-disk interactions
and disk-driven jets, where magnetic fields, instead of gravitation, play a dominant role.
1 two engineers qualified to supervised PhDs (’HDR’ in french)
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