Workshop : Simulations
of magnetohydrodynamic turbulence in astrophysics:
recent achievements and perspectives
Paris, France, 2 - 6 July
2001
Objective:
Numerical simulations are a powerful tool for the investigation of
the complex physics of star formation and more generally of the interstellar
matter. Magnetic field is ubiquitous in this medium and the motions are
turbulent and supersonic. A huge number of degrees of freedom are coupled
over several orders of magnitude in length scales, from the size of the
super-clouds in the Galaxy (
cm)
to that of protostellar cores (
cm)
and, likely even further, to the dissipative scales of the magneto-hydrodynamic
(MHD) turbulence. Several teams worldwide have numerically addressed the
properties of interstellar MHD turbulence, concentrating on either some
aspects of the physics or on subranges of all the coupled scales. The first
objective of this workshop will be a presentation and confrontation of
the existing results and their points of agreement, with an emphasis on
the open issues. In particular, the nature, origin and role of the coherent
structures of the magnetic field which form in MHD turbulence (sheets,
tubes, fibrillation of the field) is still not understood. In this regard,
it can be of great interest to benefit from the expertise of researchers
in the fields of solar convective turbulence as well as solar dynamo, topics
where recent advances have been achieved. The second objective of this
workshop will be a discussion of the next generation of numerical codes
to be developed. Indeed, the present ones often use techniques that, for
several reasons, will rapidly become insufficient for capturing both the
multi-scale dynamics and the variety of discontinuities induced by shocks
or thermal instabilities. The existence of localized regions of strong
gradients is a situation where adaptive mesh refinement (AMR) techniques
become essential. The development of such codes, which have also to be
parallelized, requires the skills of specialized numericists. Some versions
(MHD, 3D, AMR) already exist, have been made available to the community
and have already brought results. We propose to have these codes and their
capabilities presented to the astrophysical community in the perspective
of adapting them to the complexity of the physics of interstellar turbulence.
Scientific organizing committee :
A. Brandenburg (Nordita, Copenhagen, Denmark),
E. Falgarone (Ecole Normale Supérieure & Observatoire de
Paris, Paris, France) co-chair person,
C. Heiles (U.C. Berkeley, USA),
T. Passot (Observatoire de la Côte d'Azur, Nice, France) co-chair
person,
Y. Ponty (Observatoire de la Côte d'Azur, Nice, France),
M. Proctor (DAMTP, Cambridge, UK),
A. Raga (UNAM, Mexico, Mexico),
M. Tagger (CEA, Saclay, France),
E. Vázquez-Semadeni (UNAM, Morelia, Mexico),
J.P. Zahn (Observatoire de Paris, Meudon, France),
E. Zweibel (U. Colorado, Boulder, USA).
Local organizing committee:
Marie Francoise Ducos
Edith Falgarone
Thierry Passot
Michel Perault
Annie Touchant
Main topics to be covered:
Numerical simulations of interstellar turbulence
Turbulent convection
Algorithms for high resolution simulations of MHD flows
Small-scale structures in MHD turbulence
Solar and galactic dynamos
Radiative shocks
Observational constraints on interstellar and solar turbulence and
magnetic fields
Limits of the MHD approximation in the context of ISM turbulence
Lectures:
Both plenary lectures (40' +10'
for
questions) and contributed papers ( 15'+ 5' for questions)
are planned.
Posters will be on permanent display.
The invited lecturers are :
S. Balbus (U. Virginia, USA), A. Bhattacharjee (U. Iowa,
USA), A. Brandenburg (Nordic Institute for Theoretical Physics, Denmark),
D. Clarke (Saint Mary's University, Halifax, Canada and LAOG, Grenoble,
France),
R. Crutcher (NCSA, U. Illinois), R. Grauer (Institut fuer Theoretische
Physik, Duesseldorf, Germany),
C. McKee (U.C. Berkeley, USA), M. Mac Low (American Museum of Natural
History, New York, USA),
W. Matthaeus (U. Delaware, USA), A. Nordlund (Astronomical Observatory,
Copenhagen, Denmark),
E. Ostriker (U. Maryland, USA), E. Vishniac (Johns Hopkins University,
USA),
R. Walder (Institut fuer Astronomie, Zurich, Switzerland), U. Ziegler
(Astrophysikalisches Institut Potsdam, Germany),
E. Zweibel (U. Colorado, Boulder, USA)
Registration:
To register to this workshop, please fill in the enclosed registration
form by clicking
here .
Contributed papers:
If you wish to submit a contributed paper, please send by email to
passot@obs-nice.fr,
no later than April 30th, 2001, an abstract in regular latex,
not exceeding one printed page, and possibly including references.
Requests for financial support:
Young scientist support, intended for PhD students or recent PhD, will
cover registration fees and part of accomodation.
Application for support must include a recommendation letter and a
curriculum vitae. The deadline for financial support requests is March
30th.
Practical
informations
Lodging
List
of Participants
List
of Abstracts
Scientific
Program
The
proceedings are now published in Springer Verlag
Organizers:
Edith Falgarone (edith@lra.ens.fr)
and Thierry Passot (passot@obs-nice.fr)
Laboratoire de Radioastronomie,
Laboratoire Cassini
ENS - Departement de Physique,
Observatoire de la Côte d'Azur
24 rue Lhomond 75231 Paris Cedex 05, BP
4229, 06304 Nice Cedex 4
Acknowledgments :
Programme National PCMI
GdR Turbulence
Laboratoire de Radioastronomie, ENS
Observatoire de Paris