The first two weeks of the programme are dedicated to stellar dynamo
theory and observations, and the last two for solar magnetic
activity, dynamos and data assimilation methods.
We plan to have informal gatherings over coffee every day at 10:00 and 16:00.
For some of the days we shall schedule talks or formal discussions at 10:30.
We are also organising a special workshop during the 5th-6th of
October in the honor of the 70th birthday of Professor Ilkka Tuominen. We
aim to cover topics that Ilkka has actively pursued during his long and
successful scientific career, namely spectroscopy and Doppler imaging of
stellar magnetic activity, stellar activity cycles and the flip-flop
phenomenon, and stellar dynamo theory.
If you plan to attend all or part of the program, or if you would like
to come to the special workshop on 5-6 October, please register on the
page indicated above. Please indicated if you would like to give a talk.
Alternatively, you may just email any of us.
The most up-to-date time table with preliminary allocation of chair persons is on
Understanding the origin of solar and stellar magnetic fields is
one of the central problems of physics and astrophysics, and a key
to understanding the cosmic magnetism, in general. There are two main
difficulties in studying this problem: 1) magnetic fields are generated
by turbulent dynamos in convection zones below the visible surface, not
accessible by direct observations; 2) solar and stellar magnetic activity
is a multi-scale phenomenon, involving physical processes on very small
scales, probably, below the current observational limit, and at the same
time showing remarkable large-scale spatial and temporal organizations
over a whole star. The prime target of our investigation is the Sun,
which serves as the Rosetta Stone in this field and holds the key to
unlocking the secrets of magnetic field generation in the Universe. The
most detailed observational data and theoretical models have been obtained
for the Sun, but a very significant progress has also been achieved in
observations and theories of magnetism on other stars.
Observationally, most efforts for solving the problem of solar and stellar
magnetism are focused on developing helio- and asteroseismology for
probing the structure and dynamics inside the Sun and stars and detecting
changes associated with magnetic fields, on high- resolution observations
for probing small-scale and even unresolved magnetic structures and
their organization and evolution, and on studying large-scale patterns
of sunspots and starspots and magnetic activity cycles.
Theoretically, this problem is addressed by developing physical models
at three different levels of the spatial and temporal domain: 1) direct
3D MHD simulations of small volumes of the convection zone with the
highest possible resolution to understand properties of MHD turbulence,
helicity, diffusion and saturation mechanisms; 2) 3D mean-field and full
MHD simulations of the interior of the Sun and stars for the global dynamo
on the scale of the activity cycles; 3) non-linear dynamical models to
investigate long-term evolution of the dynamo. These approaches have
been developed independently and quite successfully by different groups.
Data assimilation is a powerful analysis method in which observed
information is accumulated into dynamical models taking into account
physical constraints and properties. This approach makes possible
efficient and accurate estimations of physical properties which cannot
be observed directly, and obtain better understanding of the underlying
physics and develop forecast models.
At the beginning and the end of this program, we plan to hold short
(2-3 days) general discussion meetings. Also, during the program, we
will hold topical discussion sessions, as these are needed. Most work
will be done in focused working groups. In particular, we propose the
following initial tasks for discussion and investigation:
Physics of MHD turbulence and turbulent dynamo
Numerical dynamo simulations
Observational constraints on the solar and stellar dynamos