The Osservatorio Astronomico di Palermo was one of the test sites for
the very accurate FLASH code, a 3-dimensional astrophysical
hydrodynamic code for supercomputers mainly developed at the "Flash Center", the
University of Chicago.
Palermo was the test site in which FLASH has been ported to Compaq
architectures. The FLASH code solves the compressible Euler equations
on a block-structured adaptive mesh, and its modular design permits the
introduction of additional physics and of different solvers.
The Palermo team has collaborated with the Flash Center to upgrade FLASH and
applies extensively the code to astrophysical systems.
The group in Palermo also develops new modules for FLASH which extend
the field of applicability of the code to other problems in
astrophysics, from solar and stellar coronae, to supernova remnants,
and to galaxy clusters halos. In particular, the new modules so far
developed and tested include:
- the non-equilibrium ionization effects of the most abundant
elements in astrophysical plasmas
- the thermal conduction according to the formulation of
Spitzer (1962)
- the radiative losses from an optically thin plasma
according to the Raymond spectral code and Peres et al. (1982) for
the chromosphere.
- the viscosity according to the formulation of Spitzer
(1962)
In this project, the Palermo team takes advantage of its long experience
in developing hydrodynamic codes for modeling astrophysical plasma and in
optimizing the codes for efficient parallel execution on high performance
computers. The group uses the computational resources at CINECA (Bologna,
Italy). Also INAF/OAPa is part of a consortium (Consorzio COMETA) which
has been recently funded to set up an advanced computational facility
in Sicily; a large HPC system will be available in Palermo (at the end
of this year) to which INAF/OAPa have full access.