2 research outputs found
Flat galaxies with dark matter halos - existence and stability
We consider a model for a flat, disk-like galaxy surrounded by a halo of dark
matter, namely a Vlasov-Poisson type system with two particle species, the
stars which are restricted to the galactic plane and the dark matter particles.
These constituents interact only through the gravitational potential which
stars and dark matter create collectively. Using a variational approach we
prove the existence of steady state solutions and their nonlinear stability
under suitably restricted perturbations.Comment: 39 page
Hydrodynamical and radiative modeling of temporal H{\alpha} emission V/R variations caused by a discontinuous mass transfer in binaries
H{\alpha} emission V/R variations caused by a discontinous mass transfer in
interacting binaries with a rapidly rotating accreting star are modelled
qualititatively for the first time. The program ZEUS-MP was used for a
non-linear 3-D hydrodynamical modeling of a development of a blob of gaseous
material injected into an orbit around a star. It resulted in the formation of
an elongated disk with a slow prograde revolution. The LTE radiative transfer
program SHELLSPEC was used to calculate the H{\alpha} profiles originating in
the disk for several phases of its revolution. The profiles have the form of a
double emission and exhibit V/R and radial velocity variations. However, these
variations should be a temporal phenomenon since imposing a viscosity in given
model would lead to a circularization of the disk and fading-out of given
variations.Comment: accepted for a publication in Astronomical Journa