Here we describe the first light of the novel 9-channel wide-field optical monitoring system with sub-second temporal resolution, Mini-MegaTORTORA, which is being tested now at Special Astrophysical Observatory on Russian Caucasus. The system is able
to observe the sky simultaneously in either wide (~900 square degrees) or narrow (~100 square degrees) fields of view, either in clear light or with any combination of color (Johnson B, V or R) polarimetric filters installed, with exposure times ranging from 100 ms to 100 s. The primary goal of the system is the detection of rapid -- with sub-second characteristic time-scales -- optical transients, but it may be also used for studying the variability of the sky objects on longer time scales.
Highly supercritical accretion discs are probable sources of dense optically thick axisymmetric winds. We introduce a new approach based on diffusion approximation radiative transfer in a funnel geometry and obtain an analytical solution for the ener
gy density distribution inside the wind assuming that all the mass, momentum and energy are injected well inside the spherization radius. This allows to derive the spectrum of emergent emission for various inclination angles. We show that self-irradiation effects play an important role altering the temperature of the outcoming radiation by about 20% and the apparent X-ray luminosity by a factor of 2-3. The model has been successfully applied to two ULXs. The basic properties of the high ionization HII-regions found around some ULXs are also easily reproduced in our assumptions.
