arXiv subjects
Publications and source records attributed to S. Frackowiak.
The results of time-resolved observations of SU UMa and U Gem obtained over two-years are presented. Both stars are prototypes of different classes of dwarf novae. We studied brightness variations on different time scales: orbital, QPO and flickering. The multicolor BVRI photometry allows to distinguisch the geometrical and physical sources of these variations.
We present photometric and spectral observation for four novae: V2362 Cyg, V2467 Cyg, V458 Vul, V2491 Cyg. All objects belongs to the "fast novae" class. For these stars we observed different departures from a typical behavior in the light curve and spectrum.
We present UBVRI photometry of three symbiotic stars ZZ CMi, TX CVn and AG Peg carried out from 1997 to 2008 in Piwnice Observatory near Torun. To search orbital periods of these stars Fourier analysis was used. For two of them, TX CVn and AG Peg, we have confirmed the earlier known periods. For ZZ CMi we found a relatively short period 218.59 days. Assuming, that the orbital period is twice longer (P=437.18 days), the double sine wave in the light curve can be interpreted by ellipsoidal effect.
The photometric and spectroscopic observational campaign organized for the 2008/9 eclipse of EE Cep revealed features, which indicate that the eclipsing disk in the EE Cep system has a multi-ring structure. We suggest that the gaps in the disk can be related to the possible planet formation.