Unprecedented rate of novae for northern observers. Final count is six in one year included the recurrent symbiotic nova RS Oph as the most important event. The photometric an spectroscopic coverage made at the Kolonica observatory is also unprecedented. The first results were presented at the Bezovec conference and will be published in the proceedings. In this article let me demonstrate the variety of light curves of these objects and how dense was our coverage. For more details see the presentation.
Besides the novae few words should be dedicated to SS Cyg. The prototype of regular dwarf novae systems. After more than century of periodic outbursts it presented typical Z Cam type behavior = standstill.
In the following gallery the light curves of all novae are plotted. Data collected in the AAVSO International Database are denoted with the name of the filter. Our data use larger symbols and letters DPV before the name of the filter. The times of acquired spectra are depicted on the top of figures. In the first row there are all spectra collected in the ARAS database. In the second row only low resolution spectra obtained at the Astronomical Observatory on Kolonica Saddle. Note the variety of the light curves. Almost all of them show some kind of oscillations.
Except the first one (V1391 Cas) all objects are still observable. However now is the time to look for correlations between optical oscillations and the energy flux in emission lines. This should be done during the cloudy winter nights.
For me the most exciting object is the fastest nova ever – V1674 Her. Not because of the rapid fading. The reason is a secret. The progenitor is an intermediate polar. It was known from the archive ZTF data. What is surprising is that the typical intermediate polar signal appeared just 23 days after the outburst when the brightness of the nova was still 7 mag above the quiescent. This the still unexplained secret.
SS Cyg – anomalous event
One of the most intensively observed variable stars. Prototype of long orbital period dwarf novae. And there is still space for surprise. The anomalous behavior started already in 2019. The outbursts became irregular, quiescence brighter. The optical irregularities are accompanied by increased flux in X rays. This was the reason for international observing campaign leaded by Dr. Mariko Kimura (RIKEN, Japan). She suggested that anomalous phenomenon was caused by an enhancement of accretion disk viscosity in the cool state. See the paper.
