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We report photometric observations of the hidden symbiotic star SU Lyn in the optical bands. In five nights we detect a weak flickering in U band with amplitude of about 0.05 magnitudes. No intranight variations are found in B, V, g' and r' bands. This is one more indication that the secondary component is a white dwarf accreting at low accretion rate. We also searched for intranight variability of a dozen related object (RR Boo, RT Boo, AM Cyg, AG Peg, BF Cyg, NQ Gem, StHa190, V627 Cas, XX Oph, FS Cet and Y Gem) in which no variability above the observational errors is detected., Comment: 8 pages, to appear in Bulgarian Astron. Journal

We present a catalogue of point-like H��-excess sources in the Northern Galactic Plane. Our catalogue is created using a new technique that leverages astrometric and photomeric information from Gaia to select H��-bright outliers in the INT Photometric H�� Survey of the Northern Galactic Plane (IPHAS), across the colour-absolute magnitude diagram. To mitigate the selection biases due to stellar population mixing and to extinction, the investigated objects are first partitioned with respect to their positions in the Gaia colour-absolute magnitude space, and in the Galactic coordinates space, respectively. The selection is then performed on both partition types independently. Two significance parameters are assigned to each target, one for each partition type. These represent a quantitative degree of confidence that the given source is a reliable H��-excess candidate, with reference to the other objects in the corresponding partition. Our catalogue provides two flags for each source, both indicating the significance level of the H��-excess. By analysing their intensity in the H�� narrow band, 28,496 objects out of 7,474,835 are identified as H��-excess candidates with a significance higher than 3. The completeness fraction of the H�� outliers selection is between 3% and 5%. The suggested 5�� conservative cut yields a purity fraction of 81.9%., 20 pages, 23 figures

Hen 3-160 is reported in Belczynski et al.'s (2000) catalog as a symbiotic binary system with M7 giant donor. Using $V$- and $I$-band photometry collected over 20 years we have found that the giant is a Mira variable pulsating with 242.5-day period. The period-luminosity relation locates Hen 3-160 at the distance of about 9.4 kpc, and its Galactic coordinates ($l=267.7^{\circ}$, $b=-7.9^{\circ}$) place it $\sim$1.3 kpc above the disc. This position combined with relatively high proper motions (pm$_{\rm{RA}}=-1.5$ mas yr$^{-1}$, pm$_{\rm{DEC}}=+2.9$ mas yr$^{-1}$, Gaia DR2) indicates that Hen 3-160 has to be a Galactic extended thick-disc object. Our red optical and infrared spectra show the presence of ZrO and YO molecular bands that appear relatively strong compared to the TiO bands. Here we propose that the giant in this system is intrinsic S star, enriched in products of slow neutron capture processes occurring in its interior during an AGB phase which would make Hen 3-160 the first symbiotic system with Mira variable S star., accepted for publication at Acta Astronomica

We present optical photometric monitoring of KT Eri (Nova Eridani 2009), a He/N very fast nova which oubursted in November 2009. Our observations include BVRcIc brightness estimations as well as monitoring of the rapid brightness variations in V band. The characteristic times of these rapid changes are studied and compared with the observed in other novae., 4 pages, 1 figure, to appear in Stella Novae: Past and Future Decades conference proceedings, P. A. Woudt & V. A. R. M. Ribeiro (eds), ASPCS