5 papers
Surprising Variability of the Planetary Nebula IC 4997 = QV Sge
V. P. Arkhipova, M. A. Burlak, N. P. Ikonnikova +3
We present the results of a new epoch of a long-term photometric monitoring of the variable planetary nebula IC~4997. The integral light curves display a continuing brighteni…
Second Outburst of the Yellow Symbiotic Star LT Delphini
N. P. Ikonnikova, G. V. Komissarova, V. P. Arkhipova
We present the results of our photoelectric observations of the yellow symbiotic star LT Del over 2010-2018. The binary system LT Del, which consists of a bright K giant and…
Multicolor photometry and spectroscopy of the yellow supergiant with dust envelope HD 179821=V1427 Aquilae
N. P. Ikonnikova, O. G. Taranova, V. P. Arkhipova +5
We present the results of multicolor (UBVJHKLM) photometry (2009-2017) and low-resolution spectroscopy (2016-2017) of the semi-regular variable V1427 Aql=HD 179821, a yellow superg…
IRAS 19135+3937: An SRd variable as interacting binary surrounded by a circumbinary disc
N. Gorlova, H. Van Winckel, N. P. Ikonnikova +6
Semi-regular (SR) variables are not a homogeneous class and their variability is often explained due to pulsations and/or binarity. This study focuses on IRAS 19135+3937, an SRd va…
UBV Photometry of the Post-AGB Star IRAS 22272+5435=V354 Lac in 1990-2008
V. P. Arkhipova, N. P. Ikonnikova, G. V. Komissarova
New UBV-photometry obtained in 2000-2008 is presented for the post-AGB star IRAS 22272+5435=V354 Lac. The star showed semi-regular light variations with varying amplitudes. The max…