V. P. Arkhipova

Spectroscopic studies of three novae

We present our spectroscopic observations of the novae V1425, V1493, and V1494 Aql carried out with the 125-cm telescope at the Crimean Station of the Sternberg Astronomical Institute in the wavelength range 4000–11000 Å. We measured the emission-line intensities, determined the nova shell expansion velocities from the line profile FWHMs and components, and estimated the interstellar reddening from the first members of the Balmer series. The chemical composition of the nova shells is analyzed. Nitrogen and oxygen were found to be overabundant in V1425 and V1494 Aql; the helium abundance turned out to be normal in the two stars.

Photometric variability and spectral features of the protoplanetary nebula LSII + 34° 26 = V1853 Cyg

AbstractWe present photoelectric and spectroscopic observations of the protoplanetary object V 1853 Cyg, a B supergiant with an IR excess. Over two years of its observations, the star exhibited rapid irregular light variations with amplitudes

Pulsations and long-term photometric variability of three candidates for protoplanetary nebulae

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Vorontsov-Velyaminov rows: Straight segments in the spiral arms of galaxies

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Observations of stellar objects at a shell boundary in the star-forming complex in the galaxy IC 1613

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Light variations in the candidate for protoplanetary objects HD 179821=V1427 Aql in 1899–1999

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