Photoelectric and spectroscopic observations of WW Vul

The results are given of photoelectric UBVR observations of the irregular variable WW Vul obtained during the seasons 1978-1981 and parallel spectroscopic observations in 1981 using the 2-m telescope with reciprocal dispersion 94 A/mm at H-gamma. The star was in the active phase for an appreciable fraction of the time of observation. Minima in the light of different depths and duration were found. The two-valued dependence between the light and color is confirmed. Spectra were taken at different levels of the brightness. In the phase of reduced brightness, changes were found in the intensities of the lines of hydrogen, calcium, and K Ca II, and also an ultraviolet excess, these being absent in the ascending branch of the curve and at the light maximum. At the different levels of brightness, the luminosity of WW Vul is also different. The hypothesis of screening of the star by dust particles is questioned.