A study of emission-line variability of the nucleus in the Seyfert galaxy NGC 4151 in 1986-1988

Abstract

view Abstract Citations (10) References (65) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A study of emission-line variability of the nucleus in the Seyfert galaxy NGC 4151 in 1986-1988 Bochkarev, N. G. ; Shapovalova, A. I. ; Zhekov, S. A. Abstract Results are presented from observations of NGC 4151 optical spectra (in the 3960-4960 A spectral range) obtained by the TV scanner of the 6-m telescope at the Special Astrophysical Observatory of the USSR Academy of Sciences during 1986-1988. The nuclear spectra were found to be of the Sy 1.5 type, just as before the deep minimum of 1984. The emission line variability was less strong than in the 1970s and in the first half of the 1980s. Most of the narrow-line profiles differ from the Gaussian pattern. The narrow emission lines in the NGC 41651 spectrum assume a blueshift with respect to the host galaxy velocity. During 1986-1988, all broad lines were asymmetric and shifted blueward with respect to the narrow-line centers by 1000 km/s. After the deep minimum in 1984, the broad-emission symmetry in the NGC 4151 nucleus remained the same as it was before 1984. In 1987 the broad components of the H-beta and H-gamma lines decreased strongly and fell to a level comparable to that of 1984. In 1988 they increased approximately to the level of 1986. Publication: The Astronomical Journal Pub Date: October 1991 DOI: 10.1086/115953 Bibcode: 1991AJ....102.1278B Keywords: Active Galactic Nuclei; Seyfert Galaxies; Astronomical Spectroscopy; H Lines; Astrophysics full text sources ADS | data products SIMBAD (5) NED (2)