高能天体物理研究组知识库

This proceedings contribution summarizes first results obtained from a systematic study of 2011 NLS1 galaxies, as presented in Zhou et al. (2006, ApJS, 166, 128). The sample was compiled by examining the spectral parameters of galaxies and QSOs derived from SDSS DR3 data. We discuss some preliminary results on the statistical properties of the sample, such as the fraction of NLS1, the properties of broad and narrow emission lines, and emission in other wavebands. The black hole mass - velocity dispersion relation for NLS1s was re-examined using the velocity dispersion values estimated from the stellar absorption spectra of the host galaxies. Preliminary result from an X-ray study for a small subset using data obtained by XMM-Newton is briefly discussed.