2014/09/19 by C. Dumba, Cosmos Dumba, Dumba, Cosmos
Decision Sciences · Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Scientific Measurement and Uncertainty Evaluation #astro-ph.GA
paper · pdf · doi:10.48550/arxiv.1409.6174
55 pages, 150 figures, Masters Thesis
arxiv created 2014/09/19 · openalex publication_date 2014/09/19 · arxiv updated 2014/09/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The Broad Line Region of Active Galactic Nuclei is characterized by broad Balmer emission lines in their optical spectra. The broad Balmer emission lines are found to be asymmetric, some blue sided and others red sided in their asymmetry. One of the components behind the asymmetry is thought to be an accretion disk wind. We probe the accretion disk wind using the broad balmer emission line profiles. This asymmetry of the broad balma emission line profiles is measured in velocity space after a measurement of the line shift at percentiles from 0, in increaments of 10, up to 90. In addition, the Kurtosis Index is obtained at appropriate points of the emission lines' profiles. This study is based on many hundreds of SDSS spectra, starting with low redshift high signal to noise ratio spectra. We also consider a definite number in each bin of their FWHM, in bins of 1000 km/s (atleast 40 per bin), starting from 1000km/s to the very broad emission lines. We present how strong the asymmetry (by plotting Asymmetry Index as a function of percentile) of the broad/narrow lines (in percent) is, what the Kurtosis (R20, 80) is. We also present what the Asymmetry Index as a function of line width (FWHM), luminosity (V-band), core-radio flux and Ionization Degree. Key Words: AGN: Accretion Disk, Accretion Disk Wind - Line: Asymmetry, Balmer, Emission, Profiles