Detection of a double-peaked H α component from the accretion disc of NGC 4958. Issue 1 (29th March 2019)

• Record Type: Journal Article
• Authors: Ricci, T V; Steiner, J E
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 486:Issue 1(2019)
• Page Start: 1138
• Page End: 1145
• Publication Date: 2019-03-29
• Subjects: accretion, accretion discs -- line: profiles -- techniques: imaging spectroscopy -- galaxies: active -- galaxies: individual: NGC 4958 -- galaxies: nuclei; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz919
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: Active Galactic Nuclei are objects associated with the presence of an accretion disc around supermassive black holes found in the very central region of galaxies with a well-defined bulge. In the optical range of the spectrum, a possible signature of the accretion disc is the presence of a broad double-peaked component that is mostly seen in H α. In this paper, we report the detection of a double-peaked feature in the H α line in the nucleus of the galaxy NGC 4958. The narrow-line region of this object has an emission that is typical of a low-ionization nuclear emission-line region galaxy, which is the usual classification for double-peaked emitters. A central broad component, related to the broad-line region of this object, is seen in H α and also in H β. We concluded that the double-peaked emission is emitted by a circular relativistic Keplerian disc with an inner radius ξi = 570 ± 83, an outer radius ξo = 860 ± 170 (both in units of GM SMBH / c 2 ), an inclination to the line of sight i = 27.2 ± 0.7° and a local broadening parameter σ = 1310 ± 70 km s −1 .