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Size And Properties Of The Narrow-Line Region In Seyfert-1 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Hass, R. Chini
Size And Properties Of The Narrow-Line Region In Seyfert-1 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Hass, R. Chini
Physics
Context.Spatially resolved emission-line spectroscopy is a powerful tool for determining the physical conditions in the narrow-line region (NLR) of active galactic nuclei (AGNs). We recently used optical long-slit spectroscopy to study the NLRs of a sample of six Seyfert-2 galaxies. We have shown that such an approach, in comparison to the commonly used [ ] narrow-band imaging alone, allows us to probe the size of the NLR in terms of AGN photoionisation. Moreover, several physical parameters of the NLR can be directly accessed. Aims.We here apply the same methods to study the NLR of six Seyfert-1 galaxies and …
Size And Properties Of The Narrow-Line Region In Seyfert-2 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Haas, R. Chini
Size And Properties Of The Narrow-Line Region In Seyfert-2 Galaxies From Spatially-Resolved Optical Spectroscopy, N. Bennert, B. Jungwiert, S. Komossa, M. Haas, R. Chini
Physics
Context. While [O III] narrow-band imaging is commonly used to measure the size of the narrow-line regions (NLRs) in active galactic nuclei (AGNs), it can be contaminated by emission from surrounding starbursts. Recently, we have shown that long-slit spectroscopy provides a valuable alternative approach to probe the size in terms of AGN photoionisation. Moreover, several parameters of the NLR can be directly accessed. Aims. We here apply the same methods developed and described for the Seyfert-2 galaxy NGC 1386 to study the NLR of five other Seyfert-2 galaxies by using high-sensitivity spatially-resolved optical spectroscopy obtained at the VLT and the …
The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister
The Radio Structure Of Radio-Quiet Quasars, C. Leipski, H. Falcke, N. Bennert, S. Hüttenmeister
Physics
Aims. We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies. Methods. We present and analyse high-sensitivity VLA radio continuum images of 14 radio-quiet quasars and six Seyfert galaxies. Results. Many of the low redshift radio-quiet quasars show radio structures that can be interpreted as jet-like outflows. However, the detection rate of extended radio structures on arcsecond scales among our sample decreases with increasing redshift and luminosity, most likely due to a lack of resolution. The morphologies of the detected radio emission indicate strong interactions of …
[O Iii] Profile Substructure In Radio-Quiet Quasars, C. Leipski, N. Bennert
[O Iii] Profile Substructure In Radio-Quiet Quasars, C. Leipski, N. Bennert
Physics
Interactions between the radio jet and the optical emission of the narrow-line region (NLR) are a well known phenomenon in Seyfert galaxies. Here, we present the study of possible jet-NLR interactions in five radio-quiet PG quasars with double or triple radio structure. High spatial and spectral resolution observations were carried out in the H-[O III] 5007 wavelength range. In all cases, there is evidence for [O III] profile substructure (shoulders, subpeaks, blueshifted "broad'' components) with different clarity. To measure the velocity, line width, intensity, and location of these [O III] components, several Gaussians were fitted. Often, the substructures are more …
Size And Properties Of The Nlr In The Seyfert-2 Galaxy Ngc1386, N. Bennert, B. Jungwiert, S. Komossa
Size And Properties Of The Nlr In The Seyfert-2 Galaxy Ngc1386, N. Bennert, B. Jungwiert, S. Komossa
Physics
We study the narrow-line region (NLR) of the Seyfert-2 galaxy NGC 1386 by means of long-slit spectroscopy obtained with FORS1 at the VLT. We use the galaxy itself for subtracting the stellar template, applying reddening corrections to fit the stellar template to the spectra of the NLR. The continuum gets steadily redder towards the nucleus. The spatial distribution of the reddening derived from the Balmer decrement differs from the continuum reddening, indicating dust within the NLR with a varying column density along the line of sight. Using spatially resolved spectral diagnostics, we find a transition between central line ratios falling …