Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395

Details Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395 Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395

1999-02-10

arxiv.org/abs/astro-ph/9902163v1

Astronomy and Astrophysics

Astrophysics

44 pages, Latex, includes 4 figures, Fig. 1 has 2 parts, all figures are encapsulated postscript except Fig. 3, which is just

Scientific paper

10.1086/307486

We have combined Hubble Space Telescope/Faint Object Spectrograph, ground-based, and Infrared Space Observatory spectra of the nucleus of NGC 4395, the least luminous and nearest known type 1 Seyfert galaxy. The spectra show emission lines from a wide range of ionization states and critical densities. We have generated multicomponent photoionization models of both the broad and narrow emission-line regions (BLR and NLR) to investigate the physical conditions in the emission-line gas and test the proposition that the source of ionization is the non-thermal continuum radiation emitted by the central source. We show that, with a minimum of free parameters, the model predictions match the observed emission-line ratios quite well. The elemental abundances appear to be subsolar, with even greater underabundance of nitrogen.From the size of the BLR predicted by the models, we estimate a central mass of a few x 10^5 solar masses, in reasonable agreement with estimates from the stellar kinematics. Finally, our results suggest that the covering factor of the emission-line gas is close to unity, and that the observed UV to X-ray continuum is absorbed by intervening NLR gas. We argue that high covering factor is responsible for the apparent flattening of the Baldwin relation in low luminosity AGN.

Affiliated with

Also associated with

No associations

Rating

Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Physical Conditions in the Emission Line Gas in the Extremely Low Luminosity Seyfert Nucleus of NGC 4395 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-461180