Extended gas in Seyfert 2 galaxies: implications for the nuclear source

Details Extended gas in Seyfert 2 galaxies: implications for the nuclear source Extended gas in Seyfert 2 galaxies: implications for the nuclear source

May 2003

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003mnras.341..449f&link_type=abstract

Monthly Notice of the Royal Astronomical Society, Volume 341, Issue 2, pp. 449-463.

Astronomy and Astrophysics

Astronomy

13

Galaxies: Active, Galaxies: Ism, Galaxies: Seyfert, X-Rays: Galaxies

Scientific paper

We use long-slit spectroscopic optical data to derive the properties of the extended emitting gas and the nuclear luminosity of a sample of 18 Seyfert 2 galaxies. From the emission-line luminosities and ratios we derive the density, reddening and mass of the ionized gas as a function of distance up to 2-4 kpc from the nucleus. Taking into account the geometric dilution of the nuclear radiation, we derive the radial distribution of covering factors and the minimum rate of ionizing photons emitted by the nuclear source. This number is an order of magnitude larger than that obtained from the rate of ionizing photons `intercepted' by the gas and measured from the Hα luminosity. A calibration is proposed to recover this number from the observed luminosity. The HeIIλ4686/Hβ line ratio was used to calculate the slope of the ionizing spectral energy distribution (SED), which in combination with the number of ionizing photons allows the calculation of the hard X-ray luminosities. These luminosities are consistent with those derived from X-ray spectra in the eight cases for which such data are available and recover the intrinsic X-ray emission in Compton-thick cases. Our method can thus provide reliable estimates of the X-ray fluxes in Seyfert 2 galaxies for the cases where it is not readily available. We also use the ionizing SED and luminosity to predict the infrared luminosity under the assumption that it is dominated by reprocessed radiation from a dusty torus, and find a good agreement with the observed IRAS luminosities.

Affiliated with

Also associated with

No associations

Rating

Extended gas in Seyfert 2 galaxies: implications for the nuclear source 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 Extended gas in Seyfert 2 galaxies: implications for the nuclear source, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extended gas in Seyfert 2 galaxies: implications for the nuclear source will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1464409