Stellar population gradients in Seyfert 2 galaxies. Northern sample

Details Stellar population gradients in Seyfert 2 galaxies. Northern sample Stellar population gradients in Seyfert 2 galaxies. Northern sample

2002-10-29

arxiv.org/abs/astro-ph/0210635v1

Mon.Not.Roy.Astron.Soc.339:772,2003

Astronomy and Astrophysics

Astrophysics

23 pages, 18 figures, MNRAS in press

Scientific paper

10.1046/j.1365-8711.2003.06222.x

We use high signal-to-noise ratio long-slit spectra in the 3600-4700A range of the twenty brightest northern Seyfert 2 galaxies to study the variation of the stellar population properties as a function of distance from the nucleus. In order to characterize the stellar population and other continuum sources (e.g. featureless continuum FC) we have measured equivalent widths Ws of six absorption features, four continuum colours and their radial variations, and performed spectral population synthesis as a function of distance from the nucleus. About half the sample has CaIIK and G-band W values smaller at the nucleus than at 1 kpc from it, due to a younger population and/or FC. The stellar population synthesis shows that, while at the nucleus, 75% of the galaxies present contribution > 20% of ages younger or equal than 100Myr and/or of a FC, this proportion decreases to 45% at 3 kpc. In particular, 55% of the galaxies have contribution > 10% of the 3 Myr/FC component (a degenerate component in which one cannot separate what is due to a FC or to a 3 Myr stellar population) at the nucleus, but only 25% of them have this contribution at 3 kpc. As reference, the stellar population of 10 non-Seyfert galaxies, spanning the Hubble types of the Seyfert (from S0 to Sc) was also studied. A comparison between the stellar population of the Seyferts and that of the non-Seyferts shows systematic differences: the contribution of ages younger than 1 Gyr is in most cases larger in the Seyfert galaxies than in non-Seyferts, not only at the nucleus but up to 1 kpc from it.

Affiliated with

Also associated with

No associations

Rating

Stellar population gradients in Seyfert 2 galaxies. Northern sample 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 Stellar population gradients in Seyfert 2 galaxies. Northern sample, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stellar population gradients in Seyfert 2 galaxies. Northern sample will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-533797