The Environment of Active Galaxies in the SDSS-DR4

Details The Environment of Active Galaxies in the SDSS-DR4 The Environment of Active Galaxies in the SDSS-DR4

2006-01-18

arxiv.org/abs/astro-ph/0601385v2

Astron.Astrophys. 451 (2006) 809-816

Astronomy and Astrophysics

Astrophysics

17 pages, 10 figures, accepted by A&A

Scientific paper

10.1051/0004-6361:20054354

We study the environment of active galaxies and compare it with that of star forming and normal galaxies. We extracted from the Fourth Data Release (DR4) of the Sloan Digitaly Sky Survey (SDSS) the galaxies in the redshift range 0.05 \le z \le 0.095 and with M(r) \le -20.0 (that is M* + 1.45). Emission line ratios and/or widths are used to separate Active Galactic Nuclei (AGN) from Star-Forming Galaxies (SFGs); AGN are classified as Seyfert-1 and Seyfert-2 galaxies according to emission line widths. The environmental properties, as defined by a density parameter and the number of companions, are compared for the different types of galaxies, taking into account the morphological type of the host galaxies. We find no difference in the large-scale environment of Seyfert-1 and Seyfert-2 galaxies; however, a larger fraction of Seyfert-2 (~2%) than Seyfert-1 (~1%) is found in systems which are smaller than r_{max} \le 100 kpc, mainly in low-density environments (pairs or triplets); for comparison, this fraction is ~2% for star forming galaxies and ~1% for normal galaxies. We find no evidence for a relation between large-scale environment properties and activity. If activity and environment are related, this more likely occurs on small scales (e.g. galaxy interaction, merging).

Affiliated with

Also associated with

No associations

Rating

The Environment of Active Galaxies in the SDSS-DR4 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 The Environment of Active Galaxies in the SDSS-DR4, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Environment of Active Galaxies in the SDSS-DR4 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-593858