Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution

Details Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution

2002-08-22

arxiv.org/abs/astro-ph/0208404v1

Astrophys.J.582:689-722,2003

Astronomy and Astrophysics

Astrophysics

78 pages with 23 embedded color figures + tables of galaxy structural parameters. Accepted for publication in the Astrophysica

Scientific paper

10.1086/344506

(Abridged) A robust analysis of galaxy structural parameters, based on the modeling of bulge and disk brightnesses in the BVRH bandpasses, is presented for 121 face-on and moderately inclined late-type spirals. Each surface brightness (SB) profile is decomposed into a sum of a generalized Sersic bulge and an exponential disk. The reliability and limitations of our bulge-to-disk (B/D) decompositions are tested with extensive simulations of galaxy brightness profiles (1D) and images (2D). Galaxy types are divided into 3 classes according to their SB profile shapes; Freeman Type-I and Type-II, and a third ``Transition'' class for galaxies whose profiles change from Type-II in the optical to Type-I in the infrared. We discuss possible interpretations of Freeman Type-II profiles. The Sersic bulge shape parameter for nearby Type-I late-type spirals shows a range between n=0.1-2 but, on average, the underlying surface density profile for the bulge and disk of these galaxies is adequately described by a double-exponential distribution. We confirm a coupling between the bulge and disk with a scale length ratio r_e/h=0.22+/-0.09, or h_bulge/h_disk=0.13+/-0.06 for late-type spirals, in agreement with recent N-body simulations of disk formation and models of secular evolution. This ratio increases from ~0.20 for late-type spirals to ~0.24 for earlier types. The similar scaling relations for early and late-type spirals suggest comparable formation and/or evolution scenarios for disk galaxies of all Hubble types.

Affiliated with

Also associated with

No associations

Rating

Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution 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 Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Structure of Disk Dominated Galaxies I. Bulge/Disk Parameters, Simulations, and Secular Evolution will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-401812