Internal Kinematics of Galaxies at z=0.25-0.45

Details Internal Kinematics of Galaxies at z=0.25-0.45 Internal Kinematics of Galaxies at z=0.25-0.45

1996-06-03

arxiv.org/abs/astro-ph/9606006v1

Astronomy and Astrophysics

Astrophysics

8 pages and 1 figure, AASTeX v4.0 2-column preprint style. Submitted to ApJ Letters. Also available through anonymous FTP at

Scientific paper

10.1086/306160

Low-mass starbursting galaxies have been proposed as the explanation of the excess of faint galaxies observed at intermediate redshifts. If this hypothesis is correct, then intermediate redshift galaxies should rotate more slowly than nearby galaxies with the same rest-frame luminosity. We present the results of a survey of the internal kinematics of intermediate redshift (z = 0.25-0.45) field galaxies to search for this effect. Using the Canada-France-Hawaii Telescope, spatially-resolved spectra of the [O II] $\lambda\lambda$ 3726- 3729 \AA doublet emission line have been obtained for 22 galaxies. V$_{\rm rot} $ sin i and [O II] disk scale lengths have been extracted from each galaxy spectrum using a Bayesian fitting technique. Galaxies in the sample are found to be $\sim$1.5-2.0 mag brighter than expected from their rotation velocity and the local Tully-Fisher (TF) relation. Low-mass galaxies exhibit a wider range of evolution relative to the TF relation than high-mass galaxies. The main source of uncertainty in this result is the large scatter in the local TF relation for late-type galaxies. Luminosity-dependent luminosity evolution neatly reconciles the lack of evolution seen in other works with the results of our survey. It is also found that the overall properties of [OII] kinematics at intermediate redshifts are varied. For example, 25% of the field galaxies in the sample have [OII] kinematics unrelated to rotation; [OII] emission is confined to the nucleus in most of these galaxies. Anomalous kinematics is found to be related to the presence of companions -- i.e. minor merger events. A Doppler ellipse similar to those found in local dwarf galaxies has been observed in a z = 0.35 galaxy, and may be interpreted as a supernova-driven supershell.

Affiliated with

Also associated with

No associations

Rating

Internal Kinematics of Galaxies at z=0.25-0.45 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 Internal Kinematics of Galaxies at z=0.25-0.45, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal Kinematics of Galaxies at z=0.25-0.45 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-408968