Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-05-22
Astron.J.132:1426-1444,2006
Astronomy and Astrophysics
Astrophysics
v2: minor changes to match proofs. 23 pages, 15 figures, AJ in press. For version with high resolution figures, see http://w
Scientific paper
10.1086/506177
We present I-band photometry, long-slit optical spectroscopy, and new aperture synthesis HI observations for eight late-type spirals with rotation velocities in the range 243 km/s < V_{rot} < 308 km/s. The sample will be used to study the structure and angular momentum of disks at the high-mass end of the spiral galaxy population; here we discuss the basic properties of these ``fast rotators'', and derive hybrid optical/HI rotation curves for each. Despite the presence of HI warps and low-mass companions in many systems, their kinematics are regular and there is excellent agreement between optical and HI tracers near the optical radius r_{opt}. At high inclinations at which projection effects are negligible, the sample galaxies exhibit flat, featureless rotation curves out to their last measured points at 1.7r_{opt}--3.5 r_{opt}. The intermediate inclination systems are also consistent with a constant rotation amplitude for r > 0.5 r_{opt}. We therefore find no evidence for declining rotation curves at the high-mass end of the late-type spiral galaxy population. Combining our data with the compilation of spirals with reliable outer HI kinematics from the work of Casertano & van Gorkom, we find no convincing trends between logarithmic outer rotation curve slopes and rotation amplitudes or surface brightnesses for galaxies with V_{rot} > 220 km/s. Correlations between these slopes and morphological types or disk scale lengths are also marginal in this regime.
Giovanelli Riccardo
Spekkens Kristine
No associations
LandOfFree
The Structure of Rapidly Rotating Late-Type Spiral Galaxies: I. Photometry, HI and Optical Kinematics 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 Structure of Rapidly Rotating Late-Type Spiral Galaxies: I. Photometry, HI and Optical Kinematics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Structure of Rapidly Rotating Late-Type Spiral Galaxies: I. Photometry, HI and Optical Kinematics will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-16642