The pattern speed of the bar in NGC 4596
Abstract
The pattern speed is a defining parameter of any barred galaxy. A large number of model-dependent techniques have therefore been developed to derive the pattern speed. However, the only model-independent technique for measuring this quantity - the Tremaine-Weinberg method - has hitherto been applied to just one case, the SB0 galaxy NGC 936. In this paper, we apply the technique to a second system, the SBa galaxy NGC 4596. The resulting estimate for the pattern speed is Omega_p=52+/-13kms^-1kpc^-1. This result is corroborated by a spectrum obtained along the major axis of the bar in this system. The corotation radius associated with this pattern speed lies just beyond the end of the bar indicating a fast bar. Combining the bar major-axis spectra with data obtained from a Hubble Space Telescope WFPC2 image, we also find strong evidence for a nuclear disc.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 1999
- DOI:
- 10.1046/j.1365-8711.1999.02627.x
- Bibcode:
- 1999MNRAS.306..926G