Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic On-line Article (HTML)
· arXiv e-print (arXiv:astro-ph/0702609)
· Table of Contents
· References in the Article
· Citations to the Article (2) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Extended HI Rotation Curve of M31 using deep DRAO observations
Authors:
Carignan, C.; Chemin, L.; Foster, T.
Publication:
Galaxy Evolution Across the Hubble Time, Edited by F. Combes and J. Palous, Proceedings of the International Astronomical Union 2, IAU Symposium #235, held 14-17 August, 2006 in Prague, Czech Republic. Cambridge: Cambridge University Press, 2007., pp.193-193
Publication Date:
00/2007
Origin:
CUP
DOI:
10.1017/S1743921306005990
Bibliographic Code:
2007IAUS..235..193C

Abstract

Universite de Montreal, Montreal, Canada Recently, new single dish HI observations of M31 obtained with the Effelsberg and Green Bank telescopes made it possible to derive the rotation curve of the galaxy out to ˜35 kpc (Carignan et al. 2006, ApJ, 641, L112). Contrary to previous studies (Braun 1991) the rotation curve (RC) does not decline steadily from the centre out to the last measured velocity point but remains nearly constant at ˜ 226 km/s between 20 and 35 kpc. The total mass of M31 (luminous + dark) integrated in a radius of 35 kpc is ˜3.5x1011 solar masses. This is very similar to the mass of 2.8x1011 solar masses (for R < 31 kpc) found using kinematical data of planetary nebulae (Evans & Wilkinson 2000). When extrapolated to 50 kpc, this corresponds to a mass of 5x1011 solar, which is similar to the mass of the Milky Way (MW) within the same radius (Kochanek 1996). It thus appears that the two main members of the Local Group have comparable masses. However, the single dish observations are only for the approaching half of M31 because the gas on the receding side merges with the Galactic HI ˜ 0 km/s, which increases the uncertainties on the derived velocities. It was thus decided to get a mosaic of 5 fields using the DRAO synthesis array, combined with single dish observations. A great advantage of this data set, compared to the VLA data, is that it does not suffer from short spacing problems. The present data have sufficient spatial and velocity resolutions to fit separately the M31 and the MW gas and get kinematical information on both sides of the galaxy. Those new DRAO observations will be presented (HI distribution & velocity field) along with the new derived extended RC and a preliminary analysis of the mass distribution.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints