Mapping the Stellar Dynamics of M31.

Authors :: Leibundgut, B.
Stanghellini, L.
Walsh, J. R.
Douglas, N. G.
Merrett, Helen
Merrifield, M.
Kuijken, K.
Romanowsky, A.
Douglas, N.
Napolitano, N.
Arnaboldi, M.
Capaccioli, M.
Freeman, K.
Gerhard, O.
Carter, D.
Evans, N.W.
Wilkinson, M.
Halliday, C.
Bridges, T.
Source :: Planetary Nebulae Beyond the Milky Way; 2006, p281-285, 5p
Publication Year :: 2006
Abstract: Using the Planetary Nebula Spectrograph, we have observed and measured the velocities for 2764 PNe in the disk and halo of the Andromeda galaxy. Preliminary analysis using a basic ring model shows a rotation curve in good agreement with that obtained from Hi data out to ~20 kpc. Some substructure has also been detected within the velocity field, which can be modeled as the continuation of the tidal-Cremnant known as the Southern Stream, as it passes through Andromeda's disk. [ABSTRACT FROM AUTHOR]