Rotation et masse du grand nuage de Magellan.
Abstract
Summary. From spectrographic observations at moderate dispersion (74 A mm ') of 151 supergiant stars belonging to the Large Magellanic Cloud, we derive a new position angle of the major axis at fi = 1800 which is consistent with previous values. The rotation curve shows clearly a keplerian branch starting at 204 and extending to 305 from the center of rotation. We have fitted our curve with Perek's model which gives a mass within 305 of the center estimated to 0.43 1010 M0 for n =2, and with Brandt's model from which we derive a total mass of 0.48 1010 M0. The latter gives the best solution, leading to a massluminosity ratio of 1.4 and a mass of neutral gastotal mass ratio of 0.10, both in agreement with values currently admitted for latetype spiral galaxies. A short study of residual velocities gives a velocity dispersion of 10 km s ' showing that the random motions are negligible. Key words: Large Magellanic Cloud  radial velocity  supergiants  rotation
 Publication:

Astronomy and Astrophysics
 Pub Date:
 October 1973
 Bibcode:
 1973A&A....28..165P