Volume 531, July 2011
|Number of page(s)||5|
|Published online||21 June 2011|
Remarks on the properties of elliptical galaxies in modified Newtonian dynamics
Universidad de Concepción, Departamento de Astronomia, Concepción, Chile
2 Argelander Institut für Astronomie, Universität Bonn, Bonn, Germany
3 Observatoire Astronomique de Strasbourg, CNRS, Strasbourg, France
4 Sterrenkundig Observatorium, Universiteit Gent, Gent, Belgium
Received: 17 January 2011
Accepted: 9 March 2011
Context. Two incorrect arguments against MOND in elliptical galaxies could be that the equivalent circular velocity curves tend to become flat at much larger accelerations than in spiral galaxies, and that the Newtonian dark matter halos are more concentrated than in spirals.
Aims. We compare published scaling relations for the dark halos of elliptical galaxies to the scaling relations expected for MONDian phantom halos.
Methods. We represent the baryonic content of galaxies by spherical profiles, and their corresponding MONDian phantom halos by logarithmic halos. We then derive the surface densities, central densities, and phase space densities and compare them with published scaling relations.
Results. We conclude that it is possible to recreate flat circular velocity curves at high acceleration in MOND, and that this happens for baryonic distributions described by Jaffe profiles in the region where the circular velocity curve is flat. Moreover, the scaling relations of the dark halos of ellipticals are remarkably similar to the scaling relations of phantom halos of MOND.
Key words: galaxies: elliptical and lenticular, cD / galaxies: kinematics and dynamics / gravitation
© ESO, 2011
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.