From kinematics to dynamics in thin galactic disk

A. Mathieu; M. R. Merrifield

doi:10.1046/j.1365-8711.2000.03646.x

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arXiv · astro-ph/0007227

From kinematics to dynamics in thin galactic disk

A. Mathieu·M. R. Merrifield

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Abstract

We present a method for recovering the distribution functions of edge-on thin axisymmetric disks directly from their observable kinematic properties. The most generally observable properties of such a stellar system are the line-of-sight velocity distributions of the stars at different projected radii along the galaxy. If the gravitational potential is known, then the general two-integral distribution function can be reconstructed using the shapes of the high-velocity tails of these line-of-sight distributions. If the wrong gravitational potential is adopted, then a distribution function can still be constructed using this technique, but the low-velocity parts of the observed velocity distributions will not be reproduced by the derived dynamical model. Thus, the gravitational potential is also tightly constrained by the observed kinematics.

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BibTeX RIS

A. Mathieu, M. R. Merrifield. 2000-07-17. From kinematics to dynamics in thin galactic disk. https://doi.org/10.1046/j.1365-8711.2000.03646.x

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