Mass Distribution and Gravitational Potential of the Milky Way
Abstract
Models of mass distribution in the Milky Way are discussed where those yielding the potential analytically are preferred. It is noted that there are three main contributors to the Milky Way potential: bulge, disc and dark halo. In the case of the disc the MiyamotoNagai formula, as simple enough, has shown as a very good solution, but it has not been able to satisfy all requirements. Therefore, improvements, such as adding new terms or combining several MiyamotoNagai terms, have been attempted. Unlike the disc, in studying the bulge and dark halo the flattening is usually neglected, which offers the possibility of obtaining an exact solution of the Poisson equation. It is emphasized that the Hernquist formula, used very often for the bulge potential, is a special case of another formula and the properties of that formula are analysed. In the case of the dark halo, the slopes of its cumulative mass for the inner and outer parts are explained through a new formalism presented here for the first time.
 Publication:

Open Astronomy
 Pub Date:
 April 2017
 DOI:
 10.1515/astro20170002
 Bibcode:
 2017OAst...26....1N
 Keywords:

 Galaxy: kinematics and dynamics;
 structure