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A Self-Consistent Dynamical Model for the COBE Detected Galactic Bar

HongSheng Zhao
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Abstract

A 3D steady state stellar dynamical model for the Galactic bar is constructed with 485 orbit building blocks using an extension of Schwarzschild technique. The weights of the orbits are assigned using non-negative least square method. The model fits the density profile of the COBE light distribution, the observed solid body stellar rotation curve, the fall-off of minor axis velocity dispersion and the velocity ellipsoid at Baade's window. We show that the model is stable. Maps and tables of observable velocity moments are made for easy comparisons with observation. The model can also be used to set up equilibrium initial conditions for N-body simulations to study stability. The technique used here can be applied to interpret high quality velocity data of external bulges/bars and galactic nuclei.

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HongSheng Zhao. 1995-12-11. A Self-Consistent Dynamical Model for the COBE Detected Galactic Bar. https://doi.org/10.1093/mnras%2F283.1.149

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