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A Self-Consistent Dynamical Model for the {\sl COBE} Observed Galactic Bar and Its Application to Microlensing

HongSheng Zhao
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Abstract

A self-consistent stellar dynamical model for the Galactic bar is constructed from about 500 numerically computed orbits with an extension of the Schwarzschild technique. The model fits the {\sl COBE} found asymmetric boxy light distribution and the observed stellar kinematics of the bulge. The model potential is also consistent with the non-circular motions of the HI and CO velocity maps of the inner Galaxy. We also use the stellar bar model to construct a N-body model to study stability and a microlensing map towards the bulge, which can account for the observed optical depth and the event duration by the MACHO and OGLE collaborations. The technique used here can be applied to interpret light and velocity data of external bulges/bars and galactic nuclei.

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HongSheng Zhao. 1995-08-30. A Self-Consistent Dynamical Model for the {\sl COBE} Observed Galactic Bar and Its Application to Microlensing. https://arxiv.org/abs/astro-ph/9508146

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