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Abstract: Using the Tuorla-Heidelberg model for the mass distribution of the Milky Way,I determine the rotation curve predicted by MOND. The result is in goodagreement with the observed terminal velocities interior to the solar radiusand with estimates of the Galaxy-s rotation curve exterior thereto. There areno fit parameters: given the mass distribution, MOND provides a good match tothe rotation curve. The Tuorla-Heidelberg model does allow for a variety ofexponential scale lengths; MOND prefers short scale lengths in the range 2.0 to2.5 kpc. The favored value of scale length depends somewhat on the choice ofinterpolation function. There is some preference for the `simple- interpolationfunction as found by Famaey and Binney. I introduce an interpolation functionthat shares the advantages of the simple function on galaxy scales while havinga much smaller impact in the solar system. I also solve the inverse problem,inferring the surface mass density distribution of the Milky Way from theterminal velocities. The result is a Galaxy with `bumps and wiggles- in bothits luminosity profile and rotation curve that are reminiscent of thosefrequently observed in external galaxies.



Author: Stacy McGaugh University of Maryland

Source: https://arxiv.org/







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