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The mass distribution in the innermost regions of Spiral Galaxies

Charu Ratnam·Paolo Salucci
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Abstract

We use high-spatial resolution ($\sim 100 pc$) rotation curves of 83 spiral galaxies to investigate the mass distribution of their innermost kpc. We show that, {\it in this region}, the luminous matter completely accounts for the gravitational potential and no dark component is required. The derived I-band disk mass-to-light ratios agree well with those obtained from population synthesis models and correlate with color in a similar way. We find strict upper limits of $\sim 10^7 M_\odot$ for the masses of compact bodies at the center of spirals, ruling out that these systems host the remnants of the quasar activity.

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Charu Ratnam, Paolo Salucci. 2000-08-08. The mass distribution in the innermost regions of Spiral Galaxies. https://doi.org/10.1016/s1384-1076(00)00038-5

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