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Evidence for a Massive Dark Object in NGC 4350

E. Pignatelli·P. Salucci·L. Danese
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Abstract

In this work we build a detailed dynamic model for a S0 galaxy possibly hosting a central massive dark object (MDO). We show that the photometric profiles and the kinematics along the major and minor axes, including the h3 and h4 profiles, imply the presence of a central MDO of mass M = 1.5 - 9.7 10^8 solar masses, i.e. 0.3-2.8% of the mass derived for the stellar spheroidal component. Models without MDO are unable to reproduce the kinematic properties of the inner stars and of the rapidly rotating nuclear gas. The stellar population comprise of an exponential disc (27% of the light) and a diffuse spheroidal component (73% of the light) that cannot be represented by a simple de Vaucouleurs profile at any radius. The M/L ratios we found for the stellar components (respectively 3.3 and 6.6) are typical of those of disc and elliptical galaxies.

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E. Pignatelli, P. Salucci, L. Danese. 2000-08-28. Evidence for a Massive Dark Object in NGC 4350. https://doi.org/10.1046/j.1365-8711.2001.03942.x

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