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On the shape of the light profiles of early-type galaxies

N. Caon·M. Capaccioli·M. D'Onofrio
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Abstract

We have obtained the best fit to the light profiles of a luminosity limited sample of elliptical and S0 galaxies with a power law \rn, letting the exponent remain free rather than keeping it fixed at $1/n=1/4$ as in the well known \GV formula. The introduction of a free parameter in the fitting formula (ranging from $n=0.5$ for $<\re>=0.3$ kpc to $n=16$ for $<\re>=25$ kpc) is justified by the existence of a good correlation between $n$ and the global galaxian parameters, such as total luminosity and scale-radius. This result seems to be in line with the segregation of properties between the `ordinary' and `bright' families of early-type galaxies, and has consequence for the claimed independence of the shape of galaxy profiles with respect to the Fundamental Plane parameters.

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N. Caon, M. Capaccioli, M. D'Onofrio. 1993-09-10. On the shape of the light profiles of early-type galaxies. https://doi.org/10.1093/mnras%2F265.4.1013

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