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arXiv · 1010.4174

On the connection between shape and stellar population in early-type galaxies

M. D'Onofrio·T. Valentinuzzi·G. Fasano·A. Moretti·D. Bettoni·B. M. Poggianti·B. Vulcani·J. Varela·J. Fritz·A. Cava·P. Kjaergaard·M. Moles·W. J. Couch·A. Dreller
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Abstract

We report on the discovery of a relation between the stellar mass $M^*$ of early-type galaxies (hereafter ETGs), their shape, as parametrized by the Sersic index $n$, and their stellar mass-to-light ratio $M^*/L$. In a 3D log space defined by these variables the ETGs populate a plane surface with small scatter. This relation tells us that galaxy shape and stellar population are not independent physical variables, a result that must be accounted for by theories of galaxy formation and evolution.

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M. D'Onofrio, T. Valentinuzzi, G. Fasano, A. Moretti, D. Bettoni, B. M. Poggianti, B. Vulcani, J. Varela, J. Fritz, A. Cava, P. Kjaergaard, M. Moles, W. J. Couch, A. Dreller. 2010-10-20. On the connection between shape and stellar population in early-type galaxies. https://doi.org/10.1088/2041-8205/727/1/l6

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