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Photometric entropy of stellar populations and related diagnostic tools

Alberto Buzzoni
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Abstract

We discuss, from a statistical point of view, some leading issues that deal with the study of stellar populations in fully or partially unresolved aggregates, like globular clusters and distant galaxies. A confident assessment of the effective number and luminosity of stellar contributors can provide, in this regard, a very useful interpretative tool to properly assess the observational bias coming from crowding conditions or surface brightness fluctuations. These arguments have led us to introduce a new concept of "photometric entropy" of a stellar population, whose impact on different astrophysical aspects of cluster diagnostic has been reviewed here.

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Alberto Buzzoni. 2005-09-20. Photometric entropy of stellar populations and related diagnostic tools. https://arxiv.org/abs/astro-ph/0509602

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