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Steeper, Flatter, or Just "Salpeter"? Evidence from Galaxy Evolution and Galaxy Clusters

Alvio Renzini
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Abstract

A single-slope "Salpeter" IMF overpredicts the stellar M/L ratio of local elliptical galaxies by about a factor of 2, which requires the IMF to be flatter below about one solar mass. On the other hand a Salpeter IMF for stars more massive than the sun predicts an evolution with redshift of the fundamental plane of ellipticals in clusters which is in agreement with the observations and a formation at z>~3 for these galaxies. A "Salpeter" IMF for 1<M<40 solar masses also predicts the observed amount of heavy elements (oxygen and silicon) in clusters of galaxies.

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Alvio Renzini. 2004-10-14. Steeper, Flatter, or Just "Salpeter"? Evidence from Galaxy Evolution and Galaxy Clusters. https://doi.org/10.1007/978-1-4020-3407-7_43

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