Steeper, Flatter, or Just “salpeter”? Evidence from Galaxy Evolution and Galaxy Clusters
نویسنده
چکیده
A single-slope Salpeter IMF overpredicts the stellar M∗/LB ratio by about a factor of 2, which requires the IMF to be flatter below ∼ 1M⊙. On the other hand a Salpeter IMF for M > ∼ M⊙ 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 < ∼ 40M⊙ also predicts the observed amount of heavy elements (oxygen and silicon) in clusters of galaxies.
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