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Luminosity Functions of Elliptical Galaxies at z < 1.2

Myungshin Im·Richard E. Griffiths·Kavan U. Ratnatunga·Vicki L. Sarajedini
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Abstract

The luminosity functions of E/S0 galaxies are constructed in 3 different redshift bins (0.2 < z < 0.55, 0.55 < z < 0.8, 0.8 < z < 1.2), using the data from the Hubble Space Telescope Medium Deep Survey (HST MDS) and other HST surveys. These independent luminosity functions show the brightening in the luminosity of E/S0s by about 0.5~1.0 magnitude at z~1, and no sign of significant number evolution. This is the first direct measurement of the luminosity evolution of E/S0 galaxies, and our results support the hypothesis of a high redshift of formation (z > 1) for elliptical galaxies, together with weak evolution of the major merger rate at z < 1.

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Myungshin Im, Richard E. Griffiths, Kavan U. Ratnatunga, Vicki L. Sarajedini. 1996-02-08. Luminosity Functions of Elliptical Galaxies at z < 1.2. https://doi.org/10.1086/310018

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