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Spitzer Observations of High Redshift Radio Galaxies

N. Seymour·D. Stern·C. De Breuck
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Abstract

We present the results of a comprehensive Spitzer survey of 70 radio galaxies across 1<z<5.2. Using IRAC, IRS and MIPS imaging we determine the rest-frame AGN contribution to the stellar emission peak at 1.6um. The stellar luminosities are found to be consistent with that of a giant elliptical with a stellar mass of 10^11-12Msun. The mean stellar mass remains constant at \~10^11.5Msun up to z=3 indicating that the upper end of the mass function is already in place by this redshift. The mid-IR luminosities imply bolometric IR luminosities that would classify all sources as ULIRGs. The mid-IR to radio luminosity generally correlate implying a common origin for these emissions. The ratio is higher than that found for lower redshift, ie z<1, radio galaxies.

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N. Seymour, D. Stern, C. De Breuck. 2006-04-11. Spitzer Observations of High Redshift Radio Galaxies. https://arxiv.org/abs/astro-ph/0604226

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