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Spitzer Observations of High Redshift Radio Galaxies

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 نشر من قبل Nick Seymour
 تاريخ النشر 2006
  مجال البحث فيزياء
والبحث باللغة English
 تأليف N. Seymour




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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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