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Description
We present MIPS 24um observations of the Hubble Deep Field South taken with the Spitzer Space Telescope. The resulting image is 254arcmin^2^ in size and has a sensitivity ranging between ~12 and ~30uJy rms, with a median sensitivity of ~20uJy rms. A total of 495 sources have been catalogued with a signal-to-noise ratio greater than 5{sigma}. The source catalog is presented as well as source counts which have been corrected for completeness and flux boosting. The IR sources are then combined with MUSYC optical/NIR and ATHDFS radio observations to obtain redshifts and radio flux densities of the sample. We use the IR/radio flux density ratio (q_24_) to explore the IR-radio correlation for this IR sample and find q_24_=0.71+/-0.31 for sources detected in both IR and radio. The results are extended by stacking IR sources not detected in the radio observations and we derive an average q_24_ for redshift bins between 0<z<2.5. We find that the high-redshift (z>1) sources have an average q_24_ ratio which is better fit by local LIRG SEDs rather than local ULIRG SEDs, indicating that high-redshift ULIRGs differ in their IR/radio properties. So, ULIRGs at high-redshift have SEDs different from those found locally. Infrared-faint radio sources are examined, and while nine radio sources do not have an MIPS detection and are therefore radio-loud active galactic nuclei (AGNs), only one radio source has an extreme IRAC 3.6um to radio flux density ratio indicating it is a radio-loud AGN at z>1.
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