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Comparing Chandra and SIRTF Observations for Obscured Starbursts and AGN at High Redshift

D. Weedman·V. Charmandaris·A. Zezas
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Abstract

Tracking the star formation rate to high redshifts requires knowledge of the contribution from both optically visible and obscured sources. The dusty, optically-obscured galaxies can be located by X-ray and infrared surveys. To establish criteria for selecting such sources based only on X-ray and infrared surveys, we determine the ratio of infrared to X-ray brightness that would be observed by SIRTF and Chandra for objects with the same spectral shapes as nearby starbursts if seen at high redshift. The parameter IR/X is defined as IR/X = (flux density observed in SIRTF MIPS 24 $μ$m filter in mJy)/(total flux observed within 0.5-2.0 keV in units of 10^-16 ergs\s\cm^2). Based on observations of NGC 4038/39 (``The Antennae''), NGC 3690+IC 694 (Arp 299 or Mkn 171), M 82, and Arp 220, nine starburst regions are compared using mid-infrared spectra taken by the Infrared Space Observatory (ISO) and X-ray spectra obtained with Chandra . The IR/X are determined as they would appear for 1 4 would not match any of the objects considered.

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D. Weedman, V. Charmandaris, A. Zezas. 2003-09-16. Comparing Chandra and SIRTF Observations for Obscured Starbursts and AGN at High Redshift. https://doi.org/10.1086/379785

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