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Insights into Galaxy Evolution from Mid-infrared Wavelengths

Ranga-Ram Chary
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Abstract

In this paper, I have attempted to highlight key results from deep extragalactic surveys at mid-infrared wavelengths. I discuss advances in our understanding of dust enshrouded star-formation and AGN activity at 0 3 will become possible only with future facilities like ALMA. Currently, the presence of dust can only be assessed in a small fraction of the youngest starbursts at z>5 by looking for redshifted large equivalent width H_alpha emission in broadband filters like the IRAC 4.5 micron passband. H_alpha to UV ratios in these objects are a tracer of dust extinction and measuring this ratio in GOODS galaxies indicate dust in ~20% of star-forming galaxies at z>5. Finally, implications for reionization based on the measured stellar mass density and star-formation rates of galaxies at these redshifts are discussed.

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Ranga-Ram Chary. 2006-12-26. Insights into Galaxy Evolution from Mid-infrared Wavelengths. https://arxiv.org/abs/astro-ph/0612736

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