X-Ray and Radio Emission from Ultraviolet-selected Star-forming Galaxies at Redshifts 1.5 z 3.0 in the GOODS-North Field

Abstract
We have examined the stacked radio and X-ray emission from UV-selected galaxies spectroscopically confirmed to lie between redshifts 1.5 < z < 3.0 in the GOODS-North field to determine their average extinction and star formation rates (SFRs). The X-ray and radio data are obtained from the Chandra 2 Msec survey and the Very Large Array, respectively. There is a good agreement between the X-ray, radio, and de-reddened UV estimates of the average SFR for our sample of z~2 galaxies of ~50 solar masses per year, indicating that the locally-calibrated SFR relations appear to be statistically valid from redshifts 1.5 < z < 3.0. We find that UV-estimated SFRs (uncorrected for extinction) underestimate the bolometric SFRs as determined from the 2-10 keV X-ray luminosity by a factor of ~4.5 to 5.0 for galaxies over a large range in redshift from 1.0 < z < 3.5.Comment: 5 pages, 1 figure, Accepted by ApJ Letter
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