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AEGIS: Galaxy Spectral Energy Distributions from the X-Ray to Radio

N. P. Konidaris·P. Guhathakurta·K. Bundy·A. L. Coil·C. J. Conselice·M. C. Cooper·P. R. M. Eisenhardt·J. -S. Huang·R. J. Ivison·S. A. Kassin·E. N. Kirby·J. M. Lotz·J. A. Newman·K. G. Noeske·R. M. Rich·T. A. Small·C. N. A. Willmer·S. P. Willner
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Abstract

The All-wavelength Extended Groth Strip International Survey (AEGIS) team presents broad-band spectral energy distributions (SEDs), from X-ray to radio wavelengths, for 71 galaxies spanning the redshift range 0.55-1.16 ( ~0.7). Galaxies with secure redshifts were selected from a small (22 arcminute-square) sub-section of the Keck/DEIMOS galaxy redshift survey in the Extended Groth Strip field that has also been targeted for deep panchromatic imaging by Chandra (X-ray), GALEX (ultraviolet), Canada-France-Hawaii Telescope (optical), Hubble Space Telescope (optical/near infrared), Palomar Observatory (near infrared), Spitzer (mid/far infrared), and the Very Large Array (radio.) The absolute magnitude of the typical galaxy in our sample is M_B=-19.82. The ultraviolet to mid-infrared portion of their spectral energy distributions (SEDs) are found to be bracketed by two stellar-only model SEDs: an early burst followed by passive evolution and a constant star-formation rate since early times; this suggests that few of these galaxies are undergoing major starbursts. Approximately half the galaxies show a mid- to far-infrared excess relative to the model SEDs, consistent with thermal emission from interstellar dust. Two objects have power-law SEDs, indicating that they are dominated by active galactic nuclei; both are detected in X-rays. The galaxies are grouped by rest-frame color,quantitative optical morphology, and [OII] emission line strength (possible indicator of star formation). On average, the panchromatic SEDs of the galaxies, from the ultraviolet to the infrared, follow expected trends: redder SEDs are associated with red U-B, early-type morphology, and low [OII] emission, and vice versa for blue SEDs.

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N. P. Konidaris, P. Guhathakurta, K. Bundy, A. L. Coil, C. J. Conselice, M. C. Cooper, P. R. M. Eisenhardt, J. -S. Huang, R. J. Ivison, S. A. Kassin, E. N. Kirby, J. M. Lotz, J. A. Newman, K. G. Noeske, R. M. Rich, T. A. Small, C. N. A. Willmer, S. P. Willner. 2006-08-21. AEGIS: Galaxy Spectral Energy Distributions from the X-Ray to Radio. https://doi.org/10.1086/517929

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