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Halos around edge-on disk galaxies in the SDSS

Stefano Zibetti·Simon D. M. White·Jon Brinkmann
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Abstract

We present a statistical analysis of halo emission for a sample of 1047 edge-on disk galaxies imaged in five bands by the Sloan Digital Sky Survey (SDSS). Stacking the homogeneously rescaled images of the galaxies, we can measure surface brightnesses as deep as mu_r~31 mag/arcsec^2. The results strongly support the almost ubiquitous presence of stellar halos around disk galaxies, whose spatial distribution is well described by a power-law $ρ\propto r^{-3}$, in a moderately flattened spheroid (c/a~0.6). The colour estimates in g-r and r-i, although uncertain, give a clear indication for extremely red stellar populations, hinting at old ages and/or non-negligible metal enrichment. These results support the idea of halos being assembled via early merging of satellite galaxies.

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Stefano Zibetti, Simon D. M. White, Jon Brinkmann. 2003-09-23. Halos around edge-on disk galaxies in the SDSS. https://doi.org/10.1111/j.1365-2966.2004.07235.x

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