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Do local analogs of Lyman Break Galaxies exist?

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 نشر من قبل Riccardo Scarpa
 تاريخ النشر 2007
  مجال البحث فيزياء
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The optical properties of a number of supercompact ultraviolet luminous galaxies (UVLG), recently discovered in the local Universe matching GALEX and Sloan Digital Sky Survey (SDSS) data, are discussed. Detailed re-analysis of the SDSS data for these and other similar but nearer galaxies shows that their surface brightness radial profile in both R and u bands is in most cases well described by an extended disk plus a central unresolved component (possibly a bulge). Since the SDSS pipeline used a single disk component to derive the half light radius of these UVLGs their size was severely underestimated. Consequently, the average UV surface brightness is much lower that previously quoted casting doubts on the claim that UVLGs are the local analogs of high redshift Lyman break galaxies.



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