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Measurement of the Spatial Cross-Correlation Function of Damped Lyman Alpha Systems and Lyman Break Galaxies

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 نشر من قبل Jeff Cooke
 تاريخ النشر 2005
  مجال البحث فيزياء
والبحث باللغة English
 تأليف J. Cooke




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We present the first spectroscopic measurement of the spatial cross-correlation function between damped Lyman alpha systems (DLAs) and Lyman break galaxies (LBGs). We obtained deep uBVRI images of nine QSO fields with 11 known z ~ 3 DLAs and spectroscopically confirmed 211 R < 25.5 photometrically selected z > 2 LBGs. We find strong evidence for an overdensity of LBGs near DLAs versus random, the results of which are similar to that of LBGs near other LBGs. A maximum likelihood cross-correlation analysis found the best fit correlation length value of r_0 = 2.9^(+1.4)_(-1.5) h^(-1)Mpc using a fixed value of gamma = 1.6. The implications of the DLA-LBG clustering amplitude on the average dark matter halo mass of DLAs are discussed.



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