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Color dependence of clustering of massive galaxies at 0.5$le z le$2.5: similar spatial distributions between green valley galaxies and AGNs

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 نشر من قبل Guanwen Fang
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present a measurement of the spatial clustering of rest-frame UV-selected massive galaxies at $0.5le z le 2.5$ in the COSMOS/UltraVISTA field. Considering four separate redshift bins with $Delta z=0.5$, we construct three galaxy populations, i.e., red sequence (RS), blue cloud (BC), and green valley (GV) galaxies, according to their rest-frame extinction-corrected UV colors. The correlation lengths of these populations are confirmed to be dependent on their rest-frame UV color and redshift: UV redder galaxies are found to be more clustered. In all redshift bins, the GV galaxies generally have medium clustering amplitudes and are hosted within dark matter halos whose masses are more or less between those of RS and BC galaxies; and the clustering amplitude of GV galaxies is close to that of AGNs in the same redshift bin, suggesting that AGN activity may be responsible for transforming galaxy colors. After carefully examining their stellar masses, we find that the clustering amplitudes of galaxy samples with different colors are all similar once they have a similar median stellar mass and that the median stellar mass alone may be a good predictor of galaxy clustering.



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