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Wide Field Multiband Imaging of Low Redshift Quasar Environments

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 نشر من قبل Jennifer Scott
 تاريخ النشر 2015
  مجال البحث فيزياء
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We present photometry of the large scale environments of a sample of twelve broad line AGN with $0.06 < z < 0.37$ from deep images in the SDSS $u$, $g$, $r$, and $i$ filters taken with the 90Prime prime focus camera on the Steward Observatory Bok Telescope. We measure galaxy clustering around these AGN using two standard techniques: correlation amplitude (B$_{gq}$) and the two point correlation function. We find average correlation amplitudes for the 10 radio quiet objects in the sample equal to (9$pm$18, 144$pm$114, -39$pm$56, 295$pm$260) Mpc$^{1.77}$ in ($u$, $g$, $r$, $i$), all consistent with the expectation from galaxy clustering. Using a ratio of the galaxy-quasar cross-correlation function to the galaxy autocorrelation function, we calculate the relative bias of galaxies and AGN, $b_{gq}$. The bias in the $u$ band, $b_{gq}=3.08pm0.51$ is larger compared to that calculated in the other bands, but it does not correlate with AGN luminosity, black hole mass, or AGN activity via the luminosity of the [OIII] emission line. Thus ongoing nuclear accretion activity is not reflected in the large scale environments from $sim$10 h$^{-1}$ kpc to $sim$0.5 h$^{-1}$ Mpc and may indicate a non-merger mode of AGN activity and/or a significant delay between galaxy mergers and nuclear activity in this sample of mostly radio quiet quasars.



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