Exploiting the full potential of photometric quasar surveys: Optimal power spectra through blind mitigation of systematics

  title={Exploiting the full potential of photometric quasar surveys: Optimal power spectra through blind mitigation of systematics},
  author={Boris Leistedt and Hiranya V. Peiris},
  journal={Monthly Notices of the Royal Astronomical Society},
  • B. Leistedt, H. Peiris
  • Published 25 April 2014
  • Physics
  • Monthly Notices of the Royal Astronomical Society
We present optimal measurements of the angular power spectrum of the XDQSOz catalogue of photometric quasars from the Sloan Digital Sky Survey. These measurements rely on a quadratic maximum likelihood estimator that simultaneously measures the auto- and cross-power spectra of four redshift samples, and provides minimum-variance, unbiased estimates even at the largest angular scales. Since photometric quasars are known to be strongly affected by systematics such as spatially-varying depth and… 

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