Unknown selection effect simulates redshift periodicity in quasar number counts from Sloan Digital Sky Survey

  • J. G. Hartnett
Original Article


Discrete Fourier analysis on the quasar number count, as a function of redshift, z, calculated from the Sloan Digital Sky Survey DR6 release appears to indicate that quasars have preferred periodic redshifts with redshift intervals of 0.258, 0.312, 0.44, 0.63, and 1.1. However the same periods are found in the mean of the zConf parameter used to flag the reliability of the spectroscopic measurements. It follows that these redshift periods must result from some selection effect, as yet undetermined. It does not signal any intrinsic (quantized) redshifts in the quasars in Sloan survey data. However this result does not rule out the possibility as found in earlier studies of other data.


Quasars SDSS survey Redshift abundances Fourier analysis Selection effect 


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.School of Physicsthe University of Western AustraliaCrawleyAustralia

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