A systematic search for changing-look quasars in SDSS-II using difference spectra

  title={A systematic search for changing-look quasars in SDSS-II using difference spectra},
  author={Byron Carl Potts and Carolin Villforth},
  journal={Astronomy \& Astrophysics},
Context. ‘Changing-look quasars’ (CLQs) are active galactic nuclei (AGN) showing extreme variability that results in a transition from type 1 to type 2 AGN. The short timescales of these transitions present a challenge to the unified model of AGN and the physical processes causing these transitions remain poorly understood. CLQs also provide interesting samples for the study of AGN host galaxies since the central emission disappears almost entirely. Aims. Previous searches for CLQs have… 



A systematic search for changing-look quasars in SDSS

CLM acknowledges support from the STFC Consolidated Grant (Ref. St/M001229/1). NPR acknowledges support from the STFC and the Ernest Rutherford Fellowship scheme. KH acknowledges support from STFC

Publications of the Astronomical Society

  • Journal Supplement Series,
  • 1993

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