J/AJ/132/999        SDSS quasar lens search                  (Oguri+, 2006)
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The Sloan Digital Sky Survey quasar lens search.
I. Candidate selection algorithm.
    Oguri M., Inada N., Pindor B., Strauss M.A., Richards G.T., Hennawi J.F.,
    Turner E.L., Lupton R.H., Schneider D.P., Fukugita M., Brinkmann J.
   <Astron. J., 132, 999-1013 (2006)>
   =2006AJ....132..999O
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ADC_Keywords: QSOs ; Gravitational lensing
Keywords: gravitational lensing - quasars: general

Abstract:
    We present an algorithm for selecting a uniform sample of
    gravitationally lensed quasar candidates from low-redshift (0.6<z<2.2)
    quasars brighter than i=19.1 that have been spectroscopically
    identified in the Sloan Digital Sky Survey (SDSS). Our algorithm uses
    morphological and color selections that are intended to identify
    small- and large-separation lenses, respectively. Our selection
    algorithm only relies on parameters that the SDSS standard image
    processing pipeline generates, allowing easy and fast selection of
    lens candidates. The algorithm has been tested against simulated SDSS
    images, which adopt distributions of field and quasar parameters taken
    from the real SDSS data as input. Furthermore, we take differential
    reddening into account. We find that our selection algorithm is almost
    complete down to separations of 1" and flux ratios of 10^-0.5^.

File Summary:
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 FileName   Lrecl  Records   Explanations
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ReadMe         80        .   This file
table1.dat     33      525   Completeness for double lenses
table2.dat    101       20   Quadruply lensed quasars used in the simulation
table3.dat     41      525   Completeness for quadruple lenses
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See also:
   J/A+A/340/371 : Quasar polarization (Hutsemekers+ 1998)
   J/ApJ/409/28  : Gravitationally Lensed Quasars (Maoz + 1993)
   http://www.sdss.org : SDSS Home Page

Byte-by-byte Description of file: table1.dat
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  Bytes Format Units  Label       Explanations
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  1-  5  F5.2  [-]    log(Fratio) Log (base 10) of the flux ratio
  7-  9  F3.1  arcsec Sep         Image Separation
 11- 15  F5.3  ---    Ctot        ]0/1[ Total Completeness
 17- 21  F5.3  ---    Cmor        ]0/1[ Completeness for morphological selection
 23- 27  F5.3  ---    Ccol        [0/1[ Completeness for color selection
 29- 33  F5.3  ---    Cboth       [0/0.3[ The fraction of lenses selected from
                                         both morphological and color selections
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Byte-by-byte Description of file: table2.dat
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   Bytes Format Units   Label     Explanations
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   1- 13  A13   ---     Name      Name of the quadruple lenses
  15- 19  A5    ---     Type      Type, based on visual inspection
  21- 25  F5.2  arcsec  Sep       Maximum separation between multiple images
  27- 30  F4.2  ---     fquad     Flux ratio between the brightest image and the
                                   image farthest from the brightest image
  32- 69  A38   ---     Ref       Reference (1)
  71-101  A31   ---     SName     Simbad name
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Note (1): The reference from which we adopt the image positions and fluxes
     for the simulation. For fluxes, we use those of the i-band (F814W for
     the Hubble Space Telescope data) image when the optical data are
     available. If not, we adopt those of the radio-band image. CASTLES
     corresponds to C. S. Kochanek et al., CASTLES survey,
     http://cfa-www.harvard.edu/castles/
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Byte-by-byte Description of file: table3.dat
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   Bytes Format Units   Label    Explanations
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   1- 13  A13   ---     Name     Name of quadruple lenses
  15- 17  F3.1  arcsec  Sep      Image Separation
  19- 23  F5.3  ---     Ctot     ]0/1[ Total Completeness
  25- 29  F5.3  ---     Cmor     ]0/1[ Completeness for morphological selection
  31- 35  F5.3  ---     Ccol     [0/1[ Completeness for color selection
  37- 41  F5.3  ---     Cboth    [0/1[ The fraction of lenses selected from
                                  both morphological and color selections
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History:
    From electronic version of the journal
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(End)                  Greg Schwarz [AAS], Patricia Vannier [CDS]    25-Apr-2008