/ftp/cats/aliases/K/./KX_2_



==========================================================================
J/MNRAS/424/2876    Large area KX quasar catalogue           (Maddox+, 2012)
The following files can be converted to FITS (extension .fit or fit.gz)
	table4.dat table6.dat
==========================================================================
Query from: http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=J/MNRAS/424/2876
==========================================================================

drwxr-xr-x 22 cats archive 4096 Jan 24 16:17 [Up] drwxr-xr-x 4 cats archive 336 Jan 13 2023 [TAR file] -rw-r--r-- 1 cats archive 478 Dec 19 2022 .message -r--r--r-- 1 cats archive 12297 Jan 7 2014 ReadMe -rw-r--r-- 1 cats archive 865 Jan 7 2014 +footg5.gif -rw-r--r-- 1 cats archive 4284 Jan 7 2014 +footg8.gif -r--r--r-- 1 cats archive 92988 May 13 2013 table4.dat [txt] [txt.gz] [fits] [fits.gz] [html] -rw-r--r-- 1 cats archive 1487332 Sep 8 2013 table6.dat [txt] [txt.gz] [fits] [fits.gz] [html]
Beginning of ReadMe : J/MNRAS/424/2876 Large area KX quasar catalogue (Maddox+, 2012) ================================================================================ The large area KX quasar catalogue. I. Analysis of the photometric redshift selection and the complete quasar catalogue. Maddox N., Hewett P.C., Peroux C., Nestor D.B., Wisotzki L. <Mon. Not. R. Astron. Soc., 424, 2876-2895 (2012)> =2012MNRAS.424.2876M ================================================================================ ADC_Keywords: Surveys ; QSOs ; Photometry, SDSS ; Photometry, infrared Keywords: surveys - quasars: general - infrared: general Abstract: The results of a large area,  600deg^2^, K-band flux-limited spectroscopic survey for luminous quasars are presented. The survey utilizes the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) in regions of sky within the Sloan Digital Sky Survey (SDSS) footprint. The K-band excess (KX) of all quasars with respect to Galactic stars is exploited in combination with a photometric redshift/classification scheme to identify quasar candidates for spectroscopic follow-up observations. The data contained within this investigation will be able to provide new constraints on the fraction of luminous quasars reddened by dust with E(B-V)<=0.5mag. The spectroscopic sample is defined using the K-band, 14.0<=K<=16.6, and SDSS i-band limits of i=19.5, 19.7 and 22.0 over sky areas of 287, 150 and 196deg^2^, respectively. The survey includes >3200 known quasars from the SDSS and more than 250 additional confirmed quasars from the KX selection. A well-defined subsample of quasars in the redshift interval 1.0<=z<=3.5 includes 1152 objects from the SDSS and 172 additional KX-selected quasars. The quasar selection is >95 per cent complete with respect to known SDSS quasars and >95 per cent efficient, largely independent of redshift and i-band magnitude. The properties of the new KX-selected quasars confirm the known redshift-dependent effectiveness of the SDSS quasar selection and provide a sample of luminous quasars experiencing intermediate levels of extinction by dust. The catalogue represents an important step towards the assembly of a well-defined sample of luminous quasars that may be used to investigate the properties of quasars experiencing intermediate levels of dust extinction within their host galaxies or due intervening absorption line systems. Description: In order to maximize the dynamic range of the survey in absolute magnitude at fixed redshift, while ensuring adequate sampling of the brightest quasars, a 'wedding cake' survey geometry is adopted. Thus, the entire survey area is complete to the brightest limits, with a smaller subregion complete to fainter magnitudes and the smallest subregion complete to the faintest limits. Observations of the survey area utilized four telescopes (NTT, VLT, CA 2.2m and CA 3.5m) over three observing semesters between 2009 May and 2010 July.