J/MNRAS/386/1605 Luminous K-band selected QSOs from UKIDSS (Maddox+, 2008)
Luminous K-band selected quasars from UKIDSS.
Maddox N., Hewett P.C., Warren S.J., Croom S.M.
<Mon. Not. R. Astron. Soc., 386, 1605-1624 (2008)>
=2008MNRAS.386.1605M 2008MNRAS.386.1605M
ADC_Keywords: Surveys ; QSOs ; Photometry, infrared ; Photometry, SDSS
Keywords: surveys - quasars: general - infrared: general
Abstract:
The largest K-band flux-limited sample of luminous quasars to date has
been constructed from the UKIRT (UK Infrared Telescope) Infrared Deep
Sky Survey (UKIDSS) Large Area Survey Early Data Release, covering an
effective area of 12.8deg2. Exploiting the K-band excess (KX) of
all quasars with respect to foreground stars, including quasars
experiencing dust reddening and objects with non-standard spectral
energy distributions (SEDs), a list of targets suitable for
spectroscopic follow-up observations with the AAOmega multi-object
spectrograph is constructed, resulting in more than 200 confirmed
active galactic nuclei (AGN). KX selection successfully identifies as
quasar candidates objects that are excluded from the Sloan Digital Sky
Survey (SDSS) quasar selection algorithm due to their colours being
consistent with the stellar locus in optical colour space (with the
space density of the excluded objects agreeing well with results from
existing completeness analyses). Nearly half of the KX-selected
quasars with K≤17.0 at z<3 are too faint in the i band to have been
targeted by the SDSS quasar selection algorithm, revealing a large
population of quasars with red i-K colours.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 274 3154 Catalogue of KX-selected, spectroscopically
observed objects (Version of Sept 2007)
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See also:
VII/149 : Positions of high-redshift luminous quasars (Schneider+ 1992)
J/A+A/353/77 : Luminous quasars variability + polarization (Teerikorpi+ 2000)
J/MNRAS/372/425 : 2dF-SDSS Luminous Red Galaxy Survey, 2SLAQ (Cannon+, 2006)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [ULAS]
5- 23 A19 --- ULAS ULAS designation (JHHMMSS.ss+DDMMSS.s)
25- 36 A12 --- EDR [0-9] UKIDSS-EDR identification number
38- 47 F10.6 deg RAdeg Right ascension (J2000) in degrees
49- 58 F10.6 deg DEdeg Declination (J2000) in degrees
61- 62 I2 --- UCl UKIDSS Class (1)
65- 66 I2 --- S/G [-1/1] SDSS Class: -1 = star, 1 = gal
68- 75 F8.3 mag umag ?=-99.999 u SDSS PSF magnitude (2)
78- 84 F7.3 mag e_umag ?=-99.999 u SDSS PSF magnitude error
87- 93 F7.3 mag gmag ?=-99.999 g SDSS PSF magnitude (2)
96-102 F7.3 mag e_gmag ?=-99.999 g SDSS PSF magnitude error
105-111 F7.3 mag rmag ?=-99.999 r SDSS PSF magnitude (2)
114-120 F7.3 mag e_rmag ?=-99.999 r SDSS PSF magnitude error
123-129 F7.3 mag imag ?=-99.999 i SDSS PSF magnitude (2)
132-138 F7.3 mag e_imag ?=-99.999 i SDSS PSF magnitude error
141-147 F7.3 mag zmag ?=-99.999 z SDSS PSF magnitude (2)
150-156 F7.3 mag e_zmag ?=-99.999 z SDSS PSF magnitude error
159-165 F7.3 mag Ymag ?=-99.999 Y (0.97-1.07um) UKIDSS AperMag3
magnitude (2)
168-174 F7.3 mag e_Ymag ?=-99.999 Y UKIDSS AperMag3 magnitude error
177-183 F7.3 mag Jmag ?=-99.999 J UKIDSS AperMag3 magnitude (2)
186-192 F7.3 mag e_Jmag ?=-99.999 J UKIDSS AperMag3 magnitude error
195-201 F7.3 mag Hmag ?=-99.999 H UKIDSS AperMag3 magnitude (2)
204-210 F7.3 mag e_Hmag ?=-99.999 H UKIDSS AperMag3 magnitude error
213-219 F7.3 mag Kmag ?=-99.999 K UKIDSS AperMag3 magnitude (2)
222-228 F7.3 mag e_Kmag ?=-99.999 K UKIDSS AperMag3 magnitude error
230-236 F7.3 mag E(B-V) Extinction (3)
238-245 A8 --- Type Object Type (4)
247-253 F7.3 --- z Spectroscopic Redshift
(0.000 = Star, -99.999 = No redshift)
256 I1 --- q_Type [1/5] Confidence in identification, 5=best (5)
258-264 F7.1 --- S/N Signal to noise ratio, computed between
observed frame 6000-7000Å
266-274 A9 --- Com Comments (6)
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Note (1): UKIDSS Class as follows:
-3 = probable galaxy
-2 = probable star
-1 = star
0 = noise
1 = galaxy
Note (2): All magnitudes are on the Vega system, with AB-Vega conversions
from Hewett et al., 2006MNRAS.367..454H 2006MNRAS.367..454H. All magnitudes have been
corrected for Galactic reddening. A(Y), A(J), A(H), A(K) are from the
UKIDSS database. A(u)=5.155*E(B-V), A(g)=3.793*E(B-V),
A(r)=2.751*E(B-V), A(i)=2.086*E(B-V), A(z)=1.479*E(B-V)
Note (3): E(B-V) is from the UKIDSS database, based on the maps of Schlegel
et al., 1998ApJ...500..525S 1998ApJ...500..525S.
Note (4): Object Type as follows:
QSO = broad-line QSO
Type2 = Narrow-line AGN
BLLac = Featureless continuum
Abs = absorption-line galaxy
Em = emission-line galaxy
Astar = A-type star
Kstar = K-type star
Mstar = M-type star
Fringing = Fringing fibre
NoID = unclassified spectrum
NoFlux = No flux in spectrum
Note (5): Confidence in identification as follows:
5 = very confident
4 = confident
3 = No identification
2 = Fringing fibre
1 = No flux in spectrum
Note (6): Comments as follows:
SDSS = SDSS spectrum exists
BAL = Broad absorption line quasar
Fringing = Fringing fibre
NoComm = No comment
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 10-Nov-2008