J/AJ/131/49 Gravitational lenses among z≥4.0 quasars (Richards+, 2006)
A snapshot survey for gravitational lenses among z≥4.0 quasars.
II. Constraints on the 4.0<z<5.4 quasar population.
Richards G.T., Haiman Z., Pindor B., Strauss M.A., Fan X., Eisenstein D.,
Schneider D.P., Bahcall N.A., Brinkmann J., Fukugita M.
<Astron. J., 131, 49-54 (2006)>
=2006AJ....131...49R 2006AJ....131...49R
ADC_Keywords: Gravitational lensing ; QSOs ; Photometry, SDSS
Keywords: early universe - galaxies: luminosity function, mass function -
gravitational lensing - quasars: general
Abstract:
We report on i-band snapshot observations of 157 Sloan Digital Sky
Survey quasars at 4.0<z<5.4 using the Advanced Camera for Surveys
on the Hubble Space Telescope (HST) to search for evidence of
gravitational lensing of these sources.
Description:
Images of the 157 quasars were acquired with the High Resolution
Camera (HRC) on the Advanced Camera for Surveys (ACS). Observations
were taken in the SDSS i-band (F775W). The Wide-Field Camera on ACS
has higher sensitivity in i than does the HRC but has substantially
higher overhead and is mildly undersampled. The exposure times were
640s for each object: 320s in each of two exposures to help in
cosmic-ray rejection.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 64 157 Table 1: Results of imaging 157 SDSS quasars
with 4<z<5.4
table2.dat 64 89 Table 2: Additional sources included in our
sample, but never observed by HST
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See also:
J/AJ/122/503 : SDSS u*g*r*i*z* photometry and redshift of QSOs
(Anderson+, 2001)
J/AJ/121/31 : High-redshift quasars in SDSS (Fan+, 2001)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSSJ The IAU name (G1)
20 A1 --- f_SDSSJ [*] Flag on SDSSJ (G2)
22- 26 F5.3 --- z Redshift
28- 33 F6.2 mag BMAG ? Absolute B band magnitude (1)
35- 39 F5.2 mag imag SDSS i band magnitude (G3)
41- 45 F5.2 mag imagH ? HST i band magnitude (G3)
47- 52 F6.4 --- Prob0 ? Lensing probability ignoring morphological
selection effects
54- 59 F6.4 --- Prob ? Lensing probability after accounting for
morphological selection effects
61- 62 A2 --- HST-ID Observation set identification (2)
64 I1 --- r_SDSSJ Discovery reference code for SDSSJ (G4)
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Note (1): Computed with the parameters given in Section 1.
Note (2): Related to the HST file naming convention. This is given to
facilitate archival use of these data. The program id for this
project was "8f3", thus the files for the first object have names
like j8f3aa011_crj.fits.
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Global Notes:
Note (G1): The SDSS image reprocessing can change the coordinates
[by ∼0.1"] and thus the name slightly; matching should thus be
done on coordinates, not names.
Note (G2): A "*" indicates object was selected without reference to its
morphological type (stellar vs. extended).
Note (G3): Uncorrected for Galactic reddening.
Note (G4): Reference for SDSSJ, defined as follows:
0 = object is published here for the first time;
1 = Fan et al. (1999AJ....118....1F 1999AJ....118....1F);
2 = Fan et al. (2000AJ....119....1F 2000AJ....119....1F);
3 = Fan et al. (2001, Cat. J/AJ/121/31);
4 = Zheng et al. (2000AJ....120.1607Z 2000AJ....120.1607Z);
5 = Schneider et al. (2001AJ....121.1232S 2001AJ....121.1232S);
6 = Anderson et al. (2001, Cat. J/AJ/122/503);
7 = Schneider et al. (2005AJ....130..367S 2005AJ....130..367S).
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History:
From electronic version of the journal
References:
Richards et al., Paper I 2004AJ....127.1305R 2004AJ....127.1305R
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 23-Oct-2006