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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
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:
FileName Lrecl Records Explanations
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
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
Bytes Format Units Label Explanations
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)
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.
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); 2 = Fan et al. (2000AJ....119....1F); 3 = Fan et al. (2001, Cat. J/AJ/121/31); 4 = Zheng et al. (2000AJ....120.1607Z); 5 = Schneider et al. (2001AJ....121.1232S); 6 = Anderson et al. (2001, Cat. J/AJ/122/503); 7 = Schneider et al. (2005AJ....130..367S).
History: From electronic version of the journal References: Richards et al., Paper I 2004AJ....127.1305R
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 23-Oct-2006
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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