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J/ApJ/633/630       Low-mass stars found in CFHTLS              (Willott+, 2005)

First results from the Canada-France high-z quasar survey: constraints on the z=6 quasar luminosity function and the quasar contribution to reionization. Willott C.J., Delfosse X., Forveille T., Delorme P., Gwyn S.D.J. <Astrophys. J., 633, 630-637 (2005)> =2005ApJ...633..630W
ADC_Keywords: Stars, dwarfs ; QSOs ; Photometry, infrared Keywords: cosmology: observations - galaxies: active - quasars: general Abstract: We present preliminary results of a new quasar survey being undertaken with multicolor optical imaging from the Canada-France-Hawaii Telescope. The current data consist of 3.83deg2 of imaging in the i' and z' filters to a 10σ limit of z'<23.35. Near-infrared photometry of 24 candidate 5.7<z<6.4 quasars confirms them all to be low-mass stars, including two T dwarfs and four or five L dwarfs. Photometric estimates of the spectral type of the two T dwarfs are T3 and T6. Description: In this paper we use optical imaging from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) to search for high-redshift quasars. The data used come from the first official release: T0001. This release includes data in the four Deep Survey fields obtained during the period 2003 June-2004 July. Observations at J band were performed using the CFHT-IR camera at the CFHT. CFHT-IR is a HgCdTe 10242 array with pixel size 0.211". Observations were carried out in photometric conditions on UT 2003 November 9-10, 2004 May 4, and 2004 November 23-24. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 68 24 Table of low-mass stars found in the search for high-z quasars
See also: J/AJ/121/31 : High-redshift quasars in SDSS (Fan+, 2001) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 2 A2 --- Field Field designation 4- 9 A6 --- --- [CFHTLS] 11- 29 A19 --- CFHTLS Name ([WDF2005] CFHTLS in Simbad) 31 A1 --- l_i'mag Upper limit flag on i'mag 32- 36 F5.2 mag i'mag i' magnitude (in the AB system) (1) 38- 41 F4.2 mag e_i'mag ? Error in i'mag 43- 47 F5.2 mag z'mag z' magnitude (in the AB system) (1) 49- 52 F4.2 mag e_z'mag Error in z'mag 54 A1 --- l_Jmag Upper limit flag on Jmag 55- 59 F5.2 mag Jmag J magnitude (in the AB system) (1) 61- 64 F4.2 mag e_Jmag ? Error in Jmag 66- 68 A3 --- Note [Yes/No] Included in complete sample? (2)
Note (1): The magnitudes listed are total magnitudes derived from aperture magnitudes. Note (2): Indicates whether the object satisfies the i' and z' selection criteria that form the basis for our complete sample of quasar candidates for J-band imaging. These criteria are i'-z'≥1.5, σ(z')≤0.10, and z'<23.35. The three-color photometry indicates that all these objects are ultracool dwarfs.
History: From electronic version of the journal
(End) Marianne Brouty [CDS] 26-Jul-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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