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J/A+A/457/79   VIMOS VLT Deep Survey: faint type-1 AGN sample (Gavignaud+, 2006)

The VIMOS VLT Deep Survey: the faint type-1 AGN sample. Gavignaud I., Bongiorno A., Paltani S., Mathez G., Zamorani G., Moller P., Picat J.P., Le Brun V., Marano B., Le Fevre O., Bottini D., Garilli B., Maccagni D., Scaramella R., Scodeggio M., Tresse L., Vettolani G., Zanichelli A., Adami C., Arnaboldi M., Arnouts S., Bardelli S., Bolzonella M., Cappi A., Charlot S., Ciliegi P., Contini T., Foucaud S., Franzetti P., Guzzo L., Ilbert O., Iovino A., Mccracken H.J., Marinoni C., Mazure A., Meneux B., Merighi R., Pello R., Pollo A., Pozzetti L., Radovich M., Zucca E., Bondi M., Busarello G., Cucciati O., De La Torre S., Gregorini L., Lamareille F., Mellier Y., Merluzzi P., Ripepi V., Rizzo D., Vergani D. <Astron. Astrophys., 457, 79-90 (2006)> =2006A&A...457...79G
ADC_Keywords: Surveys ; Active gal. nuclei ; Redshifts ; Photometry, UBVRI Keywords: catalogs - surveys - galaxies: active - galaxies: Seyfert - quasars: general Abstract: We present the type-1 active galactic nuclei (AGN) sample extracted from the VIMOS VLT Deep Survey's first observations of 21000 spectra in 1.75°2. This sample, which is purely magnitude-limited and free of morphological or color-selection biases, contains 130 broad-line AGN (BLAGN) spectra with redshift up to 5. Our data are divided into a wide (IAB≤22.5) and a deep (IAB≤24) subsample containing 56 and 74 objects, respectively. Because of its depth and selection criteria, this sample is uniquely suited for studying the population of faint type-1 AGN. Our measured surface density (∼472±48 BLAGN per square degree with IAB≤24) is significantly higher than that of any other optically selected sample of BLAGN with spectroscopic confirmation. By applying a morphological and color analysis to our AGN sample, we find that (1) ∼23% of the AGN brighter than IAB=22.5 are classified as extended, and this percentage increases to ∼42 for those with z<1.6; (2) a non-negligible fraction of our BLAGN are lying close to the color-space area occupied by stars in the u*-g' versus g'-r' color-color diagram. This leads us to the conclusion that the classical optical-ultraviolet preselection technique, if employed at such deep magnitudes (IAB=22.5) in conjuction with a preselection of point-like sources, can miss up to ∼35% of the AGN population. Finally, we present a composite spectrum of our sample of objects. While the continuum shape is very similar to that of the SDSS composite at short wavelengths, it is much redder than that of the SDSS composite at λ≥3000Å. We interpret this as due to significant contamination from emission of the host galaxies, as expected from the faint absolute magnitudes sampled by our survey. Description: The B, V, R, and I observations were performed from November 1999 to October 2000 at the 3.6m Canada-France-Hawaii Telescope, with the CFH12K wide-field mosaic camera. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 93 115 Broad-line AGN (BLAGN) with secure redshift (flags 14 and 13) tablea2.dat 119 15 BLAGN with a single emission line detected and more than one possible redshift (flag 19)
See also: III/250 : The VIMOS VLT deep survey (VVDS-DEEP) (Le Fevre+ 2005) J/A+A/428/1043 : Redshifts from VIMOS VLT Deep Survey (Le Fevre+, 2004) Byte-by-byte Description of file: tablea1.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Field Field 9 A1 --- Sample [dw] deep (d, IAB≤22.5) or wide (w, IAB≤24) sample 11- 12 I2 --- Nagn Number of AGN in the field 14- 22 I9 --- VVDS Object designation number 24- 25 I2 h RAh Right ascension (J2000) 27- 28 I2 min RAm Right ascension (J2000) 30- 34 F5.2 s RAs Right ascension (J2000) 36 A1 --- DE- Declination sign (J2000) 37- 38 I2 deg DEd Declination (J2000) 40- 41 I2 arcmin DEm Declination (J2000) 43- 47 F5.2 arcsec DEs Declination (J2000) 49- 54 F6.4 --- z Redshift 56- 57 I2 --- Flag [13,14] BLAGN flag (1) 58 A1 --- n_Flag [SF] Note on Flag (2) 60- 64 F5.2 mag Imag I magnitude in AB system 66- 70 F5.2 mag Bmag ?=- B magnitude in AB system 72- 76 F5.2 mag Vmag ?=- V magnitude in AB system 78- 82 F5.2 mag Rmag ?=- R magnitude in AB system 84- 93 A10 --- Morph Morphological classification for objects with IAB<22.5 (G1)
Note (1): Flags as follows: 13 = BLAGN with only one line detection but with the redshift secured from other informations such as: - no other possible identification for the given wavelength range - an intervening absorption-line system is detected, which this leaves only one redshift solution for the BLAGN - strong iron features, so-called "bumps", are detected - a second line is marginally detected 14 = BLAGN with secure redshift measurement (i.e.: two lines or more) Note (2): Note on Flags as follows: F = AGN re-observed in the 3800-6500 range with FORS1 in our follow-up program. S = Redshift confirmed by matching the catalog from Szokoly et al. (2004, Cat. J/ApJS/155/271).
Byte-by-byte Description of file: tablea2.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Field Field 9 A1 --- Sample [dw] deep (d, IAB≤22.5) or wide (w, IAB≤24) sample 11- 12 I2 --- Nagn Number of AGN in the field 14- 22 I9 --- VVDS Object designation number 24- 25 I2 h RAh Right ascension (J2000) 27- 28 I2 min RAm Right ascension (J2000) 30- 34 F5.2 s RAs Right ascension (J2000) 36 A1 --- DE- Declination sign (J2000) 37- 38 I2 deg DEd Declination (J2000) 40- 41 I2 arcmin DEm Declination (J2000) 43- 47 F5.2 arcsec DEs Declination (J2000) 49- 52 I4 0.1nm lambda Wavelength observed 54- 59 F6.4 --- z1 Redshift solution 60 A1 --- n_z1 [a-d] identification of the emission line (1) 62- 67 F6.4 --- z2 Redshift solution 68 A1 --- n_z2 [a-d] identification of the emission line (1) 70- 75 F6.4 --- z3 ? Redshift solution 76 A1 --- n_z3 [a-d] identification of the emission line (1) 78- 83 F6.4 --- z4 ? Redshift solution 84 A1 --- n_z4 [a-d] identification of the emission line (1) 86- 90 F5.2 mag Imag I magnitude in AB system 92- 96 F5.2 mag Bmag ?=- B magnitude in AB system 98-102 F5.2 mag Vmag ?=- V magnitude in AB system 104-108 F5.2 mag Rmag ?=- R magnitude in AB system 110-119 A10 --- Morph Morphological classification for objects with IAB<22.5 (G1)
Note (1): Note on redshift solution as follows: a = Emission line identified as Hα b = Emission line identified as MgII c = Emission line identified as C III] d = Emission line identified as CIV
Global notes: Note (G1): Objects in the VVDS-CDFS field are not classified. See Sect. 7.1.
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Apr-2007
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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