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patches are provided. Sources from overlapping tiles have been dealt with correctly and the parent tile information is recorded for each source. Aperture magnitudes, total magnitudes, and variable-aperture magnitudes (based on the image quality for each tile) are provided for each source. For a concise overview of the survey, the reader should consult Tables 6, 18 and 19. These tables provide all basic data on the survey coverage, seeing, exposure times, depth and completeness, astrometric and photometric errors. This release document is complemented by practical information at the Terapix T0007 release page and the T0007 “synoptic table” 5 . All data sets are available worldwide directly from both Terapix and the Canadian Astronomy Data Centre (CADC). In addition, searchable catalogues are made available at the Centre de Données astronomiques de Strasbourg (CDS) through VizieR while the entire survey can now be explored visually through the Aladin sky atlas in the HEALPix format. For users who prefer to produce their own stacks using the individual Elixir images, which are available at CADC along with their new weight-map produced by Terapix, a complete set of T0007 configuration files are listed in the Appendix A.2. In addition, a list of all images used in each Wide stack is given in Table 32. Weight maps and astrometric solution files are also provided for each individual image. All T0007 data products are immediately available worldwide along with the photometric redshifts which are released simultaneously (Ilbert et al. 2012). All the products can be downloaded from the CFHTLS T0007 release page at TERAPIX: http://terapix.iap.fr/rubrique.php?id_rubrique=268 6 For further information, the Terapix team can be contacted at terapix@iap.fr. CFHT, with support from CEA, has provided outstanding MegaPrime/MegaCam support, ensuring the steady collection of data of uniform quality through CFHT’s Queued Service Observing. CFHT provided data pre-processing and calibration (Elixir) and distribution (DADS). Overall survey integrity has been ensured by the CFHTLS Steering Group and oversight by the CFHT Science Advisory Committee. Data have been archived and distributed by CADC. It is important to acknowledge this collective effort in all works using the CFHTLS data. Following recommendations of the CFHT Executive Director and the CFHT Board of Directors, the following acknowledgement should be part of any publication using CFHTLS data: ”Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/IRFU, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at Terapix available at the Canadian Astronomy Data Centre as part of the Canada-France- Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. ” 7 2 Key new features in T0007 The main goal of the T0007 release versus the T0006 release was to improve the absolute and internal photometric calibration of the survey. This has been done by applying recipes adopted by the Supernova Legacy Survey (SNLS) for the SNLS/Deep fields to both the Deep and Wide fields of the CFHTLS. These recipes were used to generate a new set of photometric flat-fields (known as “Elixir B5/SNLS”) which have been used to run a new pre-processing by Elixir at CFHT on the entire CFHTLS raw data set. Consequently, all individual weight-maps and object catalogues have been re-generated at Terapix. 5 http://terapix.iap.fr/cplt/T0007/table_syn_T0007.html 6 http://terapix.iap.fr/rubrique.php?id_rubrique=268 7 http://www.cfht.hawaii.edu/Science/CFHTLS/cfhtlspublitext.html iii
Figure 1: Location of the four Deep and four Wide CFHTLS fields on the sky. A new series of shallow photometric calibration observations (a MegaCam program called “L99”) were made in photometric conditions towards the end of the CFHTLS survey. These observations pave in each filter the whole of the CFHTLS Wide within a short time window and are bracketed by observations of the SNLS tertiary standards on the Deep survey fields. These observations allowed the SNLS tertiary standards to be transfered to both the Deep and Wide surveys. This brings the absolute and relative photometric calibration over the entire survey at the 1% level or better in the g, r, i bands, 1.5% in the z band, and at the 2% level in the u ∗ band. Several other key aspects of the processing have been revised and improved for T0007: • A robust system is now used to correctly flag saturated objects at all stages of the processing; • For the Deep fields, two sets of stacks are now provided, one generated using a sigma-clipped combination algorithm (leading to a slightly higher signal-to-noise) and one using the standard median combination; • In the merged catalogues, object flags have been revised to provide object classification (star/galaxy), saturation, and masking in all bands; • An effective seeing-scaled aperture magnitude, MAG_IQ20, is introduced, although MAG_AUTO magnitudes remain the best estimate for extended sources, i.e. not seeing dominated profiles; • For each of the four Wide patches, merged catalogues have been generated and contain unique sources (overlapping objects from adjacent tiles are correctly dealt with); • The CFHTLS catalogue data products are made available for the first time at the Centre de Données astronomiques de Strasbourg (CDS) through VizieR, while the entire survey can now be explored visually through the Aladin sky atlas in the HEALPix format; Taken together, these changes represent a significant improvement in the scientific potential of the worldwide release T0007 (2012) compared to the six previous Terapix releases (2004-2009). iv
Page 1: T0007 : The Final CFHTLS Release Pa
Page 6 and 7: Contents 1 CFHTLS-T0007 Executive S
Page 8 and 9: B.1 Rescaling factors applied to de
Page 10 and 11: 33 Galaxy counts for the four Wide
Page 12 and 13: 30 Description of parameters listed
Page 14 and 15: B A B A B A B A B A B A B A B A B A
Page 16 and 17: constraints. Two series of Deep sta
Page 18 and 19: evealed minor problems (such as unu
Page 20 and 21: een preferable because of the highe
Page 22 and 23: Figure 5: Outputs of the SCAMP cali
Page 24 and 25: Figure 7: CFHTLS T0007 absolute pho
Page 26 and 27: Figure 8: Seeing FWHM distribution
Page 28 and 29: Figure 10: Aperture correction (def
Page 30 and 31: Filter u g r i z - ApCorr - ApCorr
Page 32 and 33: Figure 14: Photometric calibration
Page 34 and 35: Figure 17: Photometric calibration
Page 36 and 37: Figure 18: Matching between one L99
Page 38 and 39: • four (u, g, r , i/y, z) Wide pa
Page 40 and 41: W1 W2 N N E E W3 W4 N N E E Figure
Page 42 and 43: CFHTLS Reference center Total Total
Page 44 and 45: Each tile is centered at a well-def
Page 46 and 47: Field Parameter u ∗ g r i y z W1
Page 48 and 49: Figure 23: Distribution of exposure
Page 50 and 51: Figure 25: Distribution of the medi
Page 52 and 53: All CFHTLS Wide images: (mean CCD s
Page 54 and 55:
50% completeness are given for poin
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80% completeness limit (stars) 26.0
Page 58 and 59:
10 5 W1 W2 W3 10 5 W1 W2 W3 N gal 0
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Wide Field Magnitude range u ∗ g
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Wide Field Magnitude range u ∗ g
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paths. From the joint effort betwee
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Wide field External magnitude offse
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Wide field External rms errors with
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Figure 38: Comparison of one CFHTLS
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4.5.2 Absolute astrometric accuracy
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4.6 Outliers, stacks with exception
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Figure 40: Mean RA-DEC offsets betw
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Figure 42: Mean RA-DEC offsets betw
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W Cartesian CFHTLS Special filter V
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accurately reflect the integration
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Field Parameter u ∗ g r i y z D1-
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Field Parameter u ∗ g r i y z D1-
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76 Figure 43: Comparison of the (u
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Figure 44: Estimation of the intern
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5.4 Depth and completeness limits T
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D2 u−band (25% best−seeing imag
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log Ngal 0.5 mag −1 deg −2 5 4
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- there is one chi2 image per Wide
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File name Content Data Size Number
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File name Content Data Size Number
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6.3 Content of CFHTLS source catalo
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stacks made with the y-(i.MP9702) f
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Id Parameter Description Units Comm
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6.4 The QualityFITS input and outpu
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Figure 48: QFITS-out page of the W4
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102
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Figure 51: Upper panel: CFHTLS all-
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A CFHTLS T0007 Wide supplementary i
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Table 31 - Continued from previous
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A.2 List of images in each Wide sta
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Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
Page 132 and 133:
Page 134 and 135:
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DISTORT_GROUPS 1,1 # Polynom group
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#--------------------------- Photom
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#--------------------------- Photom
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#--------------------------- Photom
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#--------------------------- Backgr
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#--------------------------- Backgr
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#------------------------- Star/Gal
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#--------------------------- Star/G
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B.2 CFHTLS T0007 Deep configuration
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SCAMP astrometric run using interna
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SCAMP photometric run (D1,D2,D3,D4)
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B.2.2 SWarp stack configuration fil
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B.2.3 SWarp chi2-image configuratio
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B.2.4 SExtractor .ldac catalogue co
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B.2.5 SExtractor DUAL MODE .cat cat
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Acronyms & Abbreviations ASCII CADC
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References Astier, P., et al. 2006,
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