J/A+A/562/A23 VIMOS Public Extragalactic Survey (VIPERS) DR1 (Garilli+, 2014)
The VIMOS Public Extragalactic Survey (VIPERS).
First Data Release of 57204 spectroscopic measurements.
Garilli B., Guzzo L., Scodeggio M., Bolzonella M., Abbas U., Adami C.,
Arnouts S., Bel J., Bottini D., Branchini E., Cappi A., Coupon J.,
Cucciati O., Davidzon I., De Lucia G., De La Torre S., Franzetti P.,
Fritz A., Fumana M., Granett B.R., Ilbert O., Iovino A., Krywult J.,
Le Brun V., Le Fevre O., Maccagni D., Malek K., Marulli F., Mccracken H.J.,
Paioro L., Polletta M., Pollo A., Schlagenhaufer H., Tasca L.A.M.,
Tojeiro R., Vergani D., Zamorani G., Zanichelli A., Burden A., Di Porto C.,
Marchetti A., Marinoni C., Mellier Y., Moscardini L., Nichol R.C.,
Peacock J.A., Percival W.J., Phleps S., Wolk M.
<Astron. Astrophys., 562, A23-23 (2014)>
=2014A&A...562A..23G 2014A&A...562A..23G
ADC_Keywords: Surveys ; Galaxy catalogs ; Photometry, SDSS
Keywords: galaxies: distances and redshifts - galaxies: statistics -
galaxies: fundamental parameters - cosmology: observations -
catalogs - structure of Universe large-scale
Abstract:
We present the first Public Data Release (PDR-1) of the VIMOS Public
Extragalactic Survey (VIPERS). It comprises 57204 spectroscopic
measurements together with all additional information necessary for
optimal scientific exploitation of the data, in particular the
associated photometric measurements and quantification of the
photometric and survey completeness. VIPERS is an ESO Large Programme
designed to build a spectroscopic sample of ≃100000 galaxies with
iAB<22.5 and 0.5<z<1.2 with high sampling rate (≃45%). The survey
spectroscopic targets are selected from the CFHTLS-Wide five-band
catalogues in the W1 and W4 fields. The final survey will cover a
total area of nearly 24 deg2, for a total comoving volume between
z=0.5 and 1.2 of ≃4x107(Mpc/h)3 and a median galaxy redshift of
z≃0.8. The release presented in this paper includes data from
virtually the entire W4 field and nearly half of the W1 area, thus
representing 64% of the final dataset. We provide a detailed
description of sample selection, observations and data reduction
procedures; we summarise the global properties of the spectroscopic
catalogue and explain the associated data products and their use, and
provide all the details for accessing the data through the survey
database (http://vipers.inaf.it) where all information can be queried
interactively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
w1ppdr1.dat 328 622730 VIPERS W1 photometric catalog
w4ppdr1.dat 328 709851 VIPERS W4 photometric catalog
w1spdr1.dat 105 30523 VIPERS W1 spectroscopic catalog
w4spdr1.dat 105 30698 VIPERS W4 spectroscopic catalog
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See also:
II/317 : The CFHTLS Survey (T0007 release) (Hudelot+ 2012)
III/250 : The VIMOS VLT deep survey (VVDS-DEEP) (Le Fevre+ 2005)
Byte-by-byte Description of file: w1ppdr1.dat w4ppdr1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- --- [VIPERS]
8- 16 I9 --- VIPERS VIPERS number (G1)
18- 26 I9 --- Num Internal id number (identical to VIPERS)
28- 37 F10.6 deg RAdeg J2000 Righ Ascension in decimal degrees (alpha)
39- 47 F9.6 deg DEdeg J2000 Declination in decimal degrees (delta)
49- 56 F8.4 mag selmag iAB selection magnitude. The selection
magnitude comes from CFHTLS T0005 catalogues
58- 65 F8.4 mag e_selmag Error on the selection magnitude
67- 74 F8.4 mag umag ?=-99 u magnitude (AB) from CFHTLS T0005 (2)
76- 83 F8.4 mag gmag ?=-99 g magnitude (AB) from CFHTLS T0005 (2)
85- 92 F8.4 mag rmag ?=-99 r magnitude (AB) from CFHTLS T0005 (2)
94-101 F8.4 mag imag i magnitude (AB) from CFHTLS T0005 (2)
103-110 F8.4 mag zmag ?=-99 z magnitude (AB) from CFHTLS T0005 (2)
112-119 F8.4 mag e_umag ?=-99 rms uncertainty on umag (AB) (erru)
121-128 F8.4 mag e_gmag ?=-99 rms uncertainty on gmag (AB) (errg)
130-137 F8.4 mag e_rmag ?=-99 rms uncertainty on rmag (AB) (errr)
139-146 F8.4 mag e_imag rms uncertainty on imag (AB) (erri)
148-155 F8.4 mag e_zmag ?=-99 rms uncertainty on zmag (AB) (errz)
157-164 F8.4 mag uT07 ?=-99 u magnitude (AB) from CFHTLS T0007 (3)
166-173 F8.4 mag gT07 ?=-99 g magnitude (AB) from CFHTLS T0007 (3)
175-182 F8.4 mag rT07 ?=-99 r magnitude (AB) from CFHTLS T0007 (3)
184-191 F8.4 mag iT07 ?=-99 i magnitude (AB) from CFHTLS T0007 (3)
193-200 F8.4 mag yT07 ?=-99 y magnitude (AB) from CFHTLS T0007 (3)
202-209 F8.4 mag zT07 ?=-99 z magnitude (AB) from CFHTLS T0007 (3)
211-218 F8.4 mag e_uT07 ?=-99 error on uT07 (3)
220-227 F8.4 mag e_gT07 ?=-99 error on gT07 (3)
229-236 F8.4 mag e_rT07 ?=-99 error on rT07 (3)
238-245 F8.4 mag e_iT07 ?=-99 error on iT07 (3)
247-254 F8.4 mag e_yT07 ?=-99 error on yT07 (3)
256-263 F8.4 mag e_zT07 ?=-99 error on zT07 (3)
265-272 F8.4 mag dUG ?=-99 Tile to tile color offset δUG (4)
274-281 F8.4 mag dGR ?=-99 Tile to tile color offset δGR (4)
283-290 F8.4 mag dRI ?=-99 Tile to tile color offset δRI (4)
292-298 F7.5 mag E(B-V) [0.01/0.05] Extinction factor E(B-V) derived
from Schlegel's (1998ApJ...500..525S 1998ApJ...500..525S) maps
300-307 F8.2 pix r2 Radius enclosing half the object light as
from CFHTLS T0005 catalogue
309-316 F8.2 pix r2T07 Radius enclosing half the object light as
from CFHTLS T0007 catalogue
318-320 I3 --- cl [-88/1]?=-99 VIPERS selection flag based on
the CFHTLS T0005 catalogue (see Guzzo et al.
1303.2623, Sect. 4) (classFlag)
322-324 I3 --- fa [-88/1]?=-99 A value equal to 1 is assigned to
all AGN candidates, and equal to 0 otherwise
(see Sect. 2.2) (agnFlag)
326 I1 --- fp [0/1] 1 = object inside photometric mask,
0 = object outside (photoMask)
328 I1 --- fs [0/1] 1 = object inside the spectroscopic mask,
0 = object outside (spectMask)
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Note (2): u,g,r,i,z magnitudes (AB system) from the CFHTLS T0005 catalogue,
supplemented by T0006 catalogue in some specific cases (see Guzzo et al.,
1303.2623, Sect. 3 and Appendix C, for details on the tile to tile color
offsets, as well as for T0005 and T0006 catalogue differences).
All magnitudes are corrected for Galactic extinction. When an object has not
been observed in a given band, magnitude and error are set equal to -99.
Note (3): Magnitudes (AB system) from the CFHTLS T0007 catalogue.
All magnitudes are corrected for Galactic extinction.
Note (4): Tile to tile color offsets used in the targets sample selection
applied to the CFHTLS T0005 data (see Guzzo et al., 1303.2623,
Sect. 3.1).
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Byte-by-byte Description of file: w1spdr1.dat w4spdr1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- --- [VIPERS]
8- 16 I9 --- VIPERS VIPERS number
18- 26 I9 --- Num Internal id number (G1)
28- 37 F10.6 deg RAdeg Right Ascension (J2000) (alpha)
39- 47 F9.6 deg DEdeg Declination (J2000) (delta)
49- 55 F7.4 mag imag AB selection (i-band) magnitude. The selection
magnitude comes from CFHTLS T0005 catalogues
57- 62 F6.4 mag e_imag Error on the selection magnitude (errselmag)
64- 69 A6 --- Point Pointing name
71 I1 --- Q [1/4] Quadrant
73- 77 F5.1 --- q_zsp [0/230] Redshift confidence flag (1)
79- 84 F6.4 --- zsp ?=9.9999 Spectroscopic redshift
86 I1 --- Ep [1/2] Observing epoch (2)
88 I1 --- fp [0/1] 1 = object inside photometric mask,
0 = object outside (photoMask)
90- 97 F8.4 --- TSR [-1/1]?=-99 Target sampling rate (3)
99-105 F7.3 --- SSR [-1/1]?=-99 Spectroscopic sampling rate (4)
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Note (1): as described in Sect. 4.3. It is in the form q.X, 2q.X, where:
* the decimal part (X) indicates concordance X≥4) or discordance
(X<3) with the photometric redshift.
* "q" is a quality flag for the spectrum; values >10 indicate an AGN.
The values are:
4 = a highly reliable redshift (estimated to have >95% probability of
being correct), based on a high SNR spectrum and supported by obvious
and consistent spectral features.
3 = also a very reliable redshift, comparable in confidence with Flag 4,
supported by clear spectral features in the spectrum, but not
necessarily with high SNR.
2 = a fairly reliable redshift measurement, but not as straightforward to
confirm as for Flags 3 and 4, supported by cross-correlation results,
continuum shape and some spectral features, with expected chance of
~=75% to be correct. We shall see in the following that the actual
estimated confidence level will turn out to be significantly better.
1 = a reasonable redshift measurement, based on weak spectral features
and/or continuum shape, for which there is roughly a 50% chance that
the redshift is actually wrong.
0 = no reliable spectroscopic redshift measurement was possible.
9 = a redshift based on only one single clear spectral emission feature.
10 = spectrum with clear problems in the observation or data processing
phases. It can be a failure in the vmmps Sky to CCD conversion
(especially at field corners), or a failed extraction by VIPGI
(Scodeggio et al. 2005PASP..117.1284S 2005PASP..117.1284S), or a bad sky subtraction
because the object is too close to the edge of the slit.
14 = secure AGN with a >95% reliable redshift, including at least 2
broad lines.
13 = secure AGN with good confidence redshift, based on one broad line
and some faint additional feature.
19 = secure AGN with one single secure emission line feature, redshift
based on this line only.
12 = a >95% reliable redshift measurement, but lines are not significantly
broad, might not be an AGN.
11 = a tentative redshift measurement, with spectral features not
significantly broad.
* "2" added in front of the number (i.e. adding 20 when q<10, or 200
for an AGN), indicates a serendipitous (also called secondary) object
appearing by chance within the slit of the main target.
Note (2): Observing epoch as follows:
1 = objects have been observed before VIMOS refurbishing in summer 2010
2 = objects have been observed after summer 2010
Note (3): the Target Sampling Rate, representing the fraction of the parent
sample for which a spectrum has been acquired, is described in Sect. 6.2.
Special values are:
-1 = serendipitous targets (confidence flag q_zsp of the form 2*.*),
and observed objects not fulfilling the selection criterion for
z>0.5 galaxies (i.e. AGN);
-99 = objects outside the considered area and selection magnitude range
(i.e. either i<17.5 or i>22.5).
Note (4): the Spectroscopic Success Rate, defined as the fraction of
measured candidate galaxy targets with a reliable redshift measurement
(confidence flag q_zsp of the form *[2349].*) is described in Sect. 6.3.
Special values are:
-1 = stars (z=0.0000), non measured objects (flag 0),
low confidence redshift measurements (flags 1.*),
spectroscopic broad-line AGNs (flags 1*.*),
serendipitous targets (flags 2*.*),
and high redshift galaxies (zspec>3);
-99 = objects outside the considered area and selection magnitude
range (i.e. either i<17.5 or i>22.5).
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Global notes:
Note (G1): Internal id number (num) in the form attxxxxxx where a identifies the
sky area (1 for W1 and 4 for W4), tt identifies the CFHTLS tile number where
the object is located, xxxxxx is the original CFHTLS ID within the tile.
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History:
Copied at http://vipers.inaf.it/
(End) Patricia Vannier [CDS] 08-Sep-2014