Terapix Star Formation Region IC 1396, © 2002 CFHT
UltraVISTA DR1 Photometric catalogues and photometric redshifts
by HJMCC HJMCC - Updated December 18th, 2014

If you use these catalogues presented here please reference the following papers:

For the photometric catalogue: McCracken et al. 2012, A&A, 544, 156 and Capak et al. 2007, ApJS, 172, 99

For the photometric redshifts and physical parameters: Ilbert et al. 2013, A&A, 556A, 55I (astro-ph/1301.3157)

You must also include the following standard acknowledgement:

"Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under ESO programme ID 179.A-2005 and on data products produced by TERAPIX and the Cambridge Astronomy Survey Unit on behalf of the UltraVISTA consortium."

This page describes the combined COSMOS and UltraVISTA DR1 photometric and photometric redshift catalogues. They correspond to the catalogues used in Ilbert et al. 2013 .

These photometric redshift catalogues are also available from the CDS .

These public catalogues have been assembled by combining data obtained at the ESO-VISTA telescope by the UltraVista collaboration, as processed at IAP-Terapix and made publicly available (McCracken et al., 2012), and from the imaging data publicly available from the COSMOS collaboration including HST, Subaru, CFHT, and Spitzer and distributed by IRSA . Photometric redshifts have been computed with Le Phare at LAM and have been calibrated using spectroscopic data obtained in the COSMOS fields as described in Ilbert et al. (2013).

DescriptionFilename
PSF homogenised photometric catalogueUVISTA_COSMOS_psfhomo_chi2_v1.1_22_04_13_v1.fits.gz
README file for the photometric catalogueUVISTA_COSMOS_psfhomo_chi2_v1.1_22_04_13_v1.fits.readme
Photometric redshiftsphotoz_uvista_v1.2.dat.gz
Probability distribution functions for each photometric redshiftpdz_uvista_v1.2.fits.gz
Description of columns in photometric redshift filesphotoz_uvista_v1.2.readme
DS9 region file outlining edges of Ks imagepolygon_UVISTA_Ks.reg
Mass function measurementsMFuvista_June13.tar.gz

Photometric redshifts, probability distribution functions and mass functions

These are described fully in Ilbert et al. 2013 . The probability distribution function file is described in its FITS header.

Photometric catalogues

This catalogue is a chisquared-selected source list comprising both COSMOS medium and narrow-band data and the UltraVISTA DR1 near-infrared data. The detection image was constructed from the chisquared sum of the Y, J, H and Ks UltraVISTA DR1 images. This ensures that the catalogue contains both redder and bluer objects (which would be missing from a simple Ks-selected catalogue. The production of this photometric catalogue is described fully in Ilbert et al. 2013 . Each near-infrared and optical band has been convolved so the final seeing (measured using a fit to a Moffat profile) corresponds to 1.1''.

The production of the near-infrared stacks used here, UltraVISTA DR1, is described in McCracken et al. 2012 .

In order to compute photometric redshifts with this catalogue, some additional corrections were applied to the magnitudes provided here. The most important of these consists of an offset of -0.369 which was applied to the B-band magnitudes, as has been applied to previous COSMOS catalogue.

Common parameters for each object

The photometric catalogue is delivered as a FITS table containing the parameters described below. A complete list of object parameters is given in the accompanying readme .

Parameter Description Units
ALPHA_J2000 Right ascension degrees
DELTA_J2000 Declination degrees
NUMBER Object ID none
X_IMAGE Object X-position in 0.15'' pixels pixels
Y_IMAGE Object Y-position in 0.15" pixels pixels
FLAG_HJMCC 0:good areas, >=1: masked in K pixels
FLUX_RADIUS Sextractor automatic aperture magnitudes pixels
EBV Extinction measured at the object position none
FLAG_PETER OR'ed flag constructed from COSMOS image masks non

Parameters for each individual band:

Each column name is constructed from joining the band name, the PSF status, and the parameter. For example, the PSF-homogenised Ks 2" aperture flux is given by: Ks_psf_MAG_APER2.

Parameter Description Units
_MAG_APER2 SExtractor 2" diameter aperture magnitudes AB magnitudes
_MAGERR_APER2 Error on SExtractor 2" diameter magnitudes AB magnitudes
_MAG_APER3 SExtractor 2" aperture diameter magnitudes AB magnitudes
_MAGERR_APER3 Error on SExtractor 3" aperture diameter magnitudes AB magnitudes
_MAG_AUTO SExtractor automatic Kron-like magnitudes AB magnitudes
_MAGERR_AUTO Error on SExtractor automatic Kron-like magnitudes AB magnitudes
_FLAGS SExtractor object extraction flags none
_IMAFLAGS_ISO Object flags indicating saturation none

The complete list of photometric broad-band provided is as follows: u,Bj,Vj, r+, i+, z+, zpp, Y, J, H, Ks. In addition there are also the Subaru medium-band filter data listed in Ilbert al 2013.

These bands appear in the catalogue with the suffix _psf to indicate that they have been PSF-homogenised. There is also the non-psf homogenised original Ks image. A MAG_AUTO selection (Ks < 24) on this column was used to produce the object catalogue for the accompanying mass function paper.

There are two subaru z+ bands here: the first corresponds to the "zp" presented in Capak et al. 2007; the second corresponds to much deeper z-band data acquired with newer red-sensitive CCDs recently installed at Subaru. Only the second, deeper zp data is used for the photometric redshift determination.


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