DR3 Data Page

The UDS DR3 was released to the world community in June 2009, and is based on data taken in the first two years of the UKIDSS project (2005 and 2006). The 5σ depths are J=23.7, H=23.5 and K=23.7 (AB). The aim of this page is provide an easy access point for the infrared images, catalogues and a range of additional data products. Details of additional multiwavelength data and spectroscopy can be found on the main UDS data page.

Image Data - full resolution

  • Full field, K-band (2.5Gb) FITS
  • Full field, K-band weight map (2.5Gb) FITS
  • Full field, H-band (2.5Gb) FITS
  • Full field, H-band weight map (2.5Gb) FITS
  • Full field, J-band (2.5Gb) FITS
  • Full field, J-band weight map (2.5Gb) FITS

NB: Pixel scale is 0.1342 arcsec. Zero points = 30.0 in each case (Vega).

Image Data - 2x2 binned

  • Full field, K-band (2.5Gb) FITS
  • Full field, K-band weight map (632Mb) FITS
  • Full field, H-band (632Mb) FITS
  • Full field, H-band weight map (632Mb) FITS
  • Full field, J-band (632Mb) FITS
  • Full field, J-band weight map (632Mb) FITS

NB: These images have been binned (2x2) to enable you to view and manipulate the full mosaic more easily on a 32bit machine or using IRAF. These oversample the psf and are suitable for essentially all scientific purposes. The pixel scale is 0.2684 arcsec. Zero points = 30.0 in each case (Vega).

J, H, K catalogues

The catalogues below were obtained by running Sextractor in two modes and combining the results, with one detection kernel designed to optimize deblending and the other optimized for extended faint sources. These catalogues were produced by Sebastien Foucaud. Catalogues were extracted using the K-band as the primary image, with J and H data extracted in dual image mode. Note that the catalogues below differ somewhat from the official catalogues in the WFCAM Science Archive, which were produced using a single set of Sextractor parameters.

These catalogues are in Vega units. To convert to AB use the conversions from Hewett et al. 2006.

Subaru optical images (B, V, R, i', z')

Subaru imaging of this field consists of 5 overlapping pointings with Suprimecam. Full details are given in Furusawa et al. 2008. Images, catalogues and zero-point information are available from the SXDS DR1 release page. The typical 3σ (AB) depths are B=28.4, V=27.8, R=27.7, i'=27.7, z'=26.7. Mosaics resampled to match the pixel scale and astrometric frame of the J,H,K images can be obtained here courtesy of Michele Cirasuolo.

UDS/Subaru matched catalogue (Simpson et al. 2010)

The catalogue below is based on a match between the UDS DR3+ K-band catalogue and images in B, V, R, i', z', J, H (i.e. primary object detection is in the K-band). The optical match was performed by Chris Simpson using the method outlined here. Full details will be published in Simpson et al. (2010, in prep).

  • Description of catalogue flags

Note: J,H,K magnitudes are given in both Vega and AB systems. Subaru B, V, R, i', z' magnitudes are all in AB units.

Photometric redshifts

A photometric-redshift catalogue based on the UDS DR3 data has been produced by Michele Cirasuolo, as outlined in Cirasuolo et al. 2007 . Please contact Michele directly to negotiate access.

Alternatively, photometric redshifts based on the DR1 data are available from the work of Williams et al. 2008

Spectroscopic redshifts

For details of available spectroscopic redshifts see the main UDS Data Page

Known Problems

The UDS DR3 images suffered significant large-scale correlated noise, mainly due to image remnance and sky variations during the course of the WFCAM dither sequence. The worst of these effects were removed in later data releases using improved sky subtraction and quality control. Bright objects also produce cross-talk patterns, as described part-way down this page.

Other useful information

  • WFCAM filter response curves.
  • Subaru filter response curves.
  • CFHT filter response curves.