Weak lensing SOM-gold catalogue
The weak lensing SOM-gold catalogue is described in a series of papers. The source detection and photometry is presented in Kuijken, Heymans, Dvornik, Hildebrandt, de Jong, Wright, Erben et al 2019. The weak lensing measurement and systematics tests are presented in Giblin, Heymans, Asgari et al 2021. The SOM methodology for redshift calibration is presented in Wright et al. 2020. The KiDS-1000 redshift calibration is presented in Hildebrandt, van den Busch, Wright et al 2021.
This Cosmology Talk seminar summarises the main results.
Download the KiDS-1000 Catalogue
The KiDS-1000 data set encompasses 1006 survey tiles. Only galaxies with reliable shape and redshift measurements, our "gold sample", are included in this catalogue. The catalogue contains a total of 21,262,011 sources, and is presented as a single 16GB FITS table. It can be downloaded here.
You can also download an n(z) tarball containing SOM-calibrated redshift distributions for the 5 tomographic redshift bins used in the KiDS-1000 analysis.
Users of these data are asked to acknowledge us in any publications as indicated at the bottom of this page.
The table below lists the columns provided in the source catalogue.
| Column | Unit | Description | Format |
|---|---|---|---|
| SeqNr | Running object number within the catalogue | 1J | |
| SLID | AstroWise Source list ID | 1J | |
| SID | AstroWise Source ID within the source list | 1J | |
| ID | ESO ID | 25A | |
| FLUX_AUTO | count | r-band flux (count) | 1E |
| FLUXERR_AUTO | count | Error on FLUX_AUTO (count) | 1E |
| MAG_AUTO | mag | r-band magnitude (mag) | 1E |
| MAGERR_AUTO | mag | Error on MAG_AUTO (mag) | 1E |
| KRON_RADIUS | pixel | Scaling radius of the ellipse for magnitude measurements | 1E |
| BackGr | count | Background count at centroid position (count) | 1E |
| Level | count | Detection threshold above background (count) | 1E |
| MU_THRESHOLD | mag * arcsec**(-2) | Detection threshold above background (mag arcsec^-2) | 1E |
| MaxVal | count | Peak flux above background (count) | 1E |
| MU_MAX | mag * arcsec**(-2) | Peak surface brightness above background (mag arcsec^-2) | 1E |
| ISOAREA_WORLD | deg**2 | Isophotal area above analysis threshold (deg^2) | 1E |
| Xpos | pixel | Centroid x position in the THELI image (pix) | 1E |
| Ypos | pixel | Centroid y position in the THELI image (pix) | 1E |
| RAJ2000 | deg | Centroid sky position right ascension (J2000) (deg) | 1D |
| DECJ2000 | deg | Centroid sky position declination (J2000) (deg) | 1D |
| A_WORLD | deg | Profile RMS along major axis (deg) | 1E |
| B_WORLD | deg | Profile RMS along minor axis (deg) | 1E |
| THETA_J2000 | deg | Position angle (West of North) (deg) | 1E |
| THETA_WORLD | deg | Position angle (Counterclockwise from world x-axis (deg) | 1E |
| ERRA_WORLD | deg | World RMS position error along major axis (deg) | 1E |
| ERRB_WORLD | deg | World RMS position error along minor axis (deg) | 1E |
| ERRTHETA_J2000 | deg | Error on THETA_J2000 (deg) | 1E |
| ERRTHETA_WORLD | deg | Error on THETA_WORLD (deg) | 1E |
| FWHM_IMAGE | pixel | FWHM assuming a gaussian object profile (pix) | 1E |
| FWHM_WORLD | deg | FWHM assuming a gaussian object profile (deg) | 1E |
| Flag | SExtractor extraction flags | 1I | |
| FLUX_RADIUS | pixel | Half-light radius (pix) | 1E |
| CLASS_STAR | Star-galaxy classifier | 1E | |
| EXTINCTION_u | mag | Galactic extinction in the u band (mag) | 1E |
| EXTINCTION_g | mag | Galactic extinction in the g band (mag) | 1E |
| EXTINCTION_r | mag | Galactic extinctio in the r band (mag) | 1E |
| EXTINCTION_i | mag | Galactic extincion in the i band (mag) | 1E |
| PAgaap | deg | Position angle of major axis of GAaP aperture (North of West) (deg) | 1E |
| MAG_ISO | mag | r-band Isophotal Magnitude (mag) | 1E |
| MAGERR_ISO | mag | Error on MAG_ISO (mag) | 1E |
| FLUX_ISO | count | r-band Isophotal Flux (count) | 1E |
| FLUXERR_ISO | count | Error on FLUX_ISO (count) | 1E |
| MAG_ISOCOR | mag | r-band Corrected Isophotal Magnitude (mag) | 1E |
| MAGERR_ISOCOR | mag | Error on MAG_ISOCOR (mag) | 1E |
| FLUX_ISOCOR | count | r-band Corrected Isophotal Flux (count) | 1E |
| FLUXERR_ISOCOR | count | Error on FLUX_ISOCOR (count) | 1E |
| NIMAFLAGS_ISO | Number of flagged pixels over the isophotal profile | 1I | |
| IMAFLAGS_ISO | FLAG-image flags ORed over the isophotal profile | 1I | |
| XMIN_IMAGE | pixel | Minimum x-coordinate among detected pixels (pixel) | 1I |
| YMIN_IMAGE | pixel | Minimum y-coordinate among detected pixels (pixel) | 1I |
| XMAX_IMAGE | pixel | Maximum x-coordinate among detected pixels (pixel) | 1I |
| YMAX_IMAGE | pixel | Maximum x-coordinate among detected pixels (pixel) | 1I |
| X_WORLD | deg | Barycentre position along world x axis (deg) | 1D |
| Y_WORLD | deg | Barycentre position along world y axis (deg) | 1D |
| X2_WORLD | deg**2 | Variance of position along X_WORLD (alpha) (deg^2) | 1E |
| Y2_WORLD | deg**2 | Variance of position along X_WORLD (delta) (deg^2) | 1E |
| XY_WORLD | deg**2 | Covariance of position X_WORLD/Y_WORLD (deg^2) | 1E |
| ERRX2_WORLD | deg**2 | Error on XY_WORLD (deg^2) | 1E |
| ERRY2_WORLD | deg**2 | Error on XY_WORLD (deg^2) | 1E |
| ERRXY_WORLD | deg**2 | Error on XY_WORLD (deg^2) | 1E |
| CXX_WORLD | deg**(-2) | SExtractor Cxx object ellipse parameter (deg^-2) | 1E |
| CYY_WORLD | deg**(-2) | SExtractor Cyy object ellipse parameter (deg^-2) | 1E |
| CXY_WORLD | deg**(-2) | SExtractor Cxy object ellipse parameter (deg^-2) | 1E |
| ERRCXX_WORLD | deg**(-2) | Error on CXX_WORLD (deg^-2) | 1E |
| ERRCYY_WORLD | deg**(-2) | Error on CYY_WORLD (deg^-2) | 1E |
| ERRCXY_WORLD | deg**(-2) | Error on CXY_WORLD (deg^-2) | 1E |
| A_IMAGE | pixel | Profile RMS along x-axis (pix) | 1D |
| B_IMAGE | pixel | Profile RMS along y-axis (pix) | 1D |
| ERRA_IMAGE | pixel | Error on A_IMAGE | 1E |
| ERRB_IMAGE | pixel | Error on B_IMAGE | 1E |
| S_ELLIPTICITY | SExtractor Ellipticity (1-B_IMAGE/A_IMAGE) | 1E | |
| S_ELONGATION | SExtractor Elongation (A_IMAGE/B_IMAGE) | 1E | |
| ALPHA_J2000 | deg | SExtractor named Centroid sky position right ascension (J2000) (deg) | 1D |
| DELTA_J2000 | deg | SEXtractor named Centroid sky position declination (J2000) (deg) | 1D |
| SG2DPHOT | 2DPhot Star/Galaxy classifier (1 for high confidence star) | 1I | |
| HTM | Hierarchical Triangular Mesh (level 25) | 1J | |
| FIELD_POS | Reference number to field parameters | 1I | |
| EXTINCTION_Z | Galactic extinction in the Z band (mag) | 1E | |
| EXTINCTION_Y | Galactic extinction in the Y band (mag) | 1E | |
| EXTINCTION_J | Galactic extinction in the J band (mag) | 1E | |
| EXTINCTION_H | Galactic extinction in the H band (mag) | 1E | |
| EXTINCTION_Ks | Galactic extinction in the Ks band (mag) | 1E | |
| MAG_GAAP_u | mag | u-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_u | mag | u-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_u | count | u-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_u | count | u-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_u | GAaP Flag for MAG_GAAP_u optimal min_aper | 1I | |
| MAG_GAAP_g | mag | g-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_g | mag | g-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_g | count | g-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_g | count | g-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_g | GAaP Flag for MAG_GAAP_g optimal min_aper | 1I | |
| MAG_GAAP_r | mag | r-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_r | mag | r-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_r | count | r-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_r | count | r-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_r | GAaP Flag for MAG_GAAP_r optimal min_aper | 1I | |
| MAG_GAAP_i | mag | i-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_i | mag | i-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_i | count | i-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_i | count | i-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_i | GAaP Flag for MAG_GAAP_i optimal min_aper | 1I | |
| MAG_GAAP_Z | mag | Z-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_Z | mag | Z-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_Z | count | Z-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_Z | count | Z-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_Z | GAaP Flag for MAG_GAAP_Z optimal min_aper | 1I | |
| MAG_GAAP_Y | mag | Y-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_Y | mag | Y-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_Y | count | Y-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_Y | count | Y-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_Y | GAaP Flag for MAG_GAAP_Y optimal min_aper | 1I | |
| MAG_GAAP_J | mag | J-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_J | mag | J-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_J | count | J-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_J | count | J-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_J | GAaP Flag for MAG_GAAP_J optimal min_aper | 1I | |
| MAG_GAAP_H | mag | H-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_H | mag | H-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_H | count | H-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_H | count | H-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_H | GAaP Flag for MAG_GAAP_H optimal min_aper | 1I | |
| MAG_GAAP_Ks | mag | Ks-band GAaP magnitude optimal min_aper | 1E |
| MAGERR_GAAP_Ks | mag | Ks-band GAaP magnitude error optimal min_aper | 1E |
| FLUX_GAAP_Ks | count | Ks-band GAaP flux optimal min_aper | 1E |
| FLUXERR_GAAP_Ks | count | Ks-band GAaP flux error optimal min_aper | 1E |
| FLAG_GAAP_Ks | GAaP Flag for MAG_GAAP_Ks optimal min_aper | 1I | |
| Agaper | arcsec | Major axis of GAaP aperture optimal min_aper (arcsec) | 1E |
| Bgaper | arcsec | Minor axis of GAaP aperture optimal min_aper (arcsec) | 1E |
| MAG_LIM_u | mag | u-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_g | mag | g-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_r | mag | r-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_i | mag | i-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_Z | mag | Z-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_Y | mag | Y-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_J | mag | J-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_H | mag | H-band limiting magnitude optimal min_aper | 1E |
| MAG_LIM_Ks | mag | Ks-band limiting magnitude optimal min_aper | 1E |
| Z_B | 9-band BPZ redshift estimate; peak of posterior probability distribution | 1D | |
| Z_B_MIN | Lower bound of the 68% confidence interval of Z_B | 1D | |
| Z_B_MAX | Upper bound of the 68% confidence interval of Z_B | 1D | |
| T_B | Spectral type corresponding to Z_B | 1D | |
| ODDS | Empirical ODDS of Z_B | 1D | |
| Z_ML | 9-band BPZ maximum likelihood redshift | 1D | |
| T_ML | Spectral type corresponding to Z_ML | 1D | |
| CHI_SQUARED_BPZ | chi sqared value associated with Z_B | 1D | |
| M_0 | mag | Reference magnitude for BPZ prior | 1D |
| BPZ_FILT | filters with good photometry (BPZ) | 1J | |
| NBPZ_FILT | number of filters with good phot. (BPZ) | 1J | |
| BPZ_NONDETFILT | filters with faint photometry (BPZ) | 1J | |
| NBPZ_NONDETFILT | number of filters with faint phot. (BPZ) | 1J | |
| BPZ_FLAGFILT | flagged filters (BPZ) | 1J | |
| NBPZ_FLAGFILT | number of flagged filters (BPZ) | 1J | |
| SG_FLAG | Star/Gal Classifier | 1E | |
| MASK | 9-band mask information | 1J | |
| THELI_NAME | THELI name for the tile | 16A | |
| fitclass | fit class (=0 for galaxies) | 1I | |
| bias_corrected_scalelength_pixels | pix | galaxy model scale length | 1E |
| bulge_fraction | galaxy model bulge fraction | 1E | |
| model_flux | counts | galaxy model r-band flux | 1E |
| pixel_SNratio | SNR on the pixels | 1E | |
| model_SNratio | SNR for model fit | 1E | |
| contamination_radius | pix | Distance to nearest contaminating pixel | 1E |
| PSF_e1 | mean ellipticity of PSF, component 1 | 1E | |
| PSF_e2 | mean ellipticity of PSF, component 2 | 1E | |
| PSF_Strehl_ratio | Pseudo-Strehl ratio of PSF (flux fraction in central pixel) | 1E | |
| PSF_Q11 | model PSF moment Q11 | 1E | |
| PSF_Q22 | model PSF moment Q22 | 1E | |
| PSF_Q12 | model PSF moment Q12 | 1E | |
| star_galaxy_f_probability | Lensfit star/galaxy probability | 1E | |
| r_correction | Lensfit size correction | 1E | |
| 2D_measurement_variance | Lensfit measurement variance | 1E | |
| mean_likelihood_e | Lensfit mean likelihoo ellipticity | 1E | |
| neighbour_mag | mag | Lensfit neighbour magnitude | 1E |
| neighbour_distance | pix | Lensfit neighbour distance | 1E |
| catmag | mag | Lensfit input magnitude (same as MAG_AUTO) | 1E |
| n_exposures_used | Number of exposures used | 1E | |
| cat_ID | Lensfit used ID (same as SeqNr) | 1J | |
| delta_SNR | Lensift change in SNR between exposures - useful to detect asteroids | 1E | |
| PSF_e1_exp1 | PSF model ellipticity component 1 on exposure 1 | 1E | |
| PSF_e2_exp1 | PSF model ellipticity component 2 on exposure 1 | 1E | |
| PSF_e1_exp2 | PSF model ellipticity component 1 on exposure 2 | 1E | |
| PSF_e2_exp2 | PSF model ellipticity component 2 on exposure 2 | 1E | |
| PSF_e1_exp3 | PSF model ellipticity component 1 on exposure 3 | 1E | |
| PSF_e2_exp3 | PSF model ellipticity component 2 on exposure 3 | 1E | |
| PSF_e1_exp4 | PSF model ellipticity component 1 on exposure 4 | 1E | |
| PSF_e2_exp4 | PSF model ellipticity component 2 on exposure 4 | 1E | |
| PSF_e1_exp5 | PSF model ellipticity component 1 on exposure 5 | 1E | |
| PSF_e2_exp5 | PSF model ellipticity component 2 on exposure 5 | 1E | |
| SeqNr_field | SeqNr in THELI_NAME | 1J | |
| THELI_INT | Integer identifier for KiDS tile (unique in KiDS-N and KiDS-S each) | 1I | |
| e1 | Lensfit ellipticity e1 - no m or c corr | 1E | |
| e2 | Lensfit ellipticity e2 - no m or c corr | 1E | |
| weight | Recalibrated Lensfit inverse variance weight | 1E |
Acknowledgment
We welcome independent analyses of the KiDS-1000 data products, provided that KiDS is acknowledged in any resulting publications. Users of these data are required to include the following statement in their paper:
Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme IDs 177.A-3016, 177.A-3017, 177.A-3018 and 179.A-2004, and on data products produced by the KiDS consortium. The KiDS production team acknowledges support from: Deutsche Forschungsgemeinschaft, ERC, NOVA and NWO-M grants; Target; the University of Padova, and the University Federico II (Naples).
Additionally, any publications should cite the relevant KiDS-1000 papers as follows:
We use the gold sample of weak lensing and photometric redshift measurements from the fourth data release of the Kilo-Degree Survey (Kuijken et al. 2019, Wright et al. 2020, Hildebrandt et al. 2021, Giblin et al 2021), hereafter referred to as KiDS-1000. Cosmological parameter constraints from KiDS-1000 have been presented in Asgari et al 2021 (cosmic shear), Heymans et al 2021 (3x2pt) and Tröster et al 2021 (beyond ΛCDM), with the methodology presented in Joachimi et al 2021.