### arXiv:xxxx.xxxxx LSST photo-z testbed catalogs (Zhou+, 2019) ================================================================================ Deep ugrizY Imaging and DEEP2/3 Spectroscopy: A Photometric Redshift Testbed for LSST and Public Release of Data from the DEEP3 Galaxy Redshift Survey Rongpu Zhou, Michael C. Cooper, Jeffrey A. Newman, Matthew L. N. Ashby, James Aird, Christopher J. Conselice, Marc Davis, Aaron A. Dutton, S. M. Faber, Jerome J. Fang, G. G. Fazio, Puragra Guhathakurta, Dale Kocevski, David C. Koo, Kirpal Nandra, Andrew C. Phillips, David J. Rosario, Edward F. Schlafly, Jonathan R. Trump, Benjamin Weiner, Christopher N. A. Willmer, and Renbin Yan ================================================================================ Keywords: galaxies: distances and redshifts – catalogues – surveys Abstract: We present catalogs of calibrated photometry and spectroscopic redshifts in the Extended Groth Strip, intended for studies of photometric redshifts (photo-z's). The data includes ugriz photometry from CFHTLS and Y-band photometry from the Subaru Suprime camera, as well as spectroscopic redshifts from the DEEP2, DEEP3 and 3D-HST surveys. These catalogs incorporate corrections to produce effectively matched-aperture photometry across all bands, based upon object size information available in the catalog and Moffat profile point spread function fits. We test this catalog with a simple machine learning-based photometric redshift algorithm, based upon Random Forest regression, and find that the corrected aperture photometry leads to significant improvement in photo-z accuracy compared to the original SExtractor catalogs from CFHTLS and Subaru. The deep ugrizY photometry and spectroscopic redshifts are well-suited for empirical tests of photometric redshift algorithms for LSST. We include a basic summary of the strategy of the DEEP3 Galaxy Redshift Survey to accompany the recent public release of DEEP3 data. File Summary: -------------------------------------------------------------------------------- FileName Records Explanations -------------------------------------------------------------------------------- ReadMe . This file DEEP2_uniq_Terapix_Subaru_v1.fits 23822 DEEP2/3 redshift catalog with CFHTLS Deep+Wide field ugriz photometry and Subaru Y-band photometry added 3D-HST_Terapix_Subaru_v1.fits 14462 3D-HST redshift catalog with CFHTLS Deep+Wide field ugriz photometry and Subaru Y-band photometry added; DEEP2 redshifts also added DEEP2_uniq_Terapix_Wide_Subaru_v1.fits 23822 DEEP2/3 redshift catalog with CFHTLS Wide field ugriz photometry and Subaru Y-band photometry added 3D-HST_Terapix_Wide_Subaru_v1.fits 14462 3D-HST redshift catalog with CFHTLS Wide field ugriz photometry and Subaru Y-band photometry added; DEEP2 redshifts also added Terapix_Deep_v1.fits 603852 CFHTLS Deep field catalog with ugriz photometry Terapix_Wide_combined_v1.fits 1415859 CFHTLS Wide field catalog with ugriz photometry Subaru_Y_v1.fits 94014 Subaru Y-band catalog -------------------------------------------------------------------------------- Description of file: DEEP2_uniq_Terapix_Subaru_v1.fits -------------------------------------------------------------------------------- Label Format Explanations -------------------------------------------------------------------------------- ## DEEP2/3 columns: objno_deep2 int32 DEEP2 object number ra_deep2 float64 Right Ascension from DEEP2 (in decimal degrees, J2000) dec_deep2 float64 Declination from DEEP2 (in decimal degrees, J2000) magb float32 CFHT B-band magnitude (AB) from Coil et al. 2004 magr float32 CFHT R-band magnitude (AB) from Coil et al. 2004 magi float32 CFHT I-band magnitude (AB) from Coil et al. 2004 pgal float32 the probability (0 - 1) that the sources is a galaxy for unresolved galaxies, 3 if resolved sfd_ebv float32 E(B-V) from Schlegel, Finkbeiner, and Davis dust map class string type of best-fitting template (e.g., GALAXY or STAR) subclass string coarse classification for stellar templates objname string the 8-digit DEEP2 object id (same as OBJNO) maskname string the DEEP2/DEEP3 slitmask number on which the object was observed slitname string the slitlet number (on mask MASKNAME) in which the object was placed date string Date on which the mask was observed (YYYY-MM-DD) mjd float32 Modified Julian date of observation z_raw float32 observed best-fitting redshift zhelio float32 redshift corrected for heliocentric motion z_err float32 redshift error rchi2 float32 reduced chi-squared value for the redshift fit dof int32 degrees of freedom for redshift fit vdisp float32 velocity dispersion in km/s vdisp_err float32 error in velocity dispersion zquality int16 redshift quality code, Q egsflags int32 flag denoting membership in a particular target list comment string comment field m_b float32 absolute B-band magnitude (AB, h = 1) from Willmer et al. (2006) ub_0 float32 rest-frame U-B color (AB) from Willmer et al. (2006) ## CFHTLS columns: ra_cfhtls float64 Right Ascension from CFHTLS after astrometric correction in decimal degrees dec_cfhtls float64 Declination from CFHTLS after astrometric correction in decimal degrees u float64 MAG_AUTO magnitude in u-band g float64 MAG_AUTO magnitude in g-band r float64 MAG_AUTO magnitude in r-band i float64 MAG_AUTO magnitude in i-band i2 float64 MAG_AUTO magnitude in i2-band z float64 MAG_AUTO magnitude in z-band uerr float64 MAG_AUTO magnitude error in u-band gerr float64 MAG_AUTO magnitude error in g-band rerr float64 MAG_AUTO magnitude error in r-band ierr float64 MAG_AUTO magnitude error in i-band i2err float64 MAG_AUTO magnitude error in i2-band zerr float64 MAG_AUTO magnitude error in z-band u_apercor float64 MAG_APERCOR magnitude in u-band g_apercor float64 MAG_APERCOR magnitude in g-band r_apercor float64 MAG_APERCOR magnitude in r-band i_apercor float64 MAG_APERCOR magnitude in i-band i2_apercor float64 MAG_APERCOR magnitude in i2-band z_apercor float64 MAG_APERCOR magnitude in z-band uerr_aper float64 MAG_APERCOR magnitude error from image noise in u-band gerr_aper float64 MAG_APERCOR magnitude error from image noise in g-band rerr_aper float64 MAG_APERCOR magnitude error from image noise in r-band ierr_aper float64 MAG_APERCOR magnitude error from image noise in i-band i2err_aper float64 MAG_APERCOR magnitude error from image noise in i2-band zerr_aper float64 MAG_APERCOR magnitude error from image noise in z-band uerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in u-band gerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in g-band rerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in r-band ierr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in i-band i2err_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in i2-band zerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in z-band r_radius_arcsec float64 r-band half-light radius in arcsec u(sexflag) int64 u-band SExtractor flag g(sexflag) int64 g-band SExtractor flag r(sexflag) int64 r-band SExtractor flag i(sexflag) int64 i-band SExtractor flag i2(sexflag) int64 i2-band SExtractor flag z(sexflag) int64 z-band SExtractor flag flag_cfhtls int64 CFHTLS flag cfhtls_source int64 source of the ugri(i2)z photometry: 0 = Deep field; 1 = Wide field; -99 = not observed ## Subaru Y-band columns: ra_subaru float64 Right Ascension from Subaru Y-band observation after astrometric correction in decimal degrees dec_subaru float64 Declination from Subaru Y-band observation after astrometric correction in decimal degrees y float64 MAG_AUTO magnitude in Subaru Y-band yerr float64 MAG_AUTO magnitude error in Subaru Y-band y_apercor float64 MAG_APERCOR magnitude in Y-band yerr_aper float64 MAG_APERCOR magnitude error from image noise in Y-band yerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in Y-band y(sexflag) float64 Y-band SExtractor flag y_radius_arcsec float64 Y-band half-light radius in arcsec subaru_source int64 source of the Y-band photometry: 0 = deep pointing; 1 = shallow pointing; -99 = not observed -------------------------------------------------------------------------------- Note (1): The CFHTLS ugriz and Subaru Y-band magnitudes have been corrected for Galacted extinction (2): If both CFHTLS Deep and Wide are available, the Deep field data is used (3): The catalog structure is based on alldeep.egs.uniq.2012jun13.fits.gz from http://deep.ps.uci.edu/deep3/zcatalog.html, with all the original DEEP2/3 objects and values kept unchanged (4): DEEP2_uniq_Terapix_Wide_Subaru_v1.fits only differs from this catalog in that it only includes CFHTLS Wide field data (5): More info on DEEP2/3: http://deep.ps.uci.edu/deep3/ztags.html (6): More info on CFHTLS: http://terapix.calet.org/terapix.iap.fr/cplt/T0007/doc/T0007-docsu22.html -------------------------------------------------------------------------------- Description of file: 3D-HST_Terapix_Subaru_v1.fits -------------------------------------------------------------------------------- Label Format Explanations -------------------------------------------------------------------------------- ## 3D-HST columns: ra_3dhst float64 Right Ascension from 3D-HST dec_3dhst float64 Declination from 3D-HST phot_id int64 Photometric id from Skelton et al. (2014) grism_id string Grism id of the spectrum which yielded this fit jh_mag float64 MAG_AUTO measured from the combined F125W+F140W+F160W image z_spec float64 Spectroscopic redshift where available (-1 if not available) z_peak_phot float64 Photometric redshift from Skelton et al. (2014) z_phot_l95 float64 Photometric redshift at the lower 95% confidence limit z_phot_l68 float64 Photometric redshift at the lower 68% confidence limit z_phot_u68 float64 Photometric redshift at the upper 68% confidence limit z_phot_u95 float64 Photometric redshift at the upper 95% confidence limit z_max_grism float64 Default grism redshift: the redshift where the p(z | grism, phot) is maximized z_peak_grism float64 Integral of p(z | grism, phot)*z*dz, integrated over the whole redshift range z_grism_l95 float64 Grism redshift at the lower 95% confidence limit z_grism_l68 float64 Grism redshift at the lower 68% confidence limit z_grism_u68 float64 Grism redshift at the upper 68% confidence limit z_grism_u95 float64 Grism redshift at the lower 95% confidence limit f_cover float64 Fraction of spectrum within the image (0=bad, 1=good) f_flagged float64 Fraction of flagged pixels (1=bad, 0=good) max_contam float64 Maximum contamination int_contam float64 Contamination integrated over the spectrum (= flux_contam/flux_object) f_negative float64 Fraction of pixels with negative flux after contamination correction flag1 int64 Grism z flag (user 1): -1=no flag, 0=good, 1=bad, 2=unclear flag2 int64 Grism z flag (user 2): -1=no flag, 0=good, 1=bad, 2=unclear use_zgrism int64 Flag defining objects with the most reliable grism-derived redshifts: 1=use, 0=do not use use_phot int64 Photometric use flag from Skelton et al. (2014): 1 = use; 0 = do not use z_best_s int64 Source of the best redshift: 1 = ground-based spectroscopy; 2 = grism; 3 = photometry; 0 = star z_best float64 Best available redshift measurement (-1 for stars) z_best_l95 float64 Lower 95% confidence limit derived form the z_best p(z), -1 for stars and z_spec z_best_l68 float64 Lower 68% confidence limit derived form the z_best p(z), -1 for stars and z_spec z_best_u68 float64 Upper 95% confidence limit derived form the z_best p(z), -1 for stars and z_spec z_best_u95 float64 Upper 95% confidence limit derived form the z_best p(z), -1 for stars and z_spec ## CFHTLS columns: ra_cfhtls float64 Right Ascension from CFHTLS after astrometric correction in decimal degrees dec_cfhtls float64 Declination from CFHTLS after astrometric correction in decimal degrees u float64 MAG_AUTO magnitude in u-band g float64 MAG_AUTO magnitude in g-band r float64 MAG_AUTO magnitude in r-band i float64 MAG_AUTO magnitude in i-band i2 float64 MAG_AUTO magnitude in i2-band z float64 MAG_AUTO magnitude in z-band uerr float64 MAG_AUTO magnitude error in u-band gerr float64 MAG_AUTO magnitude error in g-band rerr float64 MAG_AUTO magnitude error in r-band ierr float64 MAG_AUTO magnitude error in i-band i2err float64 MAG_AUTO magnitude error in i2-band zerr float64 MAG_AUTO magnitude error in z-band u_apercor float64 MAG_APERCOR magnitude in u-band g_apercor float64 MAG_APERCOR magnitude in g-band r_apercor float64 MAG_APERCOR magnitude in r-band i_apercor float64 MAG_APERCOR magnitude in i-band i2_apercor float64 MAG_APERCOR magnitude in i2-band z_apercor float64 MAG_APERCOR magnitude in z-band uerr_aper float64 MAG_APERCOR magnitude error from image noise in u-band gerr_aper float64 MAG_APERCOR magnitude error from image noise in g-band rerr_aper float64 MAG_APERCOR magnitude error from image noise in r-band ierr_aper float64 MAG_APERCOR magnitude error from image noise in i-band i2err_aper float64 MAG_APERCOR magnitude error from image noise in i2-band zerr_aper float64 MAG_APERCOR magnitude error from image noise in z-band uerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in u-band gerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in g-band rerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in r-band ierr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in i-band i2err_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in i2-band zerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in z-band r_radius_arcsec float64 r-band half-light radius in arcsec u(sexflag) int64 u-band SExtractor flag g(sexflag) int64 g-band SExtractor flag r(sexflag) int64 r-band SExtractor flag i(sexflag) int64 i-band SExtractor flag i2(sexflag) int64 i2-band SExtractor flag z(sexflag) int64 z-band SExtractor flag flag_cfhtls int64 CFHTLS flag cfhtls_source int64 source of the ugri(i2)z photometry: 0 = Deep field; 1 = Wide field; -99 = not observed ## Subaru Y-band columns: ra_subaru float64 Right Ascension from Subaru Y-band observation after astrometric correction in decimal degrees dec_subaru float64 Declination from Subaru Y-band observation after astrometric correction in decimal degrees y float64 MAG_AUTO magnitude in Subaru Y-band yerr float64 MAG_AUTO magnitude error in Subaru Y-band y_apercor float64 MAG_APERCOR magnitude in Y-band yerr_aper float64 MAG_APERCOR magnitude error from image noise in Y-band yerr_apercor float64 MAG_APERCOR magnitude error from correction uncertainty in Y-band y(sexflag) float64 Y-band SExtractor flag y_radius_arcsec float64 Y-band half-light radius in arcsec subaru_source int64 source of the Y-band photometry: 0 = deep pointing; 1 = shallow pointing; -99 = not observed ## DEEP2/3 columns: objno_deep2 int32 DEEP2/3 object number z_deep2 float32 DEEP2/3 redshift corrected for heliocentric motion z_err_deep2 float32 DEEP2/3 redshift error zquality_deep2 int16 DEEP2/3 redshift quality code, Q ## Other columns: use_zgrism1 int64 our grism redshift quality flag: 0 = less accurate; 1 = accurate sfd_ebv float64 E(B-V) from Schlegel, Finkbeiner, and Davis (1998) dust map -------------------------------------------------------------------------------- Note (1): The CFHTLS ugriz and Subaru Y-band magnitudes have been corrected for Galacted extinction (2): If both CFHTLS Deep and Wide are available, the Deep field data is used (3): The catalog structure is based on aegis_3dhst.v4.1.5.zfit.linematched.fits (RA and Dec are from aegis_3dhst.v4.1.cat.FITS) from https://3dhst.research.yale.edu/Data.php; Only objects with z_max_grism>0 AND z_peak_phot>0 are kept (4): 3D-HST_Terapix_Wide_Subaru_v1.fits only differs from this catalog in that it only includes CFHTLS Wide field data (5): More info on 3D-HST: http://monoceros.astro.yale.edu/RELEASE_V4.1.5/3dhst_readme_v4.1.5.pdf (6): More info on CFHTLS: http://terapix.calet.org/terapix.iap.fr/cplt/T0007/doc/T0007-docsu22.html -------------------------------------------------------------------------------- Terapix_Deep_v1.fits and Terapix_Wide_combined_v1.fits are CFHTLS catalogs with MAG_APERCOR added in the CFTHSL Deep field and Wide field, respectively. Photometric zero-point corrections are made and the magnitude columns are overwritten with the corrected values. There is no Galactic extinction correction. -------------------------------------------------------------------------------- Subaru_Y_v1.fits is the Subaru Y-band catalog from SExtractor with MAG_APERCOR added. Photometric zero-point corrections are made and the magnitude columns are overwritten with the corrected values. There is no Galactic extinction correction. ================================================================================ (End) Rongpu Zhou [University of Pittsburgh, USA] 2019/03/13