pith. machine review for the scientific record. sign in

arxiv: astro-ph/0603217 · v1 · submitted 2006-03-09 · 🌌 astro-ph

Recognition: unknown

Accurate photometric redshifts for the CFHT Legacy Survey calibrated using the VIMOS VLT Deep Survey

Authors on Pith no claims yet
classification 🌌 astro-ph
keywords photometricredshiftssampledeepsurveyredshiftspectroscopiccatastrophic
0
0 comments X
read the original abstract

We present photometric redshifts for an uniquely large and deep sample of 522286 objects with i'_{AB}<25 in the Canada-France Legacy Survey ``Deep Survey'' fields, which cover a total effective area of 3.2 deg^2. We use 3241 spectroscopic redshifts with 0<z<5 from the VIMOS VLT Deep Survey as a calibration to derive these photometric redshifts. We devise a robust calibration method which removes systematic trends in the photometric redshifts and significantly reduces the fraction of catastrophic errors. We use our unique spectroscopic sample to present a detailed assessment of the robustness of the photometric redshift sample. For a sample selected at i'_{AB}<24, we reach a redshift accuracy of \sigma_{\Delta z/(1+z)}=0.037 with \eta=3.7% of catastrophic error. The reliability of our photometric redshifts is lower for fainter objects: we find \sigma_{\Delta z/(1+z)}=0.029, 0.043 and \eta=1.7%, 5.4% for samples selected at i'_{AB}=17.5-22.5 and 22.5-24 respectively. We find that the photometric redshifts of starburst galaxies in our sample are less reliable: although these galaxies represent only 18% of the spectroscopic sample they are responsible for 54% of the catastrophic errors. We find an excellent agreement between the photometric and the VVDS spectroscopic redshift distributions at i'_{AB}<24. Finally, we compare the redshift distributions of i' selected galaxies on the four CFHTLS deep fields, showing that cosmic variance is already present on fields of 0.8 deg^2.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 11 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Galaxy Zoo Bar Lengths: A Catalogue of Measurements from Hubble Space Telescope Images and the Evolution of Galactic Bar Structure at z < 1

    astro-ph.GA 2026-04 conditional novelty 7.0

    A new catalogue of bar lengths and widths from HST images of 8230 galaxies shows bars are about 13% weaker at higher redshift, with longer bars in higher-mass quiescent galaxies and trends consistent with slow quenching.

  2. Empirical estimates of how massive galaxies can be in {\Lambda}CDM

    astro-ph.GA 2026-05 conditional novelty 6.0

    Corrected empirical limits show the most massive galaxies never exceed the theoretical baryonic maximum of 0.16 times halo virial mass, keeping observations consistent with LambdaCDM at all redshifts.

  3. Euclid preparation. CosmoPostProcess: A simulation calibrated framework for weak lensing selection bias in richness-selected galaxy clusters

    astro-ph.CO 2026-05 unverdicted novelty 6.0

    CosmoPostProcess delivers simulation-calibrated radial corrections for projection-induced selection bias (20-40% amplitude near 1 h^{-1} Mpc) and baryonic effects in Euclid richness-selected cluster weak lensing profiles.

  4. Empirical estimates of how massive galaxies can be in {\Lambda}CDM

    astro-ph.GA 2026-05 unverdicted novelty 5.0

    Empirical upper limits on galaxy stellar masses from extreme value statistics, after correcting for Eddington bias and halo mass scatter, remain below the theoretical baryonic maximum of 0.16 times halo mass at all re...

  5. The Evolution of the SFR-M_* relation at 0.1<z<4: Environmental and Morphological Dependencies

    astro-ph.GA 2026-04 unverdicted novelty 5.0

    The SFR-M_* relation develops a high-mass decline at low redshifts, driven mainly by morphological quenching from internal structure rather than environmental effects on star-forming galaxies.

  6. A Catalog of Mid-infrared Variable Sources in the Ecliptic Poles

    astro-ph.GA 2026-04 unverdicted novelty 5.0

    New catalog identifies 30,345 mid-IR variable sources at ecliptic poles from NEOWISE data, with AGN dominating in the north and stars in the south plus three transients linked to obscured QSOs.

  7. The Pantheon+ Analysis: The Full Dataset and Light-Curve Release

    astro-ph.CO 2021-12 accept novelty 5.0

    Pantheon+ releases 1701 light curves from 1550 spectroscopically confirmed Type Ia supernovae across 18 surveys for cosmological inference.

  8. Identification of Compact Groups of Galaxies in IllustrisTNG300

    astro-ph.GA 2026-05 unverdicted novelty 4.0

    Compact galaxy groups identified in TNG300 show that ~80% of velocity-selected groups are line-of-sight interlopers, with a stellar-mass versus velocity-dispersion scaling relation serving as an effective diagnostic.

  9. Validating z > 7.5 Lyman Break Galaxy candidates in the COSMOS field with JWST/PASSAGE

    astro-ph.GA 2026-05 conditional novelty 4.0

    Spectroscopic confirmation of one luminous z=7.96 Lyman break galaxy in a 4.8 arcmin² COSMOS field implies a surface density of 0.21 arcmin⁻², about 10 times higher than wide-area surveys and hinting at a z~8 overdensity.

  10. The NIKA2 Cosmological Legacy Survey in COSMOS: Final 1.2mm and 2mm source catalogs and redshift distribution of dusty star-forming galaxies

    astro-ph.GA 2026-05 accept novelty 4.0

    The NIKA2 survey delivers catalogs of 323 mm-selected sources in COSMOS with redshifts peaking at z=2.8, including 66 at z>4, matching SIDES simulations but inconsistent with four other galaxy evolution models.

  11. A Rare Eddington-Limited, Heavily Obscured Low-Mass Active Galactic Nucleus Likely Triggered by a Galaxy Merger

    astro-ph.GA 2026-04 unverdicted novelty 3.0

    GAMA 376183 is a rare Eddington-limited heavily obscured AGN in a merging low-mass galaxy, triggered by the merger and identified via strong [Ne V] emission.