DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The impact of spectroscopic incompleteness in direct calibration of redshift distributions for weak lensing surveys

Journal Article · · Monthly Notices of the Royal Astronomical Society
 [1]; ORCiD logo [2];  [3];  [4];  [5];  [6];  [7];  [4];  [8];  [9];  [10];  [5];  [11];  [7];  [12];  [5];  [3];  [13];  [14];  [15] more »;  [15];  [16];  [17];  [18];  [19];  [3];  [20];  [21];  [22];  [23];  [24];  [25];  [8];  [26];  [15];  [27];  [15];  [23];  [28];  [16];  [23];  [29];  [21];  [15];  [30];  [31];  [32];  [33];  [34];  [15];  [3];  [35];  [8];  [36];  [37];  [21];  [38];  [8];  [33];  [21];  [37];  [20];  [20];  [4];  [15];  [39];  [23];  [4];  [40];  [41];  [42];  [22];  [43];  [15];  [6];  [6];  [44] « less
  1. Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UK;Département de Physique Théorique and Center for Astroparticle Physics, Université de Genève, 24 quai Ernest Ansermet, CH-1211 Geneva, Switzerland;Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 16, CH-8093 Zurich, Switzerland
  2. Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637, USA;Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USA
  3. Department of Physics & Astronomy, University College London, Gower Street, London WC1E 6BT, UK
  4. Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, 28040, Spain
  5. School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072, Australia
  6. Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching, Germany;Fakultät für Physik, Universitäts-Sternwarte, Ludwig-Maximilians Universität München, Scheinerstr. 1, D-81679 München, Germany
  7. Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305, USA;Kavli Institute for Particle Astrophysics & Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA;SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
  8. Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ - 20921-400, Brazil;Observatório Nacional, Rua Gal. José Cristino 77, Rio de Janeiro, RJ - 20921-400, Brazil
  9. The Research School of Astronomy and Astrophysics, Australian National University, ACT 2601, Australia
  10. Australian Astronomical Optics, Macquarie University, North Ryde, NSW 2113, Australia;Lowell Observatory, 1400 Mars Hill Rd, Flagstaff, AZ 86001, USA
  11. McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
  12. Department of Astronomy, University of California, Berkeley, 501 Campbell Hall, Berkeley, CA 94720, USA;Santa Cruz Institute for Particle Physics, Santa Cruz, CA 95064, USA
  13. Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena, Chile
  14. Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ - 20921-400, Brazil;Departamento de Física Matemática, Instituto de Física, Universidade de São Paulo, CP 66318, São Paulo, SP, 05314-970, Brazil
  15. Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA
  16. Instituto de Fisica Teorica UAM/CSIC, Universidad Autonoma de Madrid, E-28049 Madrid, Spain
  17. Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
  18. CNRS, UMR 7095, Institut d’Astrophysique de Paris, F-75014 Paris, France;Institut d’Astrophysique de Paris, Sorbonne Universités, UPMC Univ Paris 06, UMR 7095, F-75014 Paris, France
  19. Jodrell Bank Center for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK
  20. Kavli Institute for Particle Astrophysics & Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA;SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
  21. Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, IL 61801, USA;National Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801, USA
  22. Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Campus UAB, E-08193 Bellaterra (Barcelona), Spain
  23. Institut d’Estudis Espacials de Catalunya (IEEC), E-08034 Barcelona, Spain;Institute of Space Sciences (ICE, CSIC), Campus UAB, Carrer de Can Magrans, s/n, E-08193 Barcelona, Spain
  24. Department of Physics, 2320 Chamberlin Hall, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706-1390, USA
  25. INAF-Osservatorio Astronomico di Trieste, via G. B. Tiepolo 11, I-34143 Trieste, Italy;Institute for Fundamental Physics of the Universe, Via Beirut 2, I-34014 Trieste, Italy
  26. Department of Physics, IIT Hyderabad, Kandi, Telangana 502285, India
  27. Faculty of Physics, Ludwig-Maximilians-Universität, Scheinerstr 1, D-81679 Munich, Germany
  28. Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USA;Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA
  29. Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA;Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA
  30. Santa Cruz Institute for Particle Physics, Santa Cruz, CA 95064, USA
  31. Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, OH 43210, USA;Department of Physics, The Ohio State University, Columbus, OH 43210, USA
  32. Center for Astrophysics |Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA
  33. Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA;Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USA
  34. Department of Astronomy/Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065, USA
  35. Departamento de Física Matemática, Instituto de Física, Universidade de São Paulo, CP 66318, São Paulo, SP, 05314-970, Brazil;Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ - 20921-400, Brazil
  36. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, and Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843, USA
  37. Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544, USA
  38. Australian Astronomical Optics, Macquarie University, North Ryde, NSW 2113, Australia;Institució Catalana de Recerca i Estudis Avançats, E-08010 Barcelona, Spain
  39. Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA
  40. School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK
  41. Department of Physics, Brandeis University,415 South Street, Waltham MA 02453, USA
  42. Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
  43. Department of Physics, Duke University Durham, NC 27708, USA
  44. Department of Physics and Astronomy, Pevensey Building, University of Sussex, Brighton BN1 9QH, UK

Obtaining accurate distributions of galaxy redshifts is a critical aspect of weak lensing cosmology experiments. One of the methods used to estimate and validate redshift distributions is to apply weights to a spectroscopic sample, so that their weighted photometry distribution matches the target sample. Herein, we estimate the selection bias in redshift that is introduced in this procedure. We do so by simulating the process of assembling a spectroscopic sample (including observer-assigned confidence flags) and highlight the impacts of spectroscopic target selection and redshift failures. We use the first year (Y1) weak lensing analysis in Dark Energy Survey (DES) as an example data set but the implications generalize to all similar weak lensing surveys. We find that using colour cuts that are not available to the weak lensing galaxies can introduce biases of up to Δz ~ 0.04 in the weighted mean redshift of different redshift intervals (Δz ~ 0.015 in the case most relevant to DES). To assess the impact of incompleteness in spectroscopic samples, we select only objects with high observer-defined confidence flags and compare the weighted mean redshift with the true mean. We find that the mean redshift of the DES Y1 weak lensing sample is typically biased at the Δz = 0.005–0.05 level after the weighting is applied. The bias we uncover can have either sign, depending on the samples and redshift interval considered. For the highest redshift bin, the bias is larger than the uncertainties in the other DES Y1 redshift calibration methods, justifying the decision of not using this method for the redshift estimations. We discuss several methods to mitigate this bias.

Research Organization:
SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Michigan, Ann Arbor, MI (United States)
Sponsoring Organization:
USDOE Office of Science (SC), High Energy Physics (HEP); National Science Foundation (NSF); USDOE
Contributing Organization:
DES Collaboration
Grant/Contract Number:
AC02-07CH11359; AST-138766; AST-1536171; AC05-00OR22725; SC0019193
OSTI ID:
1638777
Alternate ID(s):
OSTI ID: 1616311; OSTI ID: 1661213; OSTI ID: 1784539
Report Number(s):
arXiv:2003.10454; FERMILAB-PUB-20-106-AE; DES-2019-0498; oai:inspirehep.net:1787863; TRN: US2106439
Journal Information:
Monthly Notices of the Royal Astronomical Society, Vol. 496, Issue 4; ISSN 0035-8711
Publisher:
Royal Astronomical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

References (62)

OzDES multifibre spectroscopy for the Dark Energy Survey: 3-yr results and first data release journal July 2017
Calibrating Redshift Distributions beyond Spectroscopic Limits with Cross‐Correlations journal September 2008
CFHTLenS tomographic weak lensing: quantifying accurate redshift distributions journal March 2013
The Sdss-Iv Extended Baryon Oscillation Spectroscopic Survey: Overview and Early data journal February 2016
The VIMOS VLT deep survey: First epoch VVDS-deep survey: 11 564 spectra with 17.5  journal August 2005
Precision photometric redshift calibration for galaxy–galaxy weak lensing journal May 2008
Correcting cosmological parameter biases for all redshift surveys induced by estimating and reweighting redshift distributions journal December 2016
Self-organized formation of topologically correct feature maps journal January 1982
Marz: Manual and automatic redshifting software journal April 2016
The VIMOS Ultra-Deep Survey: ~10 000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2 < z ≃ 6 journal April 2015
Spectroscopic failures in photometric redshift calibration: cosmological biases and survey requirements journal August 2014
CFHTLenS and RCSLenS: testing photometric redshift distributions using angular cross-correlations with spectroscopic galaxy surveys journal September 2016
Hierarchical Modeling and Statistical Calibration for Photometric Redshifts journal August 2019
The dark Energy Camera journal October 2015
ZFOURGE: Using Composite Spectral Energy Distributions to Characterize Galaxy Populations at 1 < z < 4 journal August 2018
Redshift inference from the combination of galaxy colours and clustering in a hierarchical Bayesian model journal November 2018
The DEIMOS spectrograph for the Keck II Telescope: integration and testing conference March 2003
The cosmological simulation code gadget-2 journal December 2005
The VIMOS Public Extragalactic Redshift Survey (VIPERS): An unprecedented view of galaxies and large-scale structure at 0.5 < journal June 2014
The Deep2 Galaxy Redshift Survey: Design, Observations, data Reduction, and Redshifts journal August 2013
The Arizona CDFS Environment Survey (ACES): A Magellan/IMACS Spectroscopic Survey of the Chandra Deep Field-South: Arizona CDFS Environment Survey (ACES) journal August 2012
CFHTLenS tomographic weak lensing cosmological parameter constraints: Mitigating the impact of intrinsic galaxy alignments journal May 2013
Forward modeling of spectroscopic galaxy surveys: application to SDSS journal November 2018
Spectroscopic needs for imaging dark energy experiments journal March 2015
The first and second data releases of the Kilo-Degree Survey journal October 2015
Photometric redshift analysis in the Dark Energy Survey Science Verification data journal October 2014
The redshift distribution of cosmological samples: a forward modeling approach journal August 2017
zCOSMOS: A Large VLT/VIMOS Redshift Survey Covering 0 < z < 3 in the COSMOS Field journal September 2007
EZ: A Tool For Automatic Redshift Measurement journal July 2010
THE zCOSMOS 10k-BRIGHT SPECTROSCOPIC SAMPLE journal September 2009
Improved photometric redshifts via enhanced estimates of system response, galaxy templates and magnitude priors journal March 2013
The VIMOS Public Extragalactic Redshift Survey (VIPERS): Science Highlights and Final Data Release text January 2017
Estimating the redshift distribution of photometric galaxy samples journal October 2008
The Complete Calibration of the Color–Redshift Relation (C3R2) Survey: Survey Overview and Data Release 1 journal May 2017
The Prism Multi-Object Survey (Primus). ii. data Reduction and Redshift Fitting journal April 2013
Accurate photometric redshift probability density estimation – method comparison and application journal August 2015
CFHTLenS: improving the quality of photometric redshifts with precision photometry★: CFHTLenS: photometric redshifts journal February 2012
Bayesian Photometric Redshift Estimation journal June 2000
The WIRCam Deep Survey: I. Counts, colours, and mass-functions derived from near-infrared imaging in the CFHTLS deep fields⋆ journal August 2012
The FORS Deep Field: Photometric Data and Photometric Redshifts book January 2003
The VIMOS Ultra Deep Survey first data release: Spectra and spectroscopic redshifts of 698 objects up to z spec ~ 6 in CANDELS journal April 2017
CFHTLenS revisited: assessing concordance with Planck including astrophysical systematics journal October 2016
Transients from initial conditions in cosmological simulations journal November 2006
DES science portal: Computing photometric redshifts journal October 2018
3D-HST: A WIDE-FIELD GRISM SPECTROSCOPIC SURVEY WITH THE HUBBLE SPACE TELESCOPE journal May 2012
Commissioning and performances of the VLT-VIMOS conference March 2003
The Vimos VLT deep survey: Global properties of 20 000 galaxies in the journal June 2008
The identification of post-starburst galaxies at z ∼ 1 using multiwavelength photometry: a spectroscopic verification journal April 2016
The Cosmic Evolution Survey (COSMOS): Overview journal September 2007
Sample variance in photometric redshift calibration: cosmological biases and survey requirements: Sample variance in photo-z calibration journal April 2012
Studying the emergence of the red sequence through galaxy clustering: host halo masses at z > 2 journal April 2013
Phenotypic redshifts with self-organizing maps: A novel method to characterize redshift distributions of source galaxies for weak lensing journal August 2019
Photometric redshifts for Hyper Suprime-Cam Subaru Strategic Program Data Release 1 journal October 2017
Estimating redshift distributions using hierarchical logistic Gaussian processes journal November 2019
THE EVOLUTION OF METALLICITY AND METALLICITY GRADIENTS FROM z = 2.7 TO 0.6 WITH KMOS 3D journal August 2016
DNF – Galaxy photometric redshift by Directional Neighbourhood Fitting journal April 2016
Dark Energy Survey Year 1 Results: redshift distributions of the weak-lensing source galaxies journal April 2018
Mapping the Galaxy Color–Redshift Relation: Optimal Photometric Redshift Calibration Strategies for Cosmology Surveys journal October 2015
THE FMOS-COSMOS SURVEY OF STAR-FORMING GALAXIES AT z ∼ 1.6. IV. EXCITATION STATE AND CHEMICAL ENRICHMENT OF THE INTERSTELLAR MEDIUM journal January 2017
The Complete Calibration of the Color–Redshift Relation (C3R2) Survey: Analysis and Data Release 2 journal May 2019
The VIMOS Public Extragalactic Survey (VIPERS): First Data Release of 57 204 spectroscopic measurements journal January 2014
Selection biases in empirical p(z) methods for weak lensing journal February 2017