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This content will become publicly available on March 28, 2017

Title: Galaxy clustering with photometric surveys using PDF redshift information

Here, photometric surveys produce large-area maps of the galaxy distribution, but with less accurate redshift information than is obtained from spectroscopic methods. Modern photometric redshift (photo-z) algorithms use galaxy magnitudes, or colors, that are obtained through multi-band imaging to produce a probability density function (PDF) for each galaxy in the map. We used simulated data to study the effect of using different photo-z estimators to assign galaxies to redshift bins in order to compare their effects on angular clustering and galaxy bias measurements. We found that if we use the entire PDF, rather than a single-point (mean or mode) estimate, the deviations are less biased, especially when using narrow redshift bins. When the redshift bin widths are $$\Delta z=0.1$$, the use of the entire PDF reduces the typical measurement bias from 5%, when using single point estimates, to 3%.
 [1] ;  [2] ;  [3] ;  [2] ;  [1]
  1. Univ. of Illinois, Urbana, IL (United States)
  2. Univ. of Illinois, Urbana, IL (United States); National Center for Supercomputing Applications, Urbana, IL (United States)
  3. Univ. of Illinois, Urbana, IL (United States); Centro de Investigaciones Energeticas, Medioambientales y Technologicas (CIEMAT), Madrid (Spain)
Publication Date:
OSTI Identifier:
Report Number(s):
arXiv:1601.00357; FERMILAB-PUB--16-183-AE
Journal ID: ISSN 0035-8711; 1412017
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Volume: 459; Journal Issue: 2; Journal ID: ISSN 0035-8711
Royal Astronomical Society
Research Org:
Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS methods: statistical; galaxies: distances and redshifts; cosmology: large-scale structure of Universe