CFHTLenS tomographic weak lensing: Quantifying accurate redshift distributions
The Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) comprises deep multi-colour (u*g'r'i'z') photometry spanning 154 square degrees, with accurate photometric redshifts and shape measurements. We demonstrate that the redshift probability distribution function summed over...
Main Authors: | , , , , , , , , , , , , , , , , , , , , |
---|---|
Format: | Journal article |
Language: | English |
Published: |
2012
|
_version_ | 1826271731375931392 |
---|---|
author | Benjamin, J Waerbeke, L Heymans, C Kilbinger, M Erben, T Hildebrandt, H Hoekstra, H Kitching, T Mellier, Y Miller, L Rowe, B Schrabback, T Simpson, F Coupon, J Fu, L Harnois-Déraps, J Hudson, M Kuijken, K Semboloni, E Vafaei, S Velander, M |
author_facet | Benjamin, J Waerbeke, L Heymans, C Kilbinger, M Erben, T Hildebrandt, H Hoekstra, H Kitching, T Mellier, Y Miller, L Rowe, B Schrabback, T Simpson, F Coupon, J Fu, L Harnois-Déraps, J Hudson, M Kuijken, K Semboloni, E Vafaei, S Velander, M |
author_sort | Benjamin, J |
collection | OXFORD |
description | The Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) comprises deep multi-colour (u*g'r'i'z') photometry spanning 154 square degrees, with accurate photometric redshifts and shape measurements. We demonstrate that the redshift probability distribution function summed over galaxies provides an accurate representation of the galaxy redshift distribution accounting for random and catastrophic errors for galaxies with best fitting photometric redshifts z_p < 1.3. We present cosmological constraints using tomographic weak gravitational lensing by large-scale structure. We use two broad redshift bins 0.5 < z_p <= 0.85 and 0.85 < z_p <= 1.3 free of intrinsic alignment contamination, and measure the shear correlation function on angular scales in the range ~1-40 arcmin. We show that the problematic redshift scaling of the shear signal, found in previous CFHTLS data analyses, does not afflict the CFHTLenS data. For a flat Lambda-CDM model and a fixed matter density Omega_m=0.27, we find the normalisation of the matter power spectrum sigma_8=0.771 \pm 0.041. When combined with cosmic microwave background data (WMAP7), baryon acoustic oscillation data (BOSS), and a prior on the Hubble constant from the HST distance ladder, we find that CFHTLenS improves the precision of the fully marginalised parameter estimates by an average factor of 1.5-2. Combining our results with the above cosmological probes, we find Omega_m=0.2762 \pm 0.0074 and sigma_8=0.802 \pm 0.013. |
first_indexed | 2024-03-06T22:01:20Z |
format | Journal article |
id | oxford-uuid:4eae6b3e-2aa5-492d-bfc7-b3fd81f151ad |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-06T22:01:20Z |
publishDate | 2012 |
record_format | dspace |
spelling | oxford-uuid:4eae6b3e-2aa5-492d-bfc7-b3fd81f151ad2022-03-26T16:02:39ZCFHTLenS tomographic weak lensing: Quantifying accurate redshift distributionsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:4eae6b3e-2aa5-492d-bfc7-b3fd81f151adEnglishSymplectic Elements at Oxford2012Benjamin, JWaerbeke, LHeymans, CKilbinger, MErben, THildebrandt, HHoekstra, HKitching, TMellier, YMiller, LRowe, BSchrabback, TSimpson, FCoupon, JFu, LHarnois-Déraps, JHudson, MKuijken, KSemboloni, EVafaei, SVelander, MThe Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) comprises deep multi-colour (u*g'r'i'z') photometry spanning 154 square degrees, with accurate photometric redshifts and shape measurements. We demonstrate that the redshift probability distribution function summed over galaxies provides an accurate representation of the galaxy redshift distribution accounting for random and catastrophic errors for galaxies with best fitting photometric redshifts z_p < 1.3. We present cosmological constraints using tomographic weak gravitational lensing by large-scale structure. We use two broad redshift bins 0.5 < z_p <= 0.85 and 0.85 < z_p <= 1.3 free of intrinsic alignment contamination, and measure the shear correlation function on angular scales in the range ~1-40 arcmin. We show that the problematic redshift scaling of the shear signal, found in previous CFHTLS data analyses, does not afflict the CFHTLenS data. For a flat Lambda-CDM model and a fixed matter density Omega_m=0.27, we find the normalisation of the matter power spectrum sigma_8=0.771 \pm 0.041. When combined with cosmic microwave background data (WMAP7), baryon acoustic oscillation data (BOSS), and a prior on the Hubble constant from the HST distance ladder, we find that CFHTLenS improves the precision of the fully marginalised parameter estimates by an average factor of 1.5-2. Combining our results with the above cosmological probes, we find Omega_m=0.2762 \pm 0.0074 and sigma_8=0.802 \pm 0.013. |
spellingShingle | Benjamin, J Waerbeke, L Heymans, C Kilbinger, M Erben, T Hildebrandt, H Hoekstra, H Kitching, T Mellier, Y Miller, L Rowe, B Schrabback, T Simpson, F Coupon, J Fu, L Harnois-Déraps, J Hudson, M Kuijken, K Semboloni, E Vafaei, S Velander, M CFHTLenS tomographic weak lensing: Quantifying accurate redshift distributions |
title | CFHTLenS tomographic weak lensing: Quantifying accurate redshift
distributions |
title_full | CFHTLenS tomographic weak lensing: Quantifying accurate redshift
distributions |
title_fullStr | CFHTLenS tomographic weak lensing: Quantifying accurate redshift
distributions |
title_full_unstemmed | CFHTLenS tomographic weak lensing: Quantifying accurate redshift
distributions |
title_short | CFHTLenS tomographic weak lensing: Quantifying accurate redshift
distributions |
title_sort | cfhtlens tomographic weak lensing quantifying accurate redshift distributions |
work_keys_str_mv | AT benjaminj cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT waerbekel cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT heymansc cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT kilbingerm cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT erbent cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT hildebrandth cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT hoekstrah cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT kitchingt cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT melliery cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT millerl cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT roweb cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT schrabbackt cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT simpsonf cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT couponj cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT ful cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT harnoisderapsj cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT hudsonm cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT kuijkenk cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT sembolonie cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT vafaeis cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions AT velanderm cfhtlenstomographicweaklensingquantifyingaccurateredshiftdistributions |