3D Photometric Cosmic Shear
Here we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift probability distributions for individual galaxies can be directly...
| Main Authors: | , , |
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| Format: | Journal article |
| Published: |
2010
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| _version_ | 1797104183119183872 |
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| author | Kitching, T Heavens, A Miller, L |
| author_facet | Kitching, T Heavens, A Miller, L |
| author_sort | Kitching, T |
| collection | OXFORD |
| description | Here we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift probability distributions for individual galaxies can be directly included in this statistic with no averaging. We also include the Limber approximation, considerably simplifying full 3D cosmic shear analysis, and we investigate its range of applicability. Finally we show the relationship between weak lensing tomography and the 3D cosmic shear field itself; the steps connecting them being the Limber approximation, a harmonic-space transform and a discretisation in wavenumber. Each method has its advantages: 3D cosmic shear analysis allows straightforward inclusion of all relevant modes, thus ensuring minimum error bars, and direct control of the range of physical wavenumbers probed, to avoid the uncertain highly nonlinear regime. On the other hand, tomography is more convenient for checking systematics through direct investigation of the redshift dependence of the signal. Finally, for tomography, we suggest that the angular modes probed should be redshift-dependent, to recover some of the 3D advantages. |
| first_indexed | 2024-03-07T06:30:16Z |
| format | Journal article |
| id | oxford-uuid:f5c11429-7cae-4c9a-a215-0bcaf4067462 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T06:30:16Z |
| publishDate | 2010 |
| record_format | dspace |
| spelling | oxford-uuid:f5c11429-7cae-4c9a-a215-0bcaf40674622022-03-27T12:29:38Z3D Photometric Cosmic ShearJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:f5c11429-7cae-4c9a-a215-0bcaf4067462Symplectic Elements at Oxford2010Kitching, THeavens, AMiller, LHere we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift probability distributions for individual galaxies can be directly included in this statistic with no averaging. We also include the Limber approximation, considerably simplifying full 3D cosmic shear analysis, and we investigate its range of applicability. Finally we show the relationship between weak lensing tomography and the 3D cosmic shear field itself; the steps connecting them being the Limber approximation, a harmonic-space transform and a discretisation in wavenumber. Each method has its advantages: 3D cosmic shear analysis allows straightforward inclusion of all relevant modes, thus ensuring minimum error bars, and direct control of the range of physical wavenumbers probed, to avoid the uncertain highly nonlinear regime. On the other hand, tomography is more convenient for checking systematics through direct investigation of the redshift dependence of the signal. Finally, for tomography, we suggest that the angular modes probed should be redshift-dependent, to recover some of the 3D advantages. |
| spellingShingle | Kitching, T Heavens, A Miller, L 3D Photometric Cosmic Shear |
| title | 3D Photometric Cosmic Shear |
| title_full | 3D Photometric Cosmic Shear |
| title_fullStr | 3D Photometric Cosmic Shear |
| title_full_unstemmed | 3D Photometric Cosmic Shear |
| title_short | 3D Photometric Cosmic Shear |
| title_sort | 3d photometric cosmic shear |
| work_keys_str_mv | AT kitchingt 3dphotometriccosmicshear AT heavensa 3dphotometriccosmicshear AT millerl 3dphotometriccosmicshear |