Radio-Optical Galaxy Shape Correlations in the COSMOS Field

Abstract

We investigate the correlations in galaxy shapes between optical and radio wavelengths using archival observations of the COSMOS field. Cross-correlation studies between different wavebands will become increasingly important for precision cosmology as future large surveys may be dominated by systematic rather than statistical errors. In the case of weak lensing, galaxy shapes must be measured to extraordinary accuracy (shear systematics of $<0.01\%$) in order to achieve good constraints on dark energy parameters. By using shape information from overlapping surveys in optical and radio bands, robustness to systematics may be significantly improved without loss of constraining power. Here we use HST-ACS optical data, VLA radio data, and extensive simulations to investigate both our ability to make precision measurements of source shapes from realistic radio data, and to constrain the intrinsic astrophysical scatter between the shapes of galaxies as measured in the optical and radio wavebands. By producing a new image from the VLA-COSMOS L-band radio visibility data that is well suited to galaxy shape measurements, we are able to extract precise measurements of galaxy position angles. Comparing to corresponding measurements from the HST optical image, we set a lower limit on the intrinsic astrophysical scatter in position angles, between the optical and radio bands, of ${\sigma }_{\alpha }>0.212\pi$ radians (or $38.2^{\circ }$) at a $95\%$ confidence level.

arXiv comment17 pages, 13 figure, 5 tables. Updated to match published version with a number of typographical corrections

References in corpus (32)

• The COSMOS Survey: Hubble Space Telescope / Advanced Camera for Surveys (HST/ACS) Observations and Data Processing
• Cosmology with cosmic shear observations: a review
• The non-coplanar baselines effect in radio interferometry: The W-Projection algorithm
• The VLA-COSMOS Survey: II. Source Catalog of the Large Project
• The COSMOS-WIRCam near-infrared imaging survey: I: BzK selected passive and star forming galaxy candidates at z>1.4
• The Blanco Cosmology Survey: Data Acquisition, Processing, Calibration, Quality Diagnostics and Data Release
• The DES Science Verification Weak Lensing Shear Catalogues
• Systematic Bias in Cosmic Shear: Beyond the Fisher Matrix
• Cosmology from Cosmic Shear with DES Science Verification Data
• Image Analysis for Cosmology: Results from the GREAT10 Galaxy Challenge
• Noise bias in weak lensing shape measurements
• Results of the GREAT08 Challenge: An image analysis competition for cosmological lensing
• IM3SHAPE: A maximum-likelihood galaxy shear measurement code for cosmic gravitational lensing
• Measurement and Calibration of Noise Bias in Weak Lensing Galaxy Shape Estimation
• Cosmic Shear Results from the Deep Lens Survey - II: Full Cosmological Parameter Constraints from Tomography
• The effects of seeing on Sersic profiles
• SKA Weak Lensing I: Cosmological Forecasts and the Power of Radio-Optical Cross-Correlations
• Weak Lensing by Large-Scale Structure with the FIRST Radio Survey
• A generalised Measurement Equation and van Cittert-Zernike theorem for wide-field radio astronomical interferometry
• Image Analysis for Cosmology: Results from the GREAT10 Star Challenge
• SKA Weak Lensing II: Simulated Performance and Survey Design Considerations
• Radio and optical orientations of galaxies
• A direct measurement of tomographic lensing power spectra from CFHTLenS
• SKA Weak Lensing III: Added Value of Multi-Wavelength Synergies for the Mitigation of Systematics
• Polarization as an indicator of intrinsic alignment in radio weak lensing
• A Technique for Weak Lensing with Velocity Maps: Eliminating Ellipticity Noise in HI Radio Observations
• Cross-correlation cosmic shear with the SDSS and VLA FIRST surveys
• Radio Weak Gravitational Lensing with VLA and MERLIN
• Shape Reconstruction and Weak Lensing Measurement with Interferometers: A Shapelet Approach
• Separating weak lensing and intrinsic alignments using radio observations
• Weak lensing using only galaxy position angles
• A demonstration of position angle-only weak lensing shear estimators on the GREAT3 simulations

Cited by in corpus (13)

• Cosmology with Phase 1 of the Square Kilometre Array; Red Book 2018: Technical specifications and performance forecasts
• The Tiered Radio Extragalactic Continuum Simulation (T-RECS)
• Deep Radio Interferometric Imaging with POLISH: DSA-2000 and weak lensing
• SuperCLASS -- III. Weak lensing from radio and optical observations in Data Release 1
• Radio Weak Lensing Shear Measurement in the Visibility Domain - II. Source Extraction
• Radio Galaxy Shape Measurement with Hamiltonian Monte Carlo in the Visibility Domain
• The morphology of star-forming gas and its alignment with galaxies and dark matter haloes in the EAGLE simulations
• Galaxy-galaxy and galaxy-cluster lensing with the SDSS and FIRST surveys
• SuperCLASS -- I. The Super CLuster Assisted Shear Survey: Project overview and Data Release 1
• Radio-Optical Galaxy Shape and Shear Correlations in the COSMOS Field using 3 GHz VLA Observations
• Intrinsic alignments of the extended radio continuum emission of galaxies in the EAGLE simulations
• Prospects for radio weak lensing: studies using LOFAR observations in the ELAIS-N1 field
• An empirical model of the extragalactic radio background