Self-calibrating the gravitational shear-intrinsic ellipticity-intrinsic ellipticity (GII) cross-correlation

Abstract

We extend the 3-point intrinsic alignment self-calibration technique to the gravitational shear-intrinsic ellipticity-intrinsic ellipticity (GII) bispectrum. The proposed technique will allow the measurement and removal of the GII intrinsic alignment contamination from the cross-correlation weak lensing signal. While significantly decreased from using cross-correlations instead of auto-correlation in a single photo-z bin, the GII contamination persists in adjacent photo-z bins and must be accounted for and removed from the lensing signal. We relate the GII and galaxy density-intrinsic ellipticity-intrinsic ellipticity (gII) bispectra through use of the galaxy bias, and develop the estimator necessary to isolate the gII bispectrum from observations. We find that the GII self-calibration technique performs at a level comparable to that of the gravitational shear-gravitational shear-intrinsic ellipticity correlation (GGI) self-calibration technique, with measurement error introduced through the gII estimator generally negligible when compared to minimum survey error. The accuracy of the relationship between the GII and gII bispectra typically allows the GII self-calibration to reduce the GII contamination by a factor of 10 or more for all adjacent photo-z bin combinations at $\ell >300$. For larger scales, we find that the GII contamination can be reduced by a factor of 3-5 or more. The GII self-calibration technique is complementary to the existing GGI self-calibration technique, which together will allow the total intrinsic alignment cross-correlation signal in 3-point weak lensing to be measured and removed.

18 pages, 4 figures. Several sections have been reworded, results and conclusions are all the same. arXiv admin note: substantial text overlap with arXiv:1109.4896

References in corpus (16)

• Dark energy constraints from cosmic shear power spectra: impact of intrinsic alignments on photometric redshift requirements
• Intrinsic galaxy alignments from the 2SLAQ and SDSS surveys: luminosity and redshift scalings and implications for weak lensing surveys
• Constraints on intrinsic alignment contamination of weak lensing surveys using the MegaZ-LRG sample
• Potential sources of contamination to weak lensing measurements: constraints from N-body simulations
• Primordial non-Gaussianity, scale-dependent bias, and the bispectrum of galaxies
• Testing the tidal alignment model of galaxy intrinsic alignment
• The removal of shear-ellipticity correlations from the cosmic shear signal via nulling techniques
• The Gravitational Shear--Intrinsic Ellipticity Correlation Functions of Luminous Red Galaxies in Observation and in the $\Lambda$CDM Model
• Alignment between galaxies and large-scale structure
• From Weak Lensing to non-Gaussianity via Minkowski Functionals
• Sources of contamination to weak lensing three-point statistics: constraints from N-body simulations
• Self-Calibration for 3-point Intrinsic Alignment Auto-Correlations in Weak Lensing Surveys
• Self-Calibration Technique for 3-point Intrinsic Alignment Correlations in Weak Lensing Surveys
• Controlling intrinsic-shear alignment in three-point weak lensing statistics
• Testing the Gaussianity and Statistical Isotropy of the Universe
• Intrinsic alignment boosting: Direct measurement of intrinsic alignments in cosmic shear data

Cited by in corpus (13)

• Testing General Relativity in Cosmology
• The Intrinsic Alignment of Galaxies and its Impact on Weak Gravitational Lensing in an Era of Precision Cosmology
• Cross-correlation between cosmic microwave background lensing and galaxy intrinsic alignment as a contaminant to gravitational lensing cross-correlated probes of the universe
• Angular ellipticity correlations in a composite alignment model for elliptical and spiral galaxies and inference from weak lensing
• Effects of Self-Calibration of Intrinsic Alignment on Cosmological Parameter Constraints from Future Cosmic Shear Surveys
• KiDS-1000: cross-correlation with Planck cosmic microwave background lensing and intrinsic alignment removal with self-calibration
• Weak lensing power spectrum reconstruction by counting galaxies.-- I: the ABS method
• Self-calibration method for II and GI types of intrinsic alignments of galaxies
• Separating the Intrinsic Alignment Signal and the Lensing Signal using Self-Calibration in Photo-z Surveys with KiDS450 and KV450 Data
• The source-lens clustering effect in the context of lensing tomography and its self-calibration
• Verifications of scaling relations useful for the intrinsic alignment self-calibration
• A rising tide: Intrinsic alignments since the turn of the millennium
• A direct detection method of galaxy intrinsic ellipticity-gravitational shear correlation in non-linear regimes using self-calibration