2015
DOI: 10.1093/mnras/stv1655
|View full text |Cite
|
Sign up to set email alerts
|

Contamination of early-type galaxy alignments to galaxy lensing–CMB lensing cross-correlation

Abstract: Galaxy shapes are subject to distortions due to the tidal field of the Universe. The cross-correlation of galaxy lensing with the lensing of the Cosmic Microwave Background (CMB) cannot easily be separated from the cross-correlation of galaxy intrinsic shapes with CMB lensing. Previous work suggested that the intrinsic alignment contamination can be 15% of this cross-spectrum for the CFHT Stripe 82 (CS82) and Atacama Cosmology Telescope surveys. Here we re-examine these estimates using upto-date observational … Show more

Help me understand this report
View preprint versions

Search citation statements

Order By: Relevance

Paper Sections

Select...
3
1
1

Citation Types

3
29
0

Year Published

2015
2015
2023
2023

Publication Types

Select...
7

Relationship

3
4

Authors

Journals

citations
Cited by 30 publications
(32 citation statements)
references
References 55 publications
3
29
0
Order By: Relevance
“…Indeed, at low redshift, IA contaminate the power spectrum by up to 5%-10% for κ gal κ gal and κ gal κ CMB , in agreement with [25][26][27][28]102,103]. However, this bias becomes much smaller at higher redshift (the IA signal is roughly constant with redshift, while the lensing signal increases), and the higher redshift power spectra are measured with the best signal-to-noise ratio.…”
Section: B Approaching or Surpassing The Lsst Requirements With Cmb S4supporting
confidence: 65%
See 2 more Smart Citations
“…Indeed, at low redshift, IA contaminate the power spectrum by up to 5%-10% for κ gal κ gal and κ gal κ CMB , in agreement with [25][26][27][28]102,103]. However, this bias becomes much smaller at higher redshift (the IA signal is roughly constant with redshift, while the lensing signal increases), and the higher redshift power spectra are measured with the best signal-to-noise ratio.…”
Section: B Approaching or Surpassing The Lsst Requirements With Cmb S4supporting
confidence: 65%
“…II D, our model for the IA contamination extrapolates the observed IA strength of early-type galaxies to high redshifts but does not include the alignment of late-type galaxies, which has not been detected so far. Chisari et al [103] find that latetype galaxy alignments, assuming an alignment strength consistent with the upper detection limits, may double the IA contamination to nontomographic κ gal κ CMB correlations. It will be important to revisit this calculation as better models and observations of late-type galaxy alignments become available.…”
Section: B Approaching or Surpassing The Lsst Requirements With Cmb S4mentioning
confidence: 92%
See 1 more Smart Citation
“…In addition to potentially biasing cosmological parameters and bias measurements, it could also impact efforts to use cross correlations to tighten constraints on nuisance parameters describing instrumental systematics and contaminating signals. In the specific case of galaxy lensing measurements, the use of cross-correlations is emerging as standard practice to improve determination of nuisance parameters and minimize the impact of systematics [30,90,91]. As a concrete example, we consider the case of intrinsic alignments (IA): in addition to the correlation with observed galaxy shapes due to gravitational lensing, the galaxy shapes can also be intrinsically aligned with the same local tidal field that contributes to the CMB lensing signal [92].…”
Section: Detectability For Future Surveysmentioning
confidence: 99%
“…(5) on those from [40]. However, where they assume that all galaxies contribute equally to the intrinsic alignment signal, we follow [41] and assume that only red galaxies contribute. We additionally make the simplifying assumption that the fraction of red galaxies f red is constant over the redshifts that we consider.…”
Section: A Observational Probesmentioning
confidence: 99%