1. Galaxy shape statistics in the effective field theory
- Author
-
Vlah, Zvonimir, Chisari, Nora Elisa, Schmidt, Fabian, Sub String Theory Cosmology and ElemPart, Theoretical Physics, Vlah, Zvonimir [0000-0002-9274-5768], Apollo - University of Cambridge Repository, Sub String Theory Cosmology and ElemPart, and Theoretical Physics
- Subjects
Astrophysics and Astronomy ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,media_common.quotation_subject ,gravitational lensing ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,power spectrum ,weak gravitational lensing ,01 natural sciences ,0103 physical sciences ,Statistics ,Effective field theory ,galaxy surveys ,Weak gravitational lensing ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,010308 nuclear & particles physics ,paper ,Spectral density ,Astronomy and Astrophysics ,Redshift ,Galaxy ,Gravitational lens ,Distribution (mathematics) ,Sky ,astro-ph.CO ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Intrinsic galaxy alignments yield an important contribution to the observed statistics of galaxy shapes. The general bias expansion for galaxy sizes and shapes in three dimensions has been recently described by Vlah, Chisari \& Schmidt using the general perturbative effective field theory (EFT) framework, in analogy to the clustering of galaxies. In this work, we present a formalism that uses the properties of spherical tensors to project galaxy shapes onto the observed sky in the flat-sky approximation and compute the two-point functions at next-to-leading order as well as the leading-order three-point functions of galaxy shapes and number counts. The resulting expressions are given in forms that are convenient for efficient numerical implementation. For a source redshift distribution typical of Stage IV surveys, we find that that nonlinear intrinsic alignment contributions to galaxy shape correlations become relevant at angular wavenumbers $l \gtrsim 100$., 32 pages, 5 figures
- Published
- 2020