Tidal alignment of galaxies

  title={Tidal alignment of galaxies},
  author={Jonathan A. Blazek and Zvonimir Vlah and Uros Seljak},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={015 - 015}
We develop an analytic model for galaxy intrinsic alignments (IA) based on the theory of tidal alignment. We calculate all relevant nonlinear corrections at one-loop order, including effects from nonlinear density evolution, galaxy biasing, and source density weighting. Contributions from density weighting are found to be particularly important and lead to bias dependence of the IA amplitude, even on large scales. This effect may be responsible for much of the luminosity dependence in IA… 

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