Power spectrum of intrinsic alignments of galaxies in IllustrisTNG

  title={Power spectrum of intrinsic alignments of galaxies in IllustrisTNG},
  author={Jingjing Shi and Toshiki Kurita and Masahiro Takada and Ken Osato and Yosuke Kobayashi and Takahiro Nishimichi},
  journal={Journal of Cosmology and Astroparticle Physics},
We present the 3-dimensional intrinsic alignment power spectra between the projected 2d galaxy shape/spin and the 3d tidal field across 0.1<k/<60 using cosmological hydrodynamical simulation, Illustris-TNG300, at redshifts ranging from 0.3 to 2. The shape-tidal field alignment increases with galaxy mass and the linear alignment coefficient AIA, defined with respect to the primordial tidal field, is found to have weak redshift dependence. We also show a promising detection of the shape/spin… 
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