add_colours
================================================

Combine red and blue galaxy intrinsic alignment signals based on color fractions

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| File        | intrinsic_alignments/add_colours/add_colours.py |
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| Attribution | Simon Samuroff                                  |
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| URL         |                                                 |
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This module combines intrinsic alignment signals from red and blue galaxy
populations to compute the total IA signal for a galaxy sample with mixed
colors. It assumes that separate IA power spectra have been computed for
red and blue galaxies.

The module uses color fractions and separate amplitude/evolution parameters
for red and blue populations to linearly combine the II and GI power spectra.
Cross-terms between red and blue populations are included assuming they
follow the geometric mean of the individual population spectra.


Assumptions
-----------

 - Separate IA signals computed for red and blue galaxy populations
 - Galaxy sample has known red/blue fractions and amplitude/evolution parameters



Setup Parameters
----------------

.. list-table::
   :header-rows: 1

   * - Name
     - Type
     - Default
     - Description

   * - catalogue
     - str
     - 
     - Section name containing galaxy color fraction information


Input values
----------------

.. list-table::
   :header-rows: 1

   * - Section
     - Name
     - Type
     - Default
     - Description

   * - catalogue_section
     - red_fraction
     - real
     - 
     - Fraction of red galaxies in the sample
   * - intrinsic_alignment_parameters
     - A_red
     - real
     - 
     - IA amplitude for red galaxies
   * - 
     - A_blue
     - real
     - 
     - IA amplitude for blue galaxies
   * - 
     - alpha_red
     - real
     - 
     - Redshift evolution parameter for red galaxies
   * - 
     - alpha_blue
     - real
     - 
     - Redshift evolution parameter for blue galaxies
   * - 
     - z
     - real 1d
     - 
     - Redshift values for IA power spectra
   * - 
     - k_h
     - real 1d
     - 
     - Wavenumber values in h/Mpc
   * - 
     - P_II_red
     - real 2d
     - 
     - Intrinsic-intrinsic power spectrum for red galaxies
   * - 
     - P_II_blue
     - real 2d
     - 
     - Intrinsic-intrinsic power spectrum for blue galaxies
   * - 
     - P_GI_red
     - real 2d
     - 
     - Galaxy-intrinsic cross power spectrum for red galaxies
   * - 
     - P_GI_blue
     - real 2d
     - 
     - Galaxy-intrinsic cross power spectrum for blue galaxies


Output values
----------------


.. list-table:: Output values
   :header-rows: 1

   * - Section
     - Name
     - Type
     - Description

   * - intrinsic_alignment_parameters
     - z
     - real 1d
     - Redshift values for combined IA power spectra
   * - 
     - k_h
     - real 1d
     - Wavenumber values in h/Mpc
   * - 
     - P_II
     - real 2d
     - Combined intrinsic-intrinsic power spectrum
   * - 
     - P_GI
     - real 2d
     - Combined galaxy-intrinsic cross power spectrum