Boundary_layer.power_law_index
==============================
The exponent :math:`\alpha` in a power law SED applied to an AGN-style power law source for a non-AGN system.
central source of the form :math:`L_\nu=K\nu^\alpha`.

Type
  Double

Values
  Any - must use negative (-) sign for negative indexes.

File
  `setup_star_bh.c <https://github.com/sirocco-rt/sirocco/blob/master/source/setup_star_bh.c>`_


Parent(s)
  * :ref:`Boundary_layer.rad_type_to_make_wind`: ``power_law``