Macroscopic transport cross section from macroscopic scattering cross section
=============================================================================

Macroscopic transport cross section can be found using the macroscopic scattering cross
section and the averaged cosine of the scattering angle.

**Links:**

#. `NuclearPower <https://www.nuclear-power.com/nuclear-power/reactor-physics/neutron-diffusion-theory/diffusion-coefficient/>`__.
#. `ScienceDirect, neutron transport <https://www.sciencedirect.com/topics/engineering/neutron-transport>`__.

.. py:currentmodule:: symplyphysics.laws.nuclear.macroscopic_transport_cross_section

.. py:data:: macroscopic_scattering_cross_section

    :attr:`~symplyphysics.symbols.nuclear.macroscopic_cross_section` of scattering.

Symbol:
    :code:`Sigma_s`

Latex:
    :math:`\sigma_\text{s}`

Dimension:
    :code:`1/length`


.. py:data:: average_scattering_angle_cosine

    Average of the cosine of the angle at which neutrons are scattered in the medium in the
    lab system.

Symbol:
    :code:`mu`

Latex:
    :math:`\mu`

Dimension:
    :code:`dimensionless`


.. py:data:: macroscopic_transport_cross_section

    :attr:`~symplyphysics.symbols.nuclear.macroscopic_cross_section` of neutron transport (i.e. the movement of neutrons
    through the material).

Symbol:
    :code:`Sigma_tr`

Latex:
    :math:`\Sigma_\text{tr}`

Dimension:
    :code:`1/length`


.. py:data:: law

    :code:`Sigma_tr = Sigma_s * (1 - mu)`


    Latex:
        .. math::
            \Sigma_\text{tr} = \sigma_\text{s} \left(1 - \mu\right)