Average cosine of scattering angle from mass number
===================================================

Averaged cosine of the angle of neutron scattering depends on the mass number of the
target nucleus.

**Links:**

#. `NuclearPower <https://www.nuclear-power.com/nuclear-power/reactor-physics/neutron-diffusion-theory/diffusion-coefficient/>`__.

.. py:currentmodule:: symplyphysics.laws.nuclear.most_neutron_energies_scattering_angle_average_cosine

.. py:data:: mass_number

    :attr:`~symplyphysics.symbols.chemistry.mass_number` of the target nucleus.

Symbol:
    :code:`A`

Latex:
    :math:`A`

Dimension:
    :code:`dimensionless`


.. 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:: law

    :code:`mu = 2 / (3 * A)`


    Latex:
        .. math::
            \mu = \frac{2}{3 A}