Set the pitch-angle distribution to a Gaussian loss cone.

        **Call signature**

        *boundary_rad*
          The angle inside which there are no losses, in radians.
        *expwidth*
          The characteristic width of the Gaussian loss profile
          *in direction-cosine units*.
        Returns
          *self* for convenience in chaining.

        See ``OnlineI.pdf`` in the Supplementary Data for a precise
        definition. (And note the distinction between α_c and μ_c since not
        everything is direction cosines.)

def set_padist_gaussian_loss_cone(self, boundary_rad, expwidth):
        """Set the pitch-angle distribution to a Gaussian loss cone.

        **Call signature**

        *boundary_rad*
          The angle inside which there are no losses, in radians.
        *expwidth*
          The characteristic width of the Gaussian loss profile
          *in direction-cosine units*.
        Returns
          *self* for convenience in chaining.

        See ``OnlineI.pdf`` in the Supplementary Data for a precise
        definition. (And note the distinction between α_c and μ_c since not
        everything is direction cosines.)

        """
        self.in_vals[IN_VAL_PADIST] = PADIST_GLC
        self.in_vals[IN_VAL_LCBDY] = boundary_rad * 180 / np.pi # rad => deg
        self.in_vals[IN_VAL_DELTAMU] = expwidth
        return self