def METHOD_NAME(self, energy, scale):
    """Evaluate dark matter annihilation model."""
    flux = (
        scale
        * self.jfactor
        * self.THERMAL_RELIC_CROSS_SECTION
        * self.primary_flux(energy=energy * (1 + self.z))
        / self.k
        / self.mass
        / self.mass
        / (4 * np.pi)
    )
    return flux