mulenssystem.py 文件源码

def theta_E(self):
        """
        *astropy.Quantity*, read-only

        The angular Einstein Radius in milliarcseconds.
        """
        kappa = (4. * G / (c**2 * au)).to(
            u.mas/u.Msun, equivalencies=u.dimensionless_angles())

        return np.sqrt(
            kappa * self.lens.total_mass.to(u.solMass) *
            self.pi_rel.to(u.mas))