@property<EOL><INDENT>def r200(self):<DEDENT>
if self._r200 is None:<EOL><INDENT>raise AttributeError('<STR_LIT>')<EOL><DEDENT>else:<EOL><INDENT>return self._r200<EOL><DEDENT>
Cluster Radii.

        r200 is the cluster radius within which the mean density is 200
        times the critical energy density of the universe at that z.

        :property: Returns r200 in Mpc
        :type: Quantity (1D ndarray, in astropy.units of Mpc)