def X2_chain_omega_mh2(self, args):
        """
        routine to compute the log likelihood given a omega_m h**2 prior fixed
        :param args:
        :return:
        """
        H0 = args[0]
        h = H0/100.
        omega_m = self.omega_mh2_fixed / h**2
        Ode0 = self._omega_lambda_fixed
        logL, bool = self.prior_omega_mh2(h, omega_m)
        if bool is True:
            logL += self.LCDM_lensLikelihood(H0, omega_m, Ode0)
        return logL, None