\[M_{\kappa,\mu}\left(x\right)=\sqrt{x}\Gamma\left(2\mu+1\right)\kappa^{-\mu}\*%
\left(J_{2\mu}\left(2\sqrt{x\kappa}\right)+\operatorname{env}\mskip-2.0muJ_{2%
\mu}\left(2\sqrt{x\kappa}\right)O\left(\kappa^{-\frac{1}{2}}\right)\right),\]