On the evaluation of H and X functions

We indicate a Double Exponential Formula based numerical integration method for the evaluation of the Ambarzumian–Chandrasekhar H function and the X   function of neutron transport for the single speed and isotropic case. This method is significantly more economical than our earlier scheme, which was based on IMT quadrature. For c<5c<5, the present method converges faster than our earlier IMT scheme. This will be adequate for all radiative transport and transport theory applications. These findings are supported by appropriate error analysis. Unlike the IMT method, the DE quadrature nodes are generated by a simple algebraic expression which is a great advantage.