A new series for approximating Voigt functions

. A Voigt function is the convolution of a Gaussian and a Cauchy, or Lorentzian, density. The computation of these functions is required in problems arising in a variety of subjects such as nuclear reactors, atmospheric transmittance, and spectroscopy. This letter presents a new series for the approximate computation of Voigt functions. The derivation is accomplished using straightforward Fourier techniques, and it yields computable error bounds between the approximation and the Voigt function. The approach also permits a simple derivation of an asymptotic expansion for large argument values. PACS number: 02.60.--x 1. Introduction T HE convolution of a Gaussian probability density and a Cauchy, or Lorentzian, probability density is known as a Voigt function. Because Voigt functions arise in many different contexts, such as nuclear reactor theory, atmospheric transmittance, and spectroscopy, there has been much interest in computing them, e.g., [1], [4]--[11]. In the present letter w...