Paper detail

Fitting the dielectric response of collisionless plasmas by continued fractions

We present an approximation scheme for the dielectric response of thermal collisionless plasmas at arbitrary degeneracy. A T-fraction representation is obtained from the known expansions of the real part of the dielectric function for small and large arguments. The partial numerators and denominators of the continued fraction are generated by a modified Q-D algorithm. For several typical values of the degeneracy parameter $θ$, extensive tables for the expansion coefficients and the partial numerators and denominations are given allowing for an easy implementation of the fitting function. Also, an error analysis is performed.