Approximate scaling formula for collisional angular-momentum mixing of Rydberg atoms

An approximate scaling formula has been determined that permits the rapid estimation of cross sections for angular-momentum-changing collisions of Rydberg atoms with a variety of targets, using information about low-energy-electron scattering from the target. The formula is obtained by fitting the results of coupled-channel and Born-approximation calculations to functions of reduced parameters. Application to Na(nd) + He, Ne, Ar, N₂, CH₄, C₃{H}₈$; $Rb(nf)$ + He, Ar, Xe; and $Xe(nf)$ + C${O}₂$, suggests that the accuracy is about a factor of 2.