Key points are not available for this paper at this time.
G. D. Zeiss, William J. Meath, J. C. F. MacDonald, D. J. Dawson, Dipole Spectrum of Water Vapor and Its Relation to the Energy Loss of Fast-Charged Particles, Radiation Research, Vol. 63, No. 1 (Jul., 1975), pp. 64-82
Zeiss et al. (1975) studied this question.