REANALYSIS OF LAUB DRAG EFFECTS IN A RING CAVITY

Sanders and Ezekiel [J. Opt. Sec. Am. B 5, 674 (1988)] measured Laub d rag coefficients in dielectric samples moving in a ring cavity and obt ained an average difference from their theory of 60 ppm. We find signi ficant revisions to their analysis (mainly the reinterpretation of the refractive index, inclusion of angular aberration in the dispersive t erm, and corrections to the geometry of the beam path through the samp le), which increase this figure to 1290 ppm. Reasons for the residual discrepancy are advanced. Present drag measurements give direct manife stations of relativity only to an accuracy of the order of 1000 ppm. ( C) 1996 Optical Society of America.