A STATISTICAL STUDY OF THE 164 DAY CLOCK NOISE OF THE RELATIVISTIC BEAMS IN SS-433

We have estimated the epochs of the phases of maximal red and blue bea m Doppler shifts for various cycles of the approximately 164d period i n SS 433, using an updated optical spectroscopic data base, which cove rs a time span of over 13 years. By constructing power density spectra of phase residuals based on these epochs (residuals measured relative to a hypothetical clock with constant period), we are able to charact erize the statistical behavior of the clock noise in both the red and blue beam 164d cycles as a white noise process in the first time deriv ative of 164d phase fluctuations (i.e., as a white noise process in fr equency, or equivalently, as a random walk in 164d phase). Our charact erizations of the 164d clock noise in SS 433 show a strong, quantitati ve similarity to the previously characterized clock noise of the 35d p eriodicity of x-ray turn-ons in Her X-1, lending further credence to t he notion that the relevant underlying physical process in both system s is disk precession.