Spectra and cross spectra of solar wind parameters from Mariner 5

The spectra of the radial (V sub R) and nonradial (V sub T, V sub N) velocity components of the solar wind, the proton density (rho) and the proton thermal speed (W), show increasing power with increasing period up to a period of about 1 day. The powers tend to level off above 1 day except for that of V sub R which continues to increase up to a period of 10 days. At all periods, the power is V sub R is greater than that in V sub T V sub N, and W, and the difference becomes very large at the longest periods because of the increasing power in V sub R. The powers in V sub T V sub N, and W are similar at all periods. The cross spectra reveal a sharp change in behavior at periods above and below approximately 1 day, suggesting that two distant types of physical processes must dominate above and below this dividing period. In general, the coherences at the long periods are larger than at the short periods suggesting that the physical situation in the long period regime may be simpler than in the short period regime where multiple processes appear to be required to account for the low coherences.