Cosmic ray variations and turbulent flow systems: 0.3-1.0 AU; 1977-1980

Relations among the relative counting rates of cosmic ray protons and the magnetic fields and flows observed by Helios 1 between 0.3 AU and 1 AU in the period January 1977 to August 1980 are discussed. Isolated corotating or transient flows are associated with short-term depressions in cosmic ray intensity, but the effects are localized in longitude. Systems of corotating streams do not produce a long-term modulation effect, although temporary, short-term depressions in cosmic ray intensity are associated with individual streams and interaction regions. Spectra of fluctuations of the magnetic field and magnetic helicity for systems of corotating flows often do not have the form f-5/sup //3 at frequencies > or =10-5 Hz, and accordingly, the hydromagnetic fluctuations in corotating streams near the sun do not appear to represent fully developed turbulence at low frequencies. Systems of transient streams containing shocks that might encircle the sun are associated with long-lasting decreases in cosmic ray intensity. The magnetic field fluctuations in such flow systems are often turbulent, with f-5/sup //3 spectra extending from below 10-5 Hz to the Nyquist frequency of the data. The turbulence is likely to be confined to sheets with thickness of the order of 0.1 AU, possibly associated with shocks. We conclude that long-term modulation of cosmic rays inside 1 AU is associated with turbulence in transient disturbances that probably encompass a large longitudinal extent around the sun. In mixed flow systems the effects are intermediate between those of corotating and transient systems. The net modulation may be relatively small, with large short-term variations associated with individual streams