HIGH-ENERGY COSMIC-RAY NUCLEI RESULTS ON ULYSSES .2. EFFECTS OF A RECURRENT HIGH-SPEED STREAM FROM THE SOUTHERN POLAR CORONAL HOLE

Since June 1992 the Kiel Electron Telescope on board ULYSSES measures 26-day variations of the order of 6% in the fluxes of high energy H an d He. In May 1993 ULYSSES entered into the unipolar region of the sout hern polar coronal hole, but continued to observe similar effects: inc reases in the MeV proton channels due to acceleration near the shocks of the corotating interaction region and decreases in the intensity of galactic nuclei associated with the same region. Amplitude variations are presented for different magnetic rigidities and the effects are d iscussed in view of corotating shock development in a 3-dimensional he liospheric structure.