THE INTERPLANETARY EVENTS OF JANUARY-MAY, 1997 AS INFERRED FROM ENERGETIC PARTICLE DATA, AND THEIR RELATIONSHIP WITH SOLAR EVENTS

We use observations from the Goddard particle detectors on IMP 8 to in vestigate near-Earth interplanetary disturbances and the associated so lar events in January-May 1997, We infer the presence of high-speed st reams and ejecta (material in the solar wind associated with coronal m ass ejections (CMEs) at the Sun) using depressions in the counting rat e of >60 MeV/amu particles measured by the anti-coincidence guard. In addition to a sequence of high-speed streams, the guard detected four ejecta. A fifth ejecta (January 10-11), evident in solar wind observat ions, did not produce a particle decrease. During the study period the re were five particle enhancements, indicating the occurrence of energ etic CMEs at the Sun. All the particle enhancements were associated wi th halo CMEs observed by the SOHO LASCO coronagraphs. Five of the tota l of nine halo CMEs in this period impacted the Earth. None of the oth er similar to 120 CMEs detected by LASCO did so, Only the four CMEs as sociated with traditional flare signatures were also associated with > 10 MeV particle increases.