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We study the near‐relativistic (NR; >30 keV) electron event observed on 2000 February 18 by the Advanced Composition Explorer spacecraft. Highly collimated pitch‐angle distributions were observed during the first ∼2 h of the event. Roel of (2008) explained this event by assuming that the propagation of NR electrons is essentially “scatter‐free” in the inner heliosphere and that beyond 1 AU, particles are “back‐scattered” by magnetic field compressions and irregularities. We use Monte Carlo simulations to explore this approach. We fit observational sectored intensities to assure that the directional information contained in the data is used in full. We conclude that the event cannot be explained without assuming a back‐scatter region beyond 1 AU and that NR electrons propagated under weak‐scattering conditions in the inner heliosphere.

Heliospheric energetic particle reservoirs are usually observed in the decay phase of large solar energetic particle (SEP) events when particle intensities measured by widely separated spacecraft (in longitude, latitude and radial distance) present comparable intensities (within a factor of 2–3) that evolve similarly in time. We use near‐relativistic electron observations from both the ACE and Ulysses spacecraft throughout solar cycle 23 to determine when and where these reservoirs were observed by these two spacecraft. Particle reservoirs were more prominently observed during the intense active periods of November 2000 and November 2001 when Ulysses was at high (>70 deg) latitudes and at heliocentric radial distances 2.15

We examine the distribution of directions of the heliospheric magnetic field (HMF) measured by the Ulysses spacecraft during its mid‐latitude transits of the heliosphere when it observed solar wind shears from the incursions of high‐latitude fast solar wind toward the low‐latitude slow solar wind. We look for nearly radial field orientations commonly observed in rarefaction regions (i.e. where the solar wind velocity decreases monotonically over several days). In contrast to CMEs where the HMF tends to be enhanced, the rarefaction regions with nearly radial magnetic fields tend to have extremely low magnetic field magnitude values. Within these rarefaction regions, there are “dwells” in the coronal source longitude of the measured solar wind in which the time dependence of the solar wind velocity is given to a very good approximation by V(t) = R/(t‐t0), where R is the heliocentric radial distance of the spacecraft. We have therefore compiled distributions within the dwells of the parameter |Br|/B which is...