Since its launch in 2018, the Integrated Science Investigation of the Sun (IS⊙IS) instrument suite on Parker Solar Probe has observed numerous periods of 3 He-rich solar energetic particle (SEP) events. Notable among them are some very small events that occurred on 21 January 2021 and 30 May 2022, in both cases when Parker was within 0.2 AU of the Sun. In these events the 3 He/ 4 He ratio was greater than 10 at ∼1 MeV/nucleon but rapidly decreased with increasing energy since 3 He had softer spectra than 4 He. Although unusual, similar extreme enrichments of 3 He have occasionally been observed at 1 AU in other events. The events seen by Parker were anisotropic, had velocity dispersion yielding inferred pathlengths longer than expected for scatter-free transport along a nominal Parker spiral, and were associated with type III radio emission detected by Parker/FIELDS. We present the Parker observations of the time profiles, spectra, composition, velocity dispersion, and anisotropies of these events and compare them with previous 3 He-rich SEP events detected much farther from the Sun.
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