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Suprathermal ions in the corona are thought to serve as seed particles forlarge gradual solar energetic particle (SEP) events associated with fast andwide coronal mass ejections (CMEs). A better understanding of the role ofsuprathermal particles as seed populations for SEP events can be made by usingobservations close to the Sun. We study a series of SEP events observed by theIntegrated Science Investigation of the Sun (IS$\odot$IS) suite on board theParker Solar Probe (PSP) from 2020 May 27 to June 2, during which PSP was atheliocentric distances between $\sim$0.4 and $\sim$0.2 au. These events werealso observed by the Ahead Solar TErrestrial RElations Observatory (STEREO-A)near 1 au, but the particle intensity magnitude was much lower than that atPSP. We find that the SEPs should have spread in space as their source regionswere distant from the nominal magnetic footpoints of both spacecraft, and theparent CMEs were slow and narrow. We study the decay phase of the SEP events inthe $\sim$1-2 MeV proton energy range at PSP and STEREO-A, and discuss theirproperties in terms of both continuous injections by successive solar eruptionsand the distances where the measurements were made. This study indicates thatseed particles can be continuously generated by eruptions associated with slowand narrow CMEs, spread over a large part of the inner heliosphere, and remainthere for tens of hours, even if minimal particle intensity enhancements weremeasured near 1 au.

Widespread 1-2 MeV Energetic Particles Associated with Slow and Narrow Coronal Mass Ejections: Parker Solar Probe and STEREO Measurements