The heliosphere is permeated by several species of suprathermal and energetic particles (protons, electrons, heavy ions), exhibiting a diverse range of energy spectra and originating at different heliospheric and interstellar locations. Such energetic particles are of paramount importance to address many unconstrained aspects of energy conversion in astrophysical systems, as well as being impactful to society as they can pose a hazard to both human activities and technological systems in space. Suprathermal particles, in particular, are a key population that bridges the low-energy (1 keV in the heliosphere) plasma and hi-energy (> 1 MeV) population, often treated independently.

The dynamics of suprathermal and energetic particles in the heliosphere encompass various processes, from the acceleration of solar wind electrons/ions to impulsive and gradual solar energetic particles events related to solar eruptive phenomena. Despite decades of research, several aspects of suprathermal and energetic particle production remain unknown, with the main candidate production mechanisms being magnetic reconnection, collisionless shocks and several categories of wave-particle interactions. How suprathermal and energetic particles are transported through the heliosphere is also object of active debate, and largely unconstrained. Recent missions, such as Solar Orbiter and Parker Solar Probe, have delivered excellent observations from the inner heliosphere, both remotely and in situ. When combined with data from missions like ACE, SOHO, Wind, and STEREO at 1 AU, these observations across varying radial distances offer an unprecedented opportunity to characterize the sources and transport mechanisms of suprathermal and energetic particles in the heliosphere.

This session invites contributions that explore space-borne and ground-based observations, as well as theoretical and modelling approaches, to deepen our understanding of the acceleration and transport of suprathermal and energetic particles in the heliosphere. We encourage submissions that provide new insights, propose innovative methodologies, or synthesize data across multiple missions to address these critical scientific challenges.