Quiet-time suprathermal ions in the inner heliosphere during the rising phase of solar cycle 25

Context. The Solar Orbiter spacecraft made its first close perihelion passes in 2022, reaching 0.32 au on 26 March and 0.29 12 October. Transient activity was relatively low, making it possible to perform measurements of the quiet-time suprathermal ion pool over multi-day periods. Aims. inner heliosphere is a source seed particles accelerated by coronal mass ejection-driven shocks. Determining constituents their dependence solar activity, location, time therefore critical building physical models particle acceleration from events. Methods. By selecting low-activity periods during perihelia passes, comparing them with nearly identical monitoring instrument at 1 au, observed differences intensities can be related factors such as distance Sun, transient events, interacting wind streams. Results. Below ∼1 MeV/nucleon, spectra for H, 4 He, 3 Fe rise toward low energies, previously longer they show heavy composition that has markers impulsive flare material, high He: Fe/O ratio. proton helium abundances are much higher, consistent corotating interaction regions. Surveying all semi-quiet times mission, there only modest (∼15%) increase fluences compared indicating small gradients these populations between 0.3 au.