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We present observations of >10-100 keV/nucleon suprathermal (ST) H, He, O,and Fe ions associated with crossings of the heliospheric current sheet (HCS)at radial distances <0.1 au from the Sun. Our key findings are: 1) very fewheavy ions are detected during the 1st full crossing, the heavy ion intensitiesare reduced during the 2nd partial crossing and peak just after the 2ndcrossing; 2) ion arrival times exhibit no velocity dispersion; 3) Hepitch-angle distributions track the magnetic field polarity reversal and showup to ~10:1 anti-sunward, field-aligned flows and beams closer to the HCS thatbecome nearly isotropic further from the HCS; 4) the He spectrum steepenseither side of the HCS and the He, O, and Fe spectra exhibit power-laws of theform ~E^4-6; and 5) maximum energies EX increase with the ion's charge-to-mass(Q/M) ratio as EX/EH proportional to [(QX/MX)]^alpha where alpha~0.65-0.76,assuming that the average Q-states are similar to those measured in gradual andimpulsive solar energetic particle events at 1 au. The absence of velocitydispersion in combination with strong field-aligned anisotropies closer to theHCS appears to rule out solar flares and near-sun coronal mass ejection-drivenshocks. These new observations present challenges not only for mechanisms thatemploy direct parallel electric fields and organize maximum energies accordingto E/Q, but also for local diffusive and magnetic reconnection-drivenacceleration models. Re-evaluation of our current understanding of theproduction and transport of energetic ions is necessary to understand thisnear-solar, current-sheet-associated population of ST ions.

Suprathermal Ion Energy spectra and Anisotropies near the Heliospheric Current Sheet crossing observed by the Parker Solar Probe during Encounter 7