AMPTE/CCE observations of shell‐like He²⁺ and O⁶⁺ distributions in the magnetosheath

We present the first simultaneous observations of solar wind He 2+ and O 6+ shell‐like distributions in the magnetosheath. The He 2+ and O 6+ distributions are centered on the downstream H + bulk velocity and have radii proportional to mass/charge. These observations are consistent with the electrostatic cross‐shock potential model discussed in the text.