Evaporative ion cooling in SSX*

Reconnection of merged plasmas in SSX results in rapid heating of ions and electrons. The SSX ion Doppler spectrometer shows heating of carbon and helium ions up to $100~eV$ in a new slightly prolate flux conserver ($R=0.2~m, L=0.4~m$). A particle orbit simulation in realistic SSX magnetic fields shows that energetic ions are rapidly lost to the walls leaving behind a cooler ion population. We refer to this phenomenon as evaporative ion cooling. A retarding grid energy analyzer and a Mach probe are being used to study energetic ion flux and high velocity flows. Both probes are $\sim1.5~cm$ in diameter and can be scanned across the radius of the device at the mid-plane. Following reconnection, local flow speeds of greater than $60~km/s$ (Mach number $>2$) have been measured by the Mach probe in the present geometry. Preliminary data indicates bi-directional outflows during merging shots. Energetic ion data will be presented if available. The particle orbit code is being used to simulate $\sim10^6$ particles with random initial conditions in SSX. The simulation traces particle orbits and models the probe structure in order to generate predictions of actual probe signals.