A Survey of Reconnection Signatures in Auroral Oval Ion Precipitation

The distribution function of precipitating ions on recently reconnected field lines in the auroral oval can exhibit a cutoff toward low energy due to time-of-flight effects. The cutoff energy in such signatures is usually disbursed in latitude and can be suppressed by an accelerating potential. The frequency of occurrence on the nightside is not strongly impacted by proximity to substorms. An automated procedure detects such signatures in DMSP SSJ/4 observations. A survey indicating their occurrence rate throughout the portion of the oval covered by DMSP is presented.