Impacts of Ionospheric Ions on Magnetic Reconnection and Earth's Magnetosphere Dynamics

Ionospheric ions (mainly H+, He+, and O+) escape from the ionosphere and populate the Earth's magnetosphere. Their thermal energies are usually low when they first escape the ionosphere, typically a few electron volt to tens of electron volt, but they are energized in their journey through the magnetosphere. The ionospheric population is variable, and it makes significant contributions to the magnetospheric mass density in key regions where magnetic reconnection is at work. Solar wind—magnetosphere coupling occurs primarily via magnetic reconnection, a key plasma process that enables transfer of mass and energy into the near-Earth space environment. Reconnection leads to the triggering of magnetospheric storms, auroras, energetic particle precipitation and a host of other magnetospheric phenomena. Several works in the last decades have attempted to statistically quantify the amount of ionospheric plasma supplied to the magnetosphere, including the two key regions where magnetic reconnection occurs: the dayside magnetopause and the magnetotail. Recent in situ observations by the Magnetospheric Multiscale spacecraft and associated modeling have advanced our current understanding of how ionospheric ions alter the magnetic reconnection process, including its onset and efficiency. This article compiles the current understanding of the ionospheric plasma supply to the magnetosphere. It reviews both the quantification of these sources and their effects on the process of magnetic reconnection. It also provides a global description of how the ionospheric ion contribution modifies the way the solar wind couples to the Earth's magnetosphere and how these ions modify the global dynamics of the near-Earth space environment

POLICE SUSPICION AND DISCRETIONARY DECISION MAKING DURING CITIZEN STOPS*

This study examines the influence of racial, demographic and situational variables on types of police suspicion and the ancillary decision to stop and question suspects. Data were drawn from an observational study of police decision making in Savannah, Georgia. Based on the literature, we hypothesized that minority suspects will be more likely to be viewed suspiciously by the police for nonbehavioral reasons. We also hypothesize that minority status will play a significant role in the decision to stop and question suspicious persons. The findings from this study provide partial support for these hypotheses. The results indicate that minority status does influence an officer's decision to form nonbehavioral as opposed to behavioral suspicion, but that minority status does not influence the decision to stop and question suspects. We discuss the implications of these findings for understanding race and its role in police decision making