Novel Techniques for Measuring Particles in Space
February 15, 2016
- Dr. Amy Keesee
- West Virginia University
- Surge 117A
- 4:00 p.m.
- Faculty Host: Dr. Black
Abstract: A National Space Weather Strategy and Action Plan was recently developed that includes the goals to “improve the fundamental understanding of space weather and increase the accuracy, reliability, and timeliness of space-weather observations and forecasts.” Much of our knowledge of magnetosphere dynamics, especially during space weather events, is based upon single-point measurements along the orbit of a satellite. Such measurements make it a challenge to understand and distinguish spatial and temporal variations in particle populations as well as electric and magnetic fields that occur during geomagnetically active intervals. Global measurements are required to provide measurements with both spatial and temporal resolution to fully understand the physical phenomena that occur in the magnetosphere and to validate models used to study the magnetosphere and forecast space weather events. I will present two techniques that improve our ability to observe the magnetosphere on a global scale. First, energetic neutral atom (ENA) imaging provides a remote measurement technique that provides a global view of the magnetospheric ion population through charge exchange with the geocorona. Using ENA data, we have established a technique for calculating ion temperatures that has enabled us to study ion heating during the evolution of geomagnetic storms and average ion temperatures during quiet time. Studies using this technique have demonstrated a dawn-dusk asymmetry in ion temperature, varying features in ion temperature dependent upon storm driver, and regions of ion energization injected from the magnetotail. These ion temperatures have also been used to establish storm-specific boundary conditions for inner magnetospheric modeling. Second, I will introduce our development of a next-generation plasma spectrometer. The design reduces the volume, mass, power, and voltage requirements from current plasma spectrometer technology. In addition, the manufacturing of these instruments is similar to that of computer chips, enabling large quantities of identical instruments to be easily constructed at low cost. Such an instrument will be ideal for a mission with many identical payloads to provide multiscale measurements.
Bio: Dr. Keesee received a BS in Mathematics from Davidson College and a PhD in Plasma Physics from West Virginia University. Her graduate work was primarily experimental laboratory plasma physics, studying helicon source plasmas using diagnostics such as laser induced fluorescence. As a postdoc at West Virginia University, she switched focus to magnetospheric physics. She is currently a research assistant professor at WVU.