Pitch Angle Distributions in the radiation belts are well characterized with sinnα. By tracking the exponent ‘n’, termed Pitch Angle Index, we are able to observe persistent and cross energy changes in pitch angle distributions of Van Allen radiation belt electrons using Van Allen Probes particle observations. The pitch angle distributions measurements are well fit down to a single satellite spin, and therefore can track spatially and temporally confined changes to determine connection between particles and waves. We use the Van Allen Probes data in conjunction with Geostationary Operational Environmental Satellites (GOES) spacecraft and several ground magnetometer stations from Canadian Array for Realtime Investigations of Magnetic Activity (CARISMA) and Finnish pulsation magnetometer network of Sodankylä Geophysical Observatory (SGO) to connect particles that become very anisotropic to electromagnetic ion cyclotron (EMIC) waves during a quiet period over two days, June 26 and 27, 2013. The waves and peaks in the particle PADs are both long lasting but spatially separated, suggesting that wave particle interactions in the inner magnetosphere can occur for extend periods of time and have significant impact on the global radiation belts, even during otherwise geomagnetically quiet times and when wave activity is highly localized.

We describe a novel particle telescope, the Advanced enerGetic Ion eLectron tElescope (AGILE), which utilizes full pulse shape discrimination to identify solar energetic particles (SEP), and characterizes their spectra from about 2 to 200 MeV/nuc for most species from H to Fe. AGILE is a compact, low mass, and low-power particle telescope suitable for CubeSat platforms that enable multi-point measurements in interplanetary space. AGILE will employ high heritage solid state detectors, a state-of-art high-speed sampling ASIC, as well as novel algorithms to characterize SEP to advance the understanding of charged particle energization, loss, and transport throughout the heliosphere. AGILE will resolve ion isotopes (e.g. $^3$He vs. $^4$He) with high robustness and reliability. Currently, a prototype of the instrument is being built and will be part of science payload on the GenSat-1 CubeSat. GenSat-1 is expected be launched early 2022 into a high inclination low earth orbit, with AGILE collecting data over the polar regions, i.e., the open field line regions accessed by SEP.

We present a study analyzing relativistic and ultra relativistic electron energization and the evolution of pitch angle distributions using data from the Van Allen Probes. We study the connection between energization and isotropization to determine if there is a coherence across storms and across energies. Pitch angle distributions are fit with a Jsinθ function, and the variable ‘n’ is characterized as the pitch angle index and tracked over time. Our results show that, consistently across all storms with ultra relativistic electron energization, electrons become most anisotropic within around a day of Dst and relax down to prestorm isotropization levels in the following week. In addition, each consecutively higher energy channel is associated with higher anisotropy after storm main phase. Changes in the pitch angle index are reflected in each energy channel; when 1.8 MeV electrons increase (or decrease) in pitch angle index, so do all the other energy channels. In a superposed epoch study, we show that the peak anisotropies differ between CME- and CIR- driven storms and measure the relaxation rate as the anisotropy falls after the storm. The relaxation rate in pitch angle index for CME-driven storms is -0.14+/-0.023 at 1.8 MeV, -0.28+/-0.01 at 3.4 MeV, and -0.36±0.02 at 5.2 MeV. For CIR-driven storms, the relaxation rates are -0.09±0.01 for 1.8 MeV, -0.12±0.02 for 3.4 MeV, and -0.11±0.02 for 5.2 MeV. This study shows that there is a global coherence across energies and that storm type may play a role in the evolution of electron pitch angle distributions.