Drift-averaged pitch angle diffusion coefficients, and derived pitch angle distributions and loss timescales for electrons with energies from 100 keV to 4 MeV, L* in the range 2 to 7 and geomagnetic activity determined by the Kp index. The pitch angle distributions and loss timescales, for use in radiation belt models, are calculated from the diffusion coefficients assuming pure pitch angle diffusion and steady decay of the distribution. Funding was provided by NERC grant NE/V00249X/1 (Sat-Risk)

Electromagnetic Ion Cyclotron (EMIC) wave are important for the losses of ultra-relativistic electrons from the Earth''s radiation belts. In this work, statistical EMIC diffusion coefficients are calculated from Van Allen Probe A observations of EMIC waves from the entire mission. The diffusion coefficient calculations include the observed L* and activity dependent distributions in plasma density and wave spectra so that the wave-particle interactions modelled are representative of those in the radiation belts. These diffusion coefficients can be included into global radiation belt simulations such as the BAS radiation belt model. The study is published in Ross et al 2021, JGR: Space Physics. Funding was provided by National Environment Research Council Highlight Topic grant NE/P01738X/1 (Rad-Sat), National Environment Research Council grant NE/R016445/1 and NE/R016038/1.

Two model runs using the BAS Radiation belt model; one using a low energy boundary condition set from POES data, another using a low energy boundary condition from Van Allen Probes MagEIS data. The outer boundary condition and inner boundary have been set by Van Allen Probes data for both runs. The electron flux for an equatorial pitch angle of 90 degrees is supplied for 0.9 MeV electrons. Both runs cover a period from the 3rd - 28th June 2013. Funding was provided by the NERC grant NE/L002507/1.

The banded structure of Electromagnetic Ion Cyclotron (EMIC) wave spectra and their resonant interactions with radiation belt electrons depend on the cold ion composition. However, there is a great deal of uncertainty in the composition in the inner magnetosphere due to difficulties in direct flux measurements. Here we determine the sensitivity of electron diffusion by EMIC waves to the cold ion composition. The diffusion coefficients are calculated using collocated EMIC waves spectra and plasma densities observed by Van Allen Probe Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) data, parameterised by Dst, using quasi-linear theory implemented in the Pitch-Angle Diffusion of Ions and Electrons (PADIE) code. Funding was provided by NERC Highlight Topic grant: NE/P01738X/1 (Rad-Sat), NERC grant: NE/V00249X/1 (Sat-Risk) and NERC grant: NE/R016038/1