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  • Relativistic electrons in the Earth''s outer radiation belt are a significant space weather hazard. Satellites in GPS-type orbits pass through the heart of the outer radiation belt where they may be exposed to large fluxes of relativistic electrons. In this study we conduct an extreme value analysis of the daily average relativistic electron flux in GPS orbit as a function of energy and L using data from the US NS41 satellite from 10 December 2000 to 25 July 2020. The 1 in 10 year flux at L=4.5, in the heart of the outer radiation belt, decreases with increasing energy ranging from 8.2x10^6 cm^-2s^-1sr^-1MeV^-1 at E = 0.6 MeV to 33 cm^-2s^-1sr^-1MeV^-1 at E = 8.0 MeV. The 1 in 100 year is a factor of 1.1 to 1.7 larger than the corresponding 1 in 10 year event. The 1 in 10 year flux at L=6.5, on field lines which map to the vicinity of geostationary orbit, decrease with increasing energy ranging from 6.2x10^5 cm^-2s^-1sr^-1MeV^-1 at E = 0.6 MeV to 0.48 cm^-2s^-1sr^-1MeV^-1 at E = 8.0 MeV. Here, the 1 in 100 year event is a factor of 1.1 to 13 times larger than the corresponding 1 in 10 year event, with the value of the factor increasing with increasing energy. Our analysis suggests that the fluxes of relativistic electrons with energies in the range 0.6 <= E <= 2.0 MeV in the region 4.25 <= L <= 4.75 have an upper bound. In contrast, further out and at higher energies the fluxes of relativistic electrons are largely unbounded. The research leading to these results has received funding from the Natural Environment Research Council (NERC) grants NE/V00249X/1 (Sat-Risk) 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.

  • This dataset contains two NetCDF files: Chorus_daa.nc (labelled from here as a) which contains the chorus pitch angle diffusion coefficients presented in Figure 1 of Reidy et al (2020) and Combined_daa.nc (labelled from here as b) containing the combined pitch angle diffusion coefficients which can be used to do the analysis presented in the remainder of the Reidy et al (2020) paper. These data sets include: a. A matrix containing the pitch angle diffusion coefficients for chorus waves at the angle of the loss cone for energies of 30, 100 and 300 keV between L*= 2-7.5, a full range of MLT sectors and for low (1 < Kp < 2), moderate (2 < Kp < 3) and high (4 < Kp < 7) geomagnetic activity levels. These were calculated from an average wave model presented in Meredith et al (2020) to capture the effect of wave-particle interactions in the BAS Radiation Belt Model (BAS-RBM). Also the arrays containing the energy, L*, MLT and Kp dependence are also included. b, A matrix containing the combined pitch angle diffusion coefficients for chorus, hiss and EMIC waves and coulomb collisions between alpha = 0.5deg -9.45deg, Energy = 28.18-2511.89 keV , L* = 4.25-7.25, MLT = 0-24 and 6 different activity levels. The arrays containing the pitch angle, energy, L*, MLT and Kp dependence are also included. Funding was provided by NERC Highlight Topic Grant NE/P01738X/1 and NERC National Capability grants NE/R016038/1 and NE/R016445/1

  • The data provided is the underlying data used for creating the plots in Ross et al 2020. The research leading to these results has received funding from the National Environment Research Council Highlight Topic grant NE/P01738X/1 (Rad-Sat), National Environment Research Council grant NE/R016445/1 and NE/R016038/1, and the STFC grant ST/S000496/1

  • The SaRIF system forecasts the outer electron radiation up to 24 hours ahead, updated every hour. Risk indicators are provided for four satellite orbits and can be compared against design standards The SaRIF system provides a searchable archive of data for anomaly resolution by satellite operators, designers and underwriters. Funding was provided by ESA contract 4000118861/16/D/MRP (SSA P2-SWE-XIII proto-type)

  • This data is provided to comply with the AGU''s data policy for the publication of Glauert et al., "Evaluation of SaRIF high-energy electron reconstructions and forecasts" in Space Weather, 2021. Each data file corresponds to a figure or table in the paper and covers the period from 1 March 2019 to 1 September 2019. The data sets are as follows: Figure 1 - SaRIF reconstructions of the >800 keV and the >2 MeV flux (in cm-2 s-1 sr-1) measured by the GOES 14 spacecraft. Figure 3 - SaRIF 24-hour forecasts of the >800 keV and the >2 MeV flux (in cm-2 s-1 sr-1) at the location of the GOES 14 spacecraft. Figure 5 - SaRIF reconstructions of the >800 keV and the >2 MeV flux (in cm-2 s-1 sr-1) measured by the GOES 14 spacecraft, with the improvements to the modelling detailed in the paper. Figure 6 - Simulated SaRIF 24-hour forecasts of the >800 keV and the >2 MeV flux (in cm-2 s-1 sr-1) at the location of the GOES 14 spacecraft, with the improvements to the modelling detailed in the paper. Table 6 - Simulated SaRIF 24-hour reconstructions and forecasts of the >800 keV and the >2 MeV flux (in cm-2 s-1 sr-1) at the location of the GOES 14 spacecraft when the outer boundary for the simulation is placed at L* = 6.6. These are the values used to produce the metrics in Table 6. This research was supported by the Natural Environment Research Council (NERC) Highlight Topic Grant NE/P01738X/1 (Rad-Sat), National and Public Good activity grant NE/R016445/1 and ESA contract 4000118861/16/D/MRP (SSA P2-SWE-XIII proto- type)

  • Signals from VLF transmitters can leak from the Earth-ionosphere wave guide into the inner magnetosphere, where they propagate in the whistler mode and contribute to electron dynamics in the inner radiation belt and slot region. Observations show that the waves from each VLF transmitter are highly localised, peaking on the nightside in the vicinity of the transmitter. In this study we use ~5 years of Van Allen probe observations to construct global statistical models of the bounce-averaged pitch angle diffusion coefficients for each individual VLF transmitter, as a function of L*, Magnetic Local Time (MLT) and geographic longitude. We construct a 1D pitch-angle diffusion model with implicit longitude and MLT dependence to show that VLF transmitter waves weakly scatter electrons into the drift loss cone. We find that global averages of the wave power, determined by averaging the wave power over MLT and longitude, capture the long-term dynamics of the loss process, despite the highly localised nature of the waves in space. We use our new model to assess the role of VLF transmitters waves, hiss waves, and Coulomb collisions on electron loss in the inner radiation belt and slot region. At moderate relativistic energies, E~ keV, waves from VLF transmitters reduce electron lifetimes by an order of magnitude or more, down to the order of 200 days near the outer edge of the inner radiation belt. However, VLF transmitter waves are ineffective at removing multi-MeV electrons from either the inner radiation belt or slot region. Funding was provided by the NERC grant NE/P01738X/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