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  • 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

  • Radiation belts are hazardous regions found around several of the planets in our Solar System. They consist of very hot, electrically charged particles that are trapped in the magnetic field of the planet. At Saturn the most important way to heat these particles has for many years been thought to involve the particles drifting closer towards the planet. This paper builds on previous work on the emerging idea at Saturn that a different way to heat the particles is also possible where the heating is done by waves, in a similar way to what we find at the Earth. This work is reported in the paper "Acceleration of electrons by whistler-mode hiss waves at Saturn" by E.E. Woodfield et al., 2021. The data provided here enable reconstruction of all the figures in the paper. E.E.W., R.B.H., and S.A.G. were funded by STFC grant ST/S000496/1. R.B.H., S.A.G. and A.J.K. were funded by NERC grant NE/R016038/1 and R.B.H. and S.A.G. by NERC grant NE/R016445/1. J.D.M. and Y.Y.S. were supported by NASA grants NNX11AM36G and NNX16AI47G. University of Iowa (J.D.M.) was supported by NASA contract 1415150 with JPL. Y.Y.S. was supported by EC grant H2020 637302.

  • These data include pitch angle diffusion coefficients for chorus waves which have been evaluated at the angle of loss cone calculated in multiple ways. We have predominately concentrated on the dawnside between 00-12 MLT (Magnetic Local Time), for 5<L*<5.5 as this is where we have Van Allen Radiation Belt Storm Probes (RBSP) measurements and scattering of electrons due to chorus waves is known to occur. We have used 7 years of RBSP wave and cold plasma measurements between November 2012 to October 2019 to calculate these diffusion coefficients. For the first two sets of data we provide chorus diffusion coefficients with fpe/fce times by 2 and divided by 2 respectively. The next four data sets have been calculated from RBSP data using two different methods, first using average values, as has previously been done (e.g. Horne et al [2013]) and used above, and secondly by using co-located measurements of the wave spectra and fpe/fce to calculate pitch angle diffusion coefficients (Daa), where fpe is the plasma frequency and fce is the proton gyro frequency, and then averaging, similar to that presented in Ross et al [2021] for Electromagnetic Ion Cyclotron (EMIC) waves and Wong et al [2022] for magnetosonic waves. Both methods use a modified version of the PADIE code Glauert et al [2005] which allows an arbitrary wave power spectral density input rather than Gaussian inputs. The RBSP chorus diffusion coefficient matrices are computed by combining RBSP data with a profile for how chorus wave power changes with latitude, derived from the VLF database in Meredith et al [2018]. The magnetic latitude profile enables us to map RBSP measurements to magnetic latitudes between 0<MLAT<60 and therefore include the effects of high latitude chorus in our results. The RBSP diffusion matrices also use a new chorus wave normal angle model derived from RBSP data composed of different wave normal angle distributions for different spatial location and fpe/fce bins. Lastly we include two data sets of RBSP-chorus diffusion coefficients combined with diffusion coefficients due to collisions with atmospheric particles to calculate the total diffusion of electrons near the loss cone between 00-12 MLT, for 5<L*<5.5. We have produced these different sets of chorus (and combined chorus and collision) diffusion coefficients to test our methods of calculating electron precipitation and find what variables these calculations are sensitive to. Funding was provided by NERC Highlight Topic Grant NE/P01738X/1 (Rad-Sat) and NERC National Capability grants NE/R016038/1 and NE/R016445/1

  • 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

  • Radiation belts are hazardous regions found around several of the planets in our Solar System. They consist of very hot, electrically charged particles that are trapped in the magnetic field of the planet. At Saturn the most important way to heat these particles has for many years been thought to involve the particles drifting closer towards the planet. This paper adds to the emerging idea at Saturn that a different way to heat the particles is also possible where the heating is done by waves, in a similar way to what we find at the Earth. This work is reported in the paper "Rapid electron acceleration in low density regions of Saturn''s radiation belt by whistler mode chorus waves" by E.E. Woodfield et al., 2019. The data provided here enable reconstruction of all the figures in the paper. The research leading to these results has received funding from: Natural Environment Research Council (NERC), UK, grants NE/R016038/1 and NE/R016445/1 Science and Technology Facilities Council (STFC), UK, grants ST/I001727/1 and ST/M00130X/1. NASA grants NNX11AM36G and NNX16AI47G. The research at the University of Iowa was supported by NASA through Contract 1415150 with the Jet Propulsion Laboratory. European Council (EC) grant H2020 637302.

  • 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