A Cross‐Calibrated Arase‐Van Allen Probe Phase Space Density Data Set for Studying Radiation Belt Electron Dynamics

Abstract

Determination of electron phase space density (PSD) at a wide range of L‐shells with high temporal resolution is central to understanding acceleration, transport, and loss processes in Earth's radiation belts. However, cross‐mission comparisons of PSD are complicated by instrumental biases and differing orbital coverages. In this study, we develop and validate a cross‐calibrated PSD data set combining measurements from the Arase and Van Allen Probes missions across overlapping energy ranges. Using conjunctions between Arase's MEP‐e and HEP instruments with Van Allen Probe's MagEIS instrument, we quantify systematic differences in PSD observation for fixed adiabatic invariants and derive energy channel‐specific correction functions. The cross‐calibration procedure reduces systematic biases between instruments to below 5% and leads to statistically meaningful reductions in random error, with uncertainty estimates provided for each channel. This results in a continuous combined PSD product spanning energies from 35 keV to 1.6 MeV. The resulting data set provides internally consistent cross‐mission PSD observations, extending reliable coverage of the outer belt to higher L‐shells accessible to Arase.