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Title: Cross-Calibration of the GPS Constellation CXD Proton Data with GOES EPS

Accurate proton flux measurements of the near Earth environment are essential to the understanding of many phenomena which have a direct impact on our lives. Currently there is only a small set of satellites capable of performing these measurements which makes certain studies and analyses difficult. This paper details the capabilities of the Combined X-ray Dosimeter (CXD), flown on 21 satellites of the Global Positioning System (GPS) constellation, as it relates to proton measurements. We present a cross-calibration of the CXD with the Energetic Particle Sensor (EPS) onboard the Geostationary Operational Environmental Satellite (GOES) operated by the National Oceanic and Atmospheric Administration (NOAA). By utilizing Solar Energetic Particle Events (SEPEs) when both sets of satellites were operational we have orders of magnitude in flux and energy to compare against. Robust statistical analyses show that the CXD and GOES flux calculations are similar and that for proton energies > 30 MeV the CXD fluxes are on average within 20% of EPS. Although the CXD has a response to protons as low as 6 MeV the sensitivity at energies below 20 MeV is reduced and so flux comparisons of these are generally worse. Integral flux values > 10 MeV are typically withinmore » 40% of EPS. These calibrated CXD data sets will give researchers capabilities to study solar proton access to the inner magnetosphere down to L ~ 4 near the equatorial plane at high temporal cadence.« less
ORCiD logo [1] ; ORCiD logo [1] ; ORCiD logo [1] ;  [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); Univ. of Colorado, Boulder, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1542-7390
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Space Weather
Additional Journal Information:
Journal Volume: 16; Journal Issue: 3; Journal ID: ISSN 1542-7390
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; Heliospheric and Magnetospheric Physics
OSTI Identifier: