Calibration of the GOES 13/15 high‐energy proton detectors based on the PAMELA solar energetic particle observations

Abstract

The Energetic Proton, Electron, and Alpha Detector (EPEAD) and High Energy Proton and Alpha Detector (HEPAD) instruments on the Geostationary Operational Environmental Satellite (GOES) spacecraft have served over many years as monitors of the solar particle intensities, surveying the Sun and measuring in situ its effect on the near‐Earth solar‐terrestrial environment. However, the reconstruction of the differential energy spectra is affected by large uncertainties related to the poor energy resolution, the small geometrical factor, and the high contamination by out‐of‐acceptance particles. In this work, the high‐quality data set from the Payload for Antimatter Matter Exploration and Light‐nuclei Astrophysics (PAMELA) space mission is used to calibrate the high‐energy (>80 MeV) proton channels of the EPEAD and the HEPAD sensors on board the GOES 13 and 15, bringing the measured spectral intensities inline with those registered by PAMELA. Suggested corrections significantly reduce the uncertainties on the response of GOES detectors, thus improving the reliability of the spectroscopic observations of solar energetic particle events.

Solar Cosmic Ray Dose Rate Assessments During GLE 72 Using MIRA and PANDOCA

“…Here the results from the double power law fit are presented. To derive the proton spectra, the GOES data were used with the recalibrated energy channels from Bruno () as further elaborated in Matthiä et al (). In this recalibration, the highest energy channels of the HEPAD instruments have mean energies of 1002.4 MeV (GOES‐13) and 1094.7 MeV (GOES‐15).…”

The Solar Particle Event on 10–13 September 2017: Spectral Reconstruction and Calculation of the Radiation Exposure in Aviation and Space

“…Measurements of the Electron, Proton and Alpha Detector (EPEAD) and the High‐Energy Proton and Alpha Detector (HEPAD) instruments onboard GOES‐15 (Rodriguez et al, ) were used to reconstruct the differential energy spectra during the event. The calibration of the GOES energy channels provided by Bruno () was applied. The recorded GOES data were averaged over 1‐hr periods starting on 10 September 2017 16:30 UTC until 12 September 2017 22:30 UTC, which corresponds to 54 time intervals.…”

“…Nominally the B detector looks west and the A detector east, but this relationship reverses when the spacecraft is inverted (so‐called “yaw flip”; for details see Rodriguez, ; Rodriguez et al, ). Accordingly, for the analysis in this work the westward facing detector (A for GOES‐15) was selected and the corresponding energy calibration provided by Bruno () was used. The differences in the calibration of the A and B detectors, however, are in the percent region only.…”

“…The differences in the calibration of the A and B detectors, however, are in the percent region only. The lowest and highest energy channels used in this analysis were the EPEAD P3 channel (nominal energy range 9–15 MeV) and the HEPAD P11 channel (nominal energy range > 700 MeV, recalibrated 1094 MeV; Bruno, ). As the EPEAD data provided by NOAA are already background corrected, only in the HEPAD data was the background removed using the preevent average between 10 September 2017 00:00 UTC and 16:00 UTC.…”

Model of Energy Spectrum Parameters of Ground Level Enhancement Events in Solar Cycle 23

“…The inaccuracy can be assumed to be caused by some local structure effects, for example, magnetospheric effects, which are not very strong for protons > 10 MeV normally. Figure 18 shows, for GLE71 of solar cycle 24, the comparison between the modeling results and the observations from ACE/EPAM (energy ranging from ∼0.1 to ∼3 MeV) and GOES 13 differential channels (channels P6-P7, energy ranging from 113.3 to 178.5 MeV, calibrated by Bruno, 2017), and integral channels (> 5, > 10, > 30, > 50, > 60, and > 100 MeV, described in Mewaldt et al, 2005). It is shown that generally the modeling results agree well with observations for GLE71, except that in lower-energy range the intensity from observations, marked in red, is relatively higher than that from modeling.…”