2013 - Instrument developed to measure high-energy particle fluxes around the Earth with good energy, angular and mass resolutions.
The Energetic Particle Telescope (EPT) is an instrument developed to measure the high-energy particle fluxes around the Earth with very good energy, angular and mass resolutions. EPT was launched on-board Proba-V on May 7th 2013. It measures the energy deposited by charged particles into modular sensitive elements and processes the information to identify the particles (0.2-10 MeV electrons, 4-300 MeV H and 16-1000 MeV He ions) and to determine their energy spectra and angular distribution.
Launch: May 7th, 2013
EPT Flight instrument
EPT is one of the payload instruments on the Proba-V platform. It is located in a sun-synchronous polar orbit at 820 km altitude. EPT is an unidirectional particle detector. It is oriented west in daylight and east during eclipse.
The mechanical design of EPT was driven by the scientific requirements and the demand to keep the size of the instrument to an absolute minimum.
EPT performs in flight particle discrimination. It uses a very simple counts-to-flux conversion algorithm without any spectral shape assumptions. The table below shows the energy limits for the 11 virtual EPT channels (VC) for electrons, protons and He-ions.
Energy limits (in MeV) of the virtual channels for each particle type
| VC | Electrons | Protons | He-ions |
|---|---|---|---|
| 1 | 0.5 - 0.6 | 9.5 - 13 | 38 - 51 |
| 2 | 0.6 - 0.7 | 13 - 29 | 51 - 116 |
| 3 | 0.7 - 0.8 | 29 - 61 | 116 - 245 |
| 4 | 0.8 - 1.0 | 61 - 92 | 245 - 365 |
| 5 | 1.0 - 2.0 | 92 - 126 | 365 - 500 |
| 6 | 2.0 - 8.0 | 126 - 155 | 500 - 615 |
| 7 | 8.0 - 20 | 155 - 182 | 615 - 720 |
| 8 | 182 - 205 | 720 - 815 | |
| 9 | 205 - 227 | 815 - 900 | |
| 10 | 227 - 248 | 900 - 980 | |
| 11 | > 248 | > 980 |
3D CAD model drawing of EPT on the screen and a structural model of EPT in front of the screen
Achievements that were obtained from EPT data
Proton angular distribution in the South Atlantic Anomaly
- Rotation of the satellite in a given position bin: determination of the anisotropy factor;
- Observation of the East-West asymmetry.
Solar Energetic Particle (SEP) event analysis
- Analysis of the January 2014 event as a function of time and location;
- Composition (H, He) and spectral analysis.
Radiation belt dynamics characterization
- Decay time analysis of electron fluxes after geomagnetic storm including flux enhancement;
- Analysis of the effects of big storms on the radiation belts;
- Analysis of the inner belt dynamics outside and inside the context of big storms.
More:
- EPT - Energetic Particle Telescope website (goal, partners, concept, data, observations,..)
- Radiation belts observed by PROBA-V/EPT (annual report 2021-2022)
- Radiation belts during geomagnetic storms observed by EPT (annual report 2019-2020)
- 5 years of EPT observations (annual report 2017-2018)
