Solar Orbiter's Energetic Particle Detector (EPD)
Solar Orbiter is ESA's next heliospheric mission, foreseen for launch in
January 2017. Solar Orbiter's primary science goal is to understand how
the Sun creates and controls the heliosphere, this giant plasma bubble
carved out of the interstellar medium by the supersonically expanding
solar wind. ESA is providing the spacecraft, mission operations, and two
facility instruments, SPICE and SIS, while the ESA memeber states provide
most of the remaining payload. NASA provides the launcher, an Atlas V, and
two instruments, Solo-HI, and SWA-HIS.
The Institute for Experimental and Applied Physics (IEAP) of the
Christian-Albrechts-University (CAU) is developing four sensors for the
Energetic Particle Detector (EPD), the SurparThermal Electron Ion and
Neutral (STEIN) sensor, the Electron-Proton Telescope (EPT), the
High-Energy Telescope (HET), and the Suprathermal Ion Spectrograph (SIS).
The build and development of STEIN, EPT, and HET is funded through
the German space agency,DLR, and SIS is funded by ESA as a facility
instrument.
Click me: a video to the project
The Energetic Particle Detector (EPD) suite consists of five sensors measuring electrons, protons, and ions from helium to iron, and operating at partly overlapping energy ranges from 2 keV up to 200 MeV/n. The EPD sensors and a common data processing unit with low voltage power supply are:
- SupraThermal Electrons, Ions, and Neutrals (STEIN)
- SupraThermal Ion Spectrograph(SIS)
- Electron Proton Telescope (EPT)
- Low Energy Teelscope (LET)
- High Energy Telescope (HET)
- Instrument Control Unit (ICU)
Figure: EPD instrument funtional diagramm
The EPD sensors share the Instrument Control Unit (ICU) that is composed by the
Common Data Processing Unit and the Low Voltage Power Supply (CDPU/LVPS),
which is the sole power and data interface of EPD to the spacecraft.
STEIN consists of a single unit having two view cones in opposite directions. SIS
consists of two sensor heads with roughly opposite (160°) view directions sharing a
common electronics box. EPT-HET has multiple view cones sharing a common
electronics box. There are two identical EPT-HET units. LET has multiple view cones
and consists of two separate identical units.
The overall energy coverage achieved with the EPD sensors is 0.002 MeV to 20 MeV
for electrons, 0.003 MeV to 100 MeV for protons, 0.008 MeV/n to 200 MeV/n for
heavy ions (species-dependent).
Figure: EPD energy coverage
