Compact Full-Field Ion Detector System (CFIDS)
Sensors
Compact Full-Field Ion Detector System (CFIDS) (LEW-TOPS-142)
A next-generation space radiation monitoring system designed to function in a variety of locations and conditions in space.
Overview
Space radiation, or "space weather" comes in different forms from a variety of sources. High energy X-rays, gamma rays, and other ionizing radiation, in the form of subatomic particles and ionized atoms, can be produced by black hole activity, new star formation, and even via lightning from thunderstorms.
Most of the radiation from space that reaches the earth is generated by our sun, in the form of the solar wind, solar flares, and coronal mass ejections. One of the ways in which the sun releases charged particles from its corona (outer atmosphere) is in the the solar wind. Interaction between the sun’s magnetic field, the solar wind, and the earth’s magnetic field can lead to magnetic disturbances of the earth’s magnetic field known as geomagnetic storms.
Impacts of Space Radiation: High-energy radiation from space can damage electric components on satellites, space stations, and high-altitude aircraft. This damage can disrupt functionality and communication and may also lead to complete failure of those components. Ionizing radiation also leads to the slow degradation of materials that structures in space are made from. It can cause damage to DNA of astronauts and high-altitude aircraft pilots and crew.
This same ionizing radiation interacts with the magnetic fields and atmospheres of planets such as the earth that have magnetic fields and atmospheres. It can disrupt radio signals, communications signals, and electrical grid performance on earth.
The Technology
The CFIDS is a modular system, which consists of multiple types of detectors that work either together or separately to monitor different types of radiation from multiple directions at once.
CFIDS measures high-energy charged particles using solid-state charged particle telescopes based on Silicon Carbide Micro-electromechanical Systems (MEMS) technology. Silicon carbide devices are more resistant to damage from the radiation in space than other candidate detector materials and exhibit steady operation over a very wide range of temperatures, and they have the same operating characteristics in bright sunlight as in shaded areas, unlike other electrical devices in space.
The CFIDS also has a central scintillation detector for high energy cosmic rays, and scintillation detectors for lower energy particles that can also be used as start/stop indicators for data collection.
These characteristics allow the CFIDS to provide accurate information in a wide variety of circumstances for longer periods of time. The CFIDS detector system, or one or more of its components can be positioned on satellites, landers, rovers, or planetary base structures to monitor the local space weather environment and report conditions to a network that can prepare systems and people for changes in space weather.
The CFIDS is an integrated package comprised of a central spherical Cherenkov detector surrounded by compact detector stacks. The Spherical Geometry: LEW-18362-1 of the integrated system resembles the shape of a soccer ball. These stacks utilize arrays of Compact Large Area Charged Particle Telescopes: LEW-20486-1 made from silicon carbide (SiC) and engineered to be extremely compact, with prototypes measuring less than four centimeters wide.
A key innovation is the replacement of conventional, fragile glass photomultiplier tubes (PMTs) with a patented solid-state, Low-power Charged Particle Detector: LEW-19171-1 allowing for operating in harsh and low-power environments. This is achieved using a Fast, Large-area, Wide-Bandgap (WBG) UV photodetector: LEW-19040-1. This photodetector is fabricated on a commercially available, single-crystal zinc oxide (ZnO) substrate and can detect the full range of UV light in two nanoseconds or less. By carefully matching the light emitted from the scintillator with the sensitivity of the UV-sensitive photodiode, the system eliminates the need for both high-voltage PMTs and efficiency-reducing wave shifters. This solid-state design makes the entire system smaller, lighter, and more power-efficient, allowing it to be integrated into platforms with significant size and power constraints, such as CubeSats.
Benefits
- Solid-state charged particle telescope components are based on Silicon Carbide MEMS technology, making them more resistant to damage from the radiation in space than other detector materials.
- CFIDS components exhibit steady operation over a very wide range of temperatures, and they have the same operating characteristics in bright sunlight as in shaded areas, unlike other electrical devices in space.
- The CFIDS detector system of one of its modular components can be positioned on satellites, landers, rovers, or planetary base structures to monitor the local space weather environment and report conditions to a network that can prepare systems and people for changes in space weather.
Applications
- Satellites and deep space platforms
- In-situ measurements of space plasma environments and galactic cosmic radiation
- Radiation dosimetry aboard high altitude aircraft
Technology Details
Sensors
LEW-TOPS-142
LEW-18362-1
LEW-18362-2
LEW-20486-1
LEW-19171-1
LEW-19040-1
See also LEW-TOPS-71 “Low-Power Charged Particle Detector”.
John D. Wrbanek, Gustave C. Fralick, Susan Y. Wrbanek: “Directional Spherical Cherenkov Detector,” NASA Tech Briefs, April 2010, p. 7-8. LEW-18362-1. NTRS ID 20100012816 https://ntrs.nasa.gov/citations/20100012816.
John D. Wrbanek, Susan Y. Wrbanek, “Fast, Large area, Wide Band GAP UV Photodetector for Cherenkov Light Detection,” NASA Tech Briefs, October 2013, LEW-19040-1. NTRS Document ID 20140002261 https://ntrs.nasa.gov/citations/20140002261.
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