A cosmic-ray observatory is a scientific installation built to detect high-energy-particles coming from space called cosmic rays. This typically includes photons (high-energy light), electrons, protons, and some heavier nuclei, as well as antimatter particles. About 90% of cosmic rays are protons, 9% are alpha particles, and the remaining ~1% are other particles.
It is not yet possible to build image forming optics for cosmic rays, like a Wolter telescope for lower energy X-rays,[1][2] although some cosmic-ray observatories also look for high energy gamma rays and x-rays. Ultra-high-energy cosmic rays (UHECR) pose further detection problems. One way of learning about cosmic rays is using different detectors to observe aspects of a cosmic ray air shower.
Methods of detection for gamma-rays:[3]
- Scintillation detectors
- Solid state detectors
- Compton scattering
- Pair telescopes
- Air Cherenkov detectors
For example, while a visible light photon may have an energy of a few eV, a cosmic gamma ray may exceed a TeV (1,000,000,000,000 eV).[3] Sometimes cosmic gamma rays (photons) are not grouped with nuclei cosmic rays.[3]
- ^ Wolter, H. (1952). "Glancing Incidence Mirror Systems as Imaging Optics for X-rays". Annalen der Physik. 10 (1–2): 94–114. Bibcode:1952AnP...445...94W. doi:10.1002/andp.19524450108.
- ^ Wolter, H. (1952). "Verallgemeinerte Schwarzschildsche Spiegelsysteme streifender Reflexion als Optiken für Röntgenstrahlen". Annalen der Physik. 10 (4–5): 286–295. Bibcode:1952AnP...445..286W. doi:10.1002/andp.19524450410.
- ^ a b c GSFC Gamma-Ray Telescopes & Detectors