(very-high-energy particles from beyond the solar system)
Cosmic rays are high energy particles,
with typical energies up to about
0.3 GeV (4.8 × 10-11 joule),
but the highest energy have been
up to 3 × 1011 GeV.
The term was coined when detectors were developed
that demonstrate they continually fall on Earth,
and the term traditionally means both photons
(photon ray or photonic ray)
and atomic nuclei (fermion ray or fermionic ray).
However, common astrophysics usage has come to use EMR
terminology for such photons, and reserve the term cosmic ray
for fermions: protons and heavier nuclei.
They are theorized to be formed largely by supernovae.
Some classes of cosmic-ray particles by kinetic energy:
- VHE cosmic rays or VHECR or very-high energy cosmic rays - above 100 GeV.
- UHE cosmic rays or UHECR or ultra-high energy cosmic rays - above 100 TeV.
- EE cosmic rays or EECRs or extreme energy cosmic rays - above 50 million TeV (5 × 1019 eV, the GZK limit).
A famous graph, the Swordy plot demonstrates
that cosmic rays occur basically
n a power law spectrum over a wide range.
Advanced Composition Explorer (ACE)
anomalous cosmic rays (ACR)
cosmic background radiation (CBR)
Lunar Reconnaissance Orbiter (LRO)
Van Allen belts