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Gamma rays
Intermediate
Highest-energy photons from nuclear processes.
The highest-energy EM radiation (>100 keV), from nuclear transitions and cosmic events. Penetrating and ionising, used in cancer therapy and sterilisation.
Cobalt-60 emits 1.17 and 1.33 MeV.
Shielded by lead and thick concrete.
In more detail
Gamma rays have the shortest wavelengths and highest energies in the electromagnetic spectrum, and they are emitted by nuclear decay and cosmic events. They are very penetrating and ionising.
Real-world uses
- Radiotherapy uses gamma rays to treat tumours.
- Astronomers study gamma-ray bursts from distant galaxies.
- Astronomers study gamma rays from distant explosions and nuclear processes to learn about the most energetic events.
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Frequently asked questions
Where do gamma rays come from?
Nuclear transitions, radioactive decays and high-energy astrophysical processes.
What shields gamma rays?
Dense materials such as lead or thick concrete.
Are gamma rays only from space?
No. They are also produced in radioactive decay and in medical treatments, which must be carefully shielded.
Related topics in AC Circuits & EM Waves
Visible light · Ultraviolet · X-rays · Polarisation of EM waves · Antennas · Waveguides and transmission lines