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[edit] Gamma Radiation

• Are forms of electromagnetic radiation (EMR) or light emissions of a specific frequency produced from sub-atomic particle interaction, such as electron-positron annihilation and radioactive decay; most are generated from nuclear reactions occurring within the interstellar medium of space.[1]

In simpler terms, Gamma Rays are electromagnetic waves that accompany alpha or beta decay. They arise from the fall of a nucleus   
from an exited state to a more stable state, similar to the emission lines of chemical elements caused by electrons moving from one  
quantized energy level to another. Gamma Rays are not charged, so they cannot ionize an atom directly through electrical  
interactions. However, they produce electrons indirectly through other interactions with matter

An Example would be several centimeters of lead, or meters of concrete.

• Gamma Rays are the strongest and most powerful type of radiation and will will go right through your hand and deep into a concrete block, this needs shielding.
• These are also purely electron magnetic
• For instance, if you have radioactive source and poke hole in it and put in a magnetic field, gamma will go straight through.