Radioactivity

2. The central part of an atom containing protons and neutrons.
5. Low-level radiation present in the environment from various sources.
7. An application of gamma radiation that cleans medical equipment.
11. A type of particle released in some radioactive decays, made up of two protons and two neutrons.
13. The basic building block of matter, consisting of a nucleus with protons and neutrons, and electrons orbiting the nucleus.
14. Defined as the number of nuclear disintegrations (decays) per second.
15. A neutral particle found in the nucleus of an atom.

1. The addition or removal of an electron from a neutral atom to create an ion.
3. A fictional character who, in comics and movies, gains superpowers after exposure to gamma radiation.
4. People who work with radiation sources wear one of these to measure the amount of radiation they are exposed to.
6. Defined as the time taken for the activity of a radioactive source to half in value.
8. A negatively charged particle moving around the nucleus of an atom.
9. A positively charged particle found in the nucleus of an atom.
10. High-energy electromagnetic waves released during some radioactive decays.
12. An electron emitted from the nucleus of an atom during some radioactive decays.