Matter is composed of combinations of **subatomic** or **fundemental particles** made up of
**quarks** bound together by **glouns**.

Electrons typically have a negative charge (negaton) but may also have a positive charge (positron). The charge of an electron
is \(e = -1.60219 \cdot 10^{-19} \; [C]\).
The process of **electron annihilation** occurs when a positron collides with a negatron releasing two of more
photons known as **annihilation radiation**.

Protons have a positive charge equal and opposite to an electron.

Neutrons are electrically neutral and have a mass similar to a proton. Neutrons are not stable on their own; only when bounded within a nucleus. A free neutron decays into a proton with the emission of a negative electron and an antineutrino ( \( \beta \) decay) in a process that takes about 12 minutes.

Photons are the particle associated with electromagnectic waves. Photons have no charge or mass and travel in vacuum at the speed of light ( \( c = 2.9979 \cdot 10^8 \; [m/s]\) )

Neutrinos are another particle with no charge or mass. Those common to nuclear engineering are electron neutrinos and electron antineutrinos.

Element | Mass \( \; [kg] \) | Charge \( \; [C] \) |

Electron | \(9.10954 \cdot 10^{-31}\) | \(-1.60219 \cdot 10^{-19}\) |

Proton | \(1.67265 \cdot 10^{-27}\) | \(1.60219 \cdot 10^{-19}\) |

Neutron | \(1.67495 \cdot 10^{-27}\) | \(-\) |

Photon | \(-\) | \(-\) |

Neutrinos | \(-\) | \(-\) |