Nuclei and Radioactivity

Gives the approximate radius of a nucleus of mass number A, where R_0 \approx 1.2\text{ fm}.

Calculates the mass defect and the binding energy holding nucleons together inside a nucleus.

Gives the net energy released or absorbed in a nuclear disintegration or reaction.

Represents spontaneous alpha emission where the parent loses 4 mass units and 2 atomic units.

Gives the fraction of total disintegration energy Q carried away by the alpha particle from a stationary parent nucleus.

Represents nuclear beta-minus emission converting a neutron into a proton, electron, and antineutrino.

Represents positron emission converting a proton into a neutron, positron, and neutrino.

Relates the instantaneous disintegration rate or activity to the number of radioactive nuclei present.

Gives the remaining undecayed nuclei and instantaneous activity after time t.

Relates the half-life period of a radioactive substance to its disintegration constant.

Gives the average lifetime of a radioactive nucleus before disintegration.

Calculates the undecayed population or activity remaining after n elapsed half-life periods.

Gives the overall decay constant and effective half-life for simultaneous independent decay branches.