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Nuclear decay

Nuclear decay
Nuclear decay

Nuclear decay is a stochastic process in which the atomic nucleus spontaneously loses energy and changes composition. The time in which half of the nuclei decay is called the half-life.

In the figure, this is shown for four groups, each with 4 (left) or 400 (right) nuclei. In the counter at the top, the time runs from 0 to 4 half-lives. At the end of the simulation period, there is an average of about 1/16 of the initial number of nuclei left.

The most common decay modes are:

  1. α-decay: the nucleus emits a helium nucleus
  2. β-decay: the nucleus emits a positively or negatively charged electron, or the nucleus captures an orbital electron
  3. γ-decay or internal conversion: the nucleus emits a γ-photon, or the decay energy is transferred to an orbital electron
  4. nuclear fission: the nucleus breaks asymmetrically into two parts with a mass ratio of about 2: 3

Related quantities

Last modified:15 January 2021 11.10 p.m.
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