beta-minus decay

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beta-minus decay

physics

Also known as: electron emission, negative beta decay, negative beta-particle decay, negatron emission(Show More)

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June 22, 2026

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Beta-minus decay, also known as negative beta decay, is a type of radioactive disintegration where an unstable atomic nucleus releases excess energy by emitting an energetic electron and an antineutrino. In this process, a neutron within the nucleus transforms into a proton, increasing the atomic number of the nucleus by one while keeping the mass number the same. For example, tritium (hydrogen-3) decays into helium-3 through beta-minus decay. The emitted electrons, called beta particles, can have a wide range of energies. This decay is a result of the weak interaction and is a fundamental process in nuclear physics.123

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radioactivity
Beta-minus decay
In beta-minus decay, an energetic negative electron is emitted, producing a daughter nucleus of one higher atomic number and the same mass number. An example is the decay of the uranium daughter product thorium-234 into protactinium-234:
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In beta-minus decay, an energetic negative electron is emitted, producing a daughter nucleus of one higher atomic number and the same mass number. An example is the decay of the uranium daughter product thorium-234 into protactinium-234:
Read More

beta decay
In electron emission, also called negative beta decay (symbolized β⁻-decay), an unstable nucleus emits an energetic electron (of relatively small mass) and an antineutrino (with little or possibly no rest mass), and a neutron in the nucleus becomes a proton that remains in the product nucleus. Thus, negative beta decay…
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In electron emission, also called negative beta decay (symbolized β⁻-decay), an unstable nucleus emits an energetic electron (of relatively small mass) and an antineutrino (with little or possibly no rest mass), and a neutron in the nucleus becomes a proton that remains in the product nucleus. Thus, negative beta decay…
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radiation measurement
Radiation interactions in matter
Another example is the beta-minus radiation also emitted in the decay of some radioactive nuclei. In this case, each nuclear decay produces a fast electron that carries a negative charge of one unit. In contrast, there are other types of ionizing radiation that carry no electrical charge. Common examples…
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Another example is the beta-minus radiation also emitted in the decay of some radioactive nuclei. In this case, each nuclear decay produces a fast electron that carries a negative charge of one unit. In contrast, there are other types of ionizing radiation that carry no electrical charge. Common examples…
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transuranium element
Discovery of the first transuranium elements
The above process is called negative beta-particle decay. A nucleus may also emit a positron, or positive electron, thus changing a proton into a neutron and reducing the positive charge by one (but without changing the mass number); this process is called positive beta-particle decay. In another type of beta…
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The above process is called negative beta-particle decay. A nucleus may also emit a positron, or positive electron, thus changing a proton into a neutron and reducing the positive charge by one (but without changing the mass number); this process is called positive beta-particle decay. In another type of beta…
Read More