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प्रश्न
What is beta decay?
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उत्तर
The nucleus emits an electron produced by converting a neutron in the nucleus into a proton. During beta decay, the number of nucleons i.e., the mass number of the nucleus remains unchanged. The daughter nucleus has one less neutron and one extra proton.
There is another type of beta decay called the beta plus decay in which a proton gets converted to a neutron by emitting a positron and a neutrino. A positron is a particle with the same properties as an electron except that its charge is positive. It is known as the antiparticle of electron.
In beta decay also, the total mass of the products of the decay is less than the mass of the parent atom. The excess mass is converted into kinetic energy of the products. The Q value for the decay can be written as
Q = [mX - mY - me]c2
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