A beta particle is a high-energy electron that is emitted from the nucleus of an atom during radioactive decay. When a beta particle is emitted, a neutron in the nucleus is converted into a proton and an electron. The electron is emitted from the nucleus, while the proton remains in the nucleus.
The conversion of a neutron into a proton increases the number of protons in the nucleus by one, while the emission of an electron decreases the number of electrons in the atom by one. This results in an increase in the atomic number of the isotope by one, while the mass number remains the same.
