Beta Decay

“ Beta Decay is a radioactive disintegration in which unstable atomic nuclei spontaneously dissipate excess energy and undergo a change of one unit of positive charge without any change in mass number. The processes involved in Beta Decay are electron emission, positron emission, and electron capture”.

Types of Beta Decay

• Beta-positive decay or β ⁺
• Beta-negative decay or β ^-

Beta-positive Decay or β ⁺

• In a Beta-positive Decay orβ ⁺ , a proton is transformed into a neutron with a decrease in the atomic number of the radioactive element. Hence, there is a loss of proton and a gain of neutron inside the nucleus.
• The Beta-positive Decay process also produces a positron and a neutrino to maintain the law of conservation of charge.
• Positron is similar to electrons in all aspects but charges are different, positron is of positive charge and electron of negative charge.
• The behavior of a neutrino is similar to that of an antineutrino.

p = n + e ⁺ + ν

X _Z ^A → Y _Z-1 ^A + e ⁺ + ν

Beta-negative Decay or β ^-

• In a Beta-negative Decay orβ ^- , the neutron is transformed into a proton with an increase in the atomic number of the radioactive element. Where the proton is a positive charge and neutrons are neutral.
• In a Beta-negative Decay orβ ^- , the nucleus also produces an electron and an antineutrino to maintain the conservation of charge.
• The antimatter counterpart of neutrinos is known as antineutrino. They are neutral particles with negligible mass, so the interaction of these particles with other matter is so weak that the entire earth remains without being disturbed.

Electron Capture

p + e ^- → n + ν

C ₆ ¹¹ + e ^- → B ₅ ¹¹ + ν

Fermi Theory of Beta Decay

Application of Beta Decay

Gamma Decay

Co ₂₇ ⁶⁰ Ni ₂₈ ⁶⁰ + e ^- + ν + γ + 1.17 MeV

Ni ^* ₂₈ ⁶⁰ → Ni ₂₈ ⁶⁰ + γ + 1.33 MeV

Sources of Gamma Rays

Application of Gamma Rays

• Gamma-ray sensors are also used in the food packaging and chemical industry to measure density, thickness, and composition.
• Gamma rays are used to treat certain types of cancer where the high energy gamma beams are irradiated on the cancerous cells to kill them.
• Fermi Gamma-ray Space Telescope that provides an unparalleled view of the universe.