A free proton cannot decay into (n+e^(+)+v), because such decay is not energetically allowed. Yet we observe in nature beta decay with positron emission. How do we understand the emission of positrons form nuclei?

A free proton cannot decay into (n+e^(+)+v), because such decay is not

1.	A free proton cannot decay into (n+e^(+)+v), because such decay is not energetically allowed. Yet we observe in nature beta decay with positron emission. How do we understand the emission of positrons form nuclei?
Answer» Solution :A FREE proton cannot decay into a neutron as the Q value of reaction becomes negative. However, inside the nucleus, both protons and neutrons are BOUND. The bound NUCLEONS behave differently than free nucleons. When we take into account the energetic of parent and DAUGTHER nuclie involved in beta PLUS decay (or positron decay), the decay is always energetically allowed.

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A free proton cannot decay into (n+e^(+)+v), because such decay is not energetically allowed. Yet we observe in nature beta decay with positron emission. How do we understand the emission of positrons form nuclei?

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