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Question
Write the basic nuclear process underlying β+ and β– decays.
Solution
Basic process underlying β+ and β− decay are
During a weak interaction an atomic nucleus converts into a nucleus with one higher atomic number while emitting one electron and an electron antineutrino this is called beta minus decay.
`X_Z^A->Y_(Z+1)^A+e^(-)+ bar(v_e)`
During a weak interaction an atomic nucleus converts into a nucleus with one lower number while emitting a positron and electron neutrino this is called beta Plus decay.
`X_Z^A->Y_(Z-1)^A+e^(+)+v_e`
RELATED QUESTIONS
For the `beta^+` (positron) emission from a nucleus, there is another competing process known as electron capture (electron from an inner orbit, say, the K−shell, is captured by the nucleus and a neutrino is emitted).
\[\ce{e+ + ^A_Z X -> ^A_{Z - 1}Y + \text{v}}\]
Show that if `beta^+` emission is energetically allowed, electron capture is necessarily allowed but not vice−versa.
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\[\ce{^2_1H + ^3_1H -> ^4_2He}\]
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