6.30 Consider the decay of a free neutron at rest : n p + e .Show that the two-body decay of this type must necessarily give an electron of fixed energy and, therefore, cannot account for the observed continuous energy distribution in the -decay of a neutron or a nucleus (Fig. 6.19).

6.30 Consider the decay of a free neutron at rest : n p + e .Show that the two-body decay of this type must necessarily give an electron of fixed energy and, therefore, cannot account for the observed continuous energy distribution in the -decay of a neutron or a nucleus (Fig. 6.19).
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1 Answer
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6.30 The decay process of free neutron at rest is given as:
n
From Einstein's mass-energy relation, we have the energy of electron as? where,
? m = Mass defect = Mass of neutron – ( Mass of proton + mass of electron)
c = speed of light
? m and c are constant. Hence, the given two-body decay is unable to explain the continuous energy distribution in the -decay of a neutron or a nucleus. The presence of neutrino von the LHS of the decay correctly explain the continuous energy distribution.
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