# Before the neutrino hypothesis,

Question:

Before the neutrino hypothesis, the beta decay process was thought to be the transition, nP+e¯">n→P+e¯ If this was true, show that if the neutron was at rest, the proton and electron would emerge with fixed energies and calculate them. Experimentally, the electron energy was found to have a large range.

Solution:

Let us consider cases before and after β-decay

Before β-decay, En = mnc2 and pn = 0

After β-decay, pn = pp + pe

pc = mnc2 – mpc2 = 938 MeV – 936 MeV = 2 MeV

Ep = 936 MeV

Ee = 2.06 MeV