# Deuteron is a bound state of a neutron and

Question:

Deuteron is a bound state of a neutron and a proton with a binding energy B = 2.2 MeV. A γ -ray of energy E is aimed at a deuteron nucleus to try to break it into a

(neutron + proton) such that the n and p move in the direction of the incident γ-ray. If E = B, show that this cannot happen. Hence calculate how much bigger than

B must E be for such a process to happen.

Solution:

The binding energy of a deuteron = B = 2.2 MeV

Kn, Kp are the kinetic energies of neutron and proton

pn and pp are the momentum of neutron and proton

E – B = Kn + Kp

B must be B2/4mc2 for B to be much bigger than E.