KVPY2019PhysicsNuclear Physics
Originally the radioactive beta decay was thought as a decay of a nucleus with the emission of electrons only (Case I) . However, in addition to the electron, another (nearly) massless and electrically neutral particle is also emitted (Case II). Based on the figure below, which of the following is correct?
Options
- A(a) in both cases I and II
- B(a) in case I and (b) in case II
- C(a) in case II and (b) in case I
- D(b) in both cases I and II
Correct answer
C. (a) in case II and (b) in case I
Step-by-step solution
β - decay occurs as X Z A ⟶ Y Z + 1 A + β - 1 0 + v ¯ Most of the decay energy is carried by both emitted electron β - and antineutrino v ¯ . So, β - - particles emerges with varrying energies and energy spectrum of emitted β - is as shown; If there are no antineutrinos, energy is carried mainly by β - - particles, so energy spectrum will be