Author Question: The disintegration energy for gamma decay of a nucleus is typically on the order of 10-100 keV and ... (Read 51 times)

oliviahorn72 · **on:** Jul 28, 2018

The disintegration energy for gamma decay of a nucleus is typically on the order of 10-100 keV and can even be on the order of MeV. Which of the following statements best describes why the energies are so much larger than from atoms?
a. Energy levels within the nucleus are spaced farther apart than atomic levels.
b. The spins of the paired protons and neutrons within the nucleus are aligned within energy levels.
c. The higher energies of the gamma rays are higher in probability of emission because they must tunnel through classically forbidden regions.
d. All nuclei are only metastable, increasing binding energy exponentially when the nucleus is in an excited state.
e. The Coulomb attraction within the nucleus places it lower in energy, therefore greater excitation energies are necessary.

Question 2

Alpha decay occurs in some radioactive nuclides with A > 150. The probability of an alpha particle being emitted depends on the energy of the alpha particle. Why is this so?

s.meritte · **Reply #1 on:** Jul 28, 2018

Answer to Question 1

Energy levels within the nucleus are spaced farther apart because of the stronger nuclear reactions. Atoms experience excited states as well when they absorb a photon, but the Coulomb interaction is far less potent than the strong nuclear reaction. This is why gamma rays that excite nuclear energy levels are so much greater.
a.

Answer to Question 2

b.
Many of the alpha particles emitted in nuclear decay do not have the classically defined energy to surmount the potential barrier of the strong nuclear force. Higher energy particles, however, do have higher probabilities of getting out due to the decreasing potential over distances. They have less of the classically forbidden region to pass through.