What is the process through which x-rays create charged particles such as free electrons?

What is the process through which x-rays create charged particles such as free electrons?

• A. Pair production
• B. Induction
• C. Annihilation
• D. Ionization

Answer: (D)

X-rays interact with matter by transferring energy to electrons bound in atoms. When an x-ray photon has enough energy to overcome an electron’s binding energy, that electron is ejected from the atom. The result is a free electron and a positively charged ion, which is exactly ionization. In diagnostic x-ray ranges, the two main pathways that cause this are the photoelectric effect and Compton scattering, both of which leave behind free electrons. Pair production would require much higher energies and creates an electron-positron pair, which is not the typical result at diagnostic energies, and annihilation is the process that occurs when a positron meets an electron. Induction isn’t a mechanism for producing free electrons with x-rays. So the process described is ionization.

X-rays interact with matter by transferring energy to electrons bound in atoms. When an x-ray photon has enough energy to overcome an electron’s binding energy, that electron is ejected from the atom. The result is a free electron and a positively charged ion, which is exactly ionization. In diagnostic x-ray ranges, the two main pathways that cause this are the photoelectric effect and Compton scattering, both of which leave behind free electrons. Pair production would require much higher energies and creates an electron-positron pair, which is not the typical result at diagnostic energies, and annihilation is the process that occurs when a positron meets an electron. Induction isn’t a mechanism for producing free electrons with x-rays. So the process described is ionization.