Excitation of kl m and n shells and Formation of Ka to Ma Characteristic X-rays If an incoming electron has sufficient kinetic energy for knocking out an electron of the K shell (the inner-most shell), it may excite the atom to an K high-energy state(k state) One of the outer electron falls subshells into the K-shell vacancy emitting the excess energy as Energ Kstate (shell a X-ray photon Characteristic X-ray energy L state x-ray Et final-cinitial K excitation中 M state EK>EL>EM excitation EKB>EKa N state ground state2/9/2021 ▪ If an incoming electron has sufficient kinetic energy for knocking out an electron of the K shell (the inner-most shell), it may excite the atom to an high-energy state (K state). ▪ One of the outer electron falls into the K-shell vacancy, emitting the excess energy as a x-ray photon. ▪ Characteristic x-ray energy: Ex-ray=Efinal-Einitial Excitation of K, L, M and N shells and Formation of K to M Characteristic X-rays K L M N K K L Energy K state (shell) L state M state N state ground state K K L L K1 K2 I II III M subshells EK>EL>EM EK>EK K excitation L excitation M