Does the "K-shell" Another Way of Making X-rays?

Atoms have their electrons arranged in closed "shells" of different energies. Well, the K-shell is the lowest energy state of an atom. It can give it enough energy to knock it out of its energy state. Then a tungsten electron of higher energy (from an outer shell) can fall into the K-shell.

The energy lost by the falling electron shows up in an emitted x-ray photon. Meanwhile, higher energy electrons fall into the vacated energy state in the outer shell, and so on. K-shell emission produces higher-intensity x-rays than Bremsstrahlung, and the x-ray photon comes out at a single wavelength.

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