Final answer:
The anode heel effect refers to the variation in photon distribution between the anode and cathode ends of the x-ray tube. X-rays are produced in the anode through two processes: bremsstrahlung radiation and characteristic x-rays. Bremsstrahlung radiation is the result of electron deceleration in the anode material, while characteristic x-rays come from atomic excitations unique to the anode material.
Step-by-step explanation:
The variation in photon distribution between the anode and cathode ends of the x-ray tube is known as the anode heel effect. In an x-ray tube, there are two processes by which x-rays are produced: bremsstrahlung radiation and characteristic x-rays. Bremsstrahlung radiation occurs when electrons are decelerated in the anode material, resulting in a smooth distribution of x-ray photons. Characteristic x-rays, on the other hand, come from atomic excitations specific to the anode material, resulting in sharp peaks in the x-ray spectrum. These features are explored further in the field of Atomic Physics.