Principle

An X-ray tube with a tungsten anode generates X-radiation that is selected with the aid of a monocrystal as a function of the Bragg angle. A Geiger-Müller counter tube measures the intensity of the radiation. The glancing angles of the characteristic X-ray lines are then used to determine the energy.

Tasks

1. Record the intensity of the X-rays emitted by the copper anode as a function of the Bragg angle using a LiF monocrystal as analyzer.
2. Calculate the energy values of the characteristic copper lines and compare them with the energy differences of the tungsten energy terms. Assigned them to the corresponding transitions taking into account the quantum-mechanical selection rules.

Learning objectives

• X-ray tube
• Bremsstrahlung
• characteristic radiation
• energy levels
• crystal structures
• lattice constant
• absorption
• absorption edges
• interference
• the Bragg equation
• order of interference