Principle
When photons are scattered on electrons, their momentum and energy gets changed. The energy of scattered gamma-radiation is measured as a function of the angle of scatter. The Compton wavelength is determined from the measured values.
Benefits
- Experience the essence of the Nobel Prize: Compton (1927)
- Nobel Prize experiment can be performed by students within some hours
- Impressive second proof of the wave-particle dualism
- Use of a gamma detector in combination with a high precision power supply guarantees good and reproducible results
Tasks
- Calibrate the measuring set-up with the aid of a Cs-137 calibrating source (37 kBq) and a Na-22 source (74 kBq).
- Measure the energy of the Cs-137 661.6 keV peaks scattered at different angles and calculate the Compton wavelength from the readings taken.
Learning objectives
- Corpuscle
- Scattering
- Compton wavelength
- g-quanta
- de Broglie wavelength
- Klein-Nishina formula