Principle

The inverse square law of distance is demonstrated with the
gamma radiation from a 60-Co preparation, the half-value thickness
and absorption coefficient of various materials determined with the
narrow beam system and the corresponding mass attenuation
coefficient calculated.

Tasks


To measure the impulse counting rate as a function of the
distance between the source and the counter tube.

To determine the half-value thickness d1/2 and the absorption
coefficient of a number of materials by measuring the impulse
counting rate as a function of the thickness of the irradiated
material. Lead, iron, aluminium, concrete and Plexiglas are used as
absorbers.

To calculate the mass attenuation coefficient from the measured
values.


What you can learn about


Radioactive radiation

β-decay

Conservation of parity

Antineutrino



g-
quants



Half-value
thickness


Absorption coefficient

Term diagram

Pair formation

Compton effect

Photoelectric effect

Conservation of angular momentum

Forbidden transition

Weak interaction

Dead time