Some chemical elements have isotopes which emit radiation and as a result change into a different element. This process is know as radioactive decay or radioactivity and these isotopes are called radioisotopes. Background radiation comes from a variety of sources, such as the following 1a . Measuring It is recommended that the background radiation be measured before any set of experiments, even on the same day, since it can vary considerably. Detectors Different radiation gets detected by different types of detectors.
Most detectors simply indicate the arrival of energy.
2 Ionization Chamber Detects alpha, beta. Produces ionization These are not very sensitive and work by charging two electrodes, one strongly positive the other strongly negative. By placing a galvonometer across the electrodes the ionisations can be detected as pulses of current. Low energy gammas are also detected, but poorly. Cloud and Similar Chambers Detects Alpha, Beta, Gamma Produces ionization A charged particle travelling at speed leaves behind a trail of ions.