How can you make invisible radiation visible




Radiation energy can be converted to other forms of energy, e.g. light. In this movie, we expose quartz tubes to an extremely high radiation dose of 250 sievert, comparable to 100,000 years of background radiation at once.  Part of the radiation energy is stored in the atomic structure of the glas when the tubes are irradiated after they are cooled down to -196˚C (= -321˚F). The stored energy is released as blue light the moment the tube is heated to room temperature by blowing hot air through it. You can see the tube glow in the dark for a short moment.


To measure the radiation dose of radiation workers, they wear a so-called personal dose meter. The same effect as in this movie is used in these meters, only a different material is used. The detector material can store radiation energy at room temperature and it is released only after heating the material up to 200˚C (= 400 ˚F). The light intensity is then measured and corresponds to the radiation dose received by the worker.


The quartz tubes do not become radioactive during irradiation. They are very cold though! When picking them out of the beaker with liquid nitrogen, we have to be very careful.