At the Heart of the AtomIntroduction |
Are there uses for alpha decay? |
The decay of uranium and thorium produces all the helium that exists on Earth. Most of the helium is mixed with natural gas and is extracted from gas wells. It is expensive to separate and store the helium, but, given the increasing needs for this resource for cooling superconducting magnets used in hospital MRI machines, it is an effort that must be made.
Alpha-emitting radioactive elements are used in smoke detectors. The charged alpha particles leaving the element are collected on a metal plate where they produce a small electric current. Smoke scatters the alphas, reducing the current, and triggering the alarm.