Alpha particles comprise 2 neutrons and 2 protons. Because of their large mass and relatively slow speed, alpha particles are the least penetrating of the three types of radiation, and can be stopped by a sheet of paper. Beta particles are electrons that can travel farther than alpha particles, but not as far as high-energy gamma photons, the third type of radiation.
The scintillators were then coupled to a photomultiplier tube, a device that converts the light pulses into electrical current. Because the shape of a light pulse differs depending on which type of radiation produced it (alpha particles produce sharp peaks, gamma particles more broad pulses), the device could distinguish between the different radiation types and produce counts for all three simultaneously. The new device could be used for a range of applications in which scientists might need to determine the types of radioactive material present, the researchers write.
Contacts and sources:
American Institute of Physics
Article: "Development of an alpha/beta/gamma detector for radiation monitoring" is accepted for publication in Review of Scientific Instruments.
Authors: Seiichi Yamamoto (1) and Jun Hatazawa (2).
(1) Kobe City College of Technology, Kobe, Japan
(2) Osaka University Graduate School of Medicine, Osaka, Japa