Answer :
Final answer:
A gas-filled detector's anode is a positively charged electrode that collects free electrons produced by ionization within the detector's gas volume when exposed to ionizing radiation.
Explanation:
The anode in a gas-filled detector, such as a Geiger-Müller tube or other types of gaseous ionization detectors, is a positively charged electrode; it attracts the free electrons produced by ionization within the gas. When ionizing radiation enters the detector, it interacts with the gas molecules, leading to ionization and the production of charged particles (electrons and positive ions). The electrons are attracted to the anode, resulting in a measurable current. One common type includes sensors filled with gases like helium-3 (³He) or Boron trifluoride (BF3), employed in neutron detection. However, the performance of these detectors can be limited by the difficulty in achieving a precise and consistent gas thickness, unlike solid-state detectors, such as scintillators, where precise thickness control enhances detection efficiency.
