Answer :
In Geiger–Müller (GM) detectors, a quench gas plays a crucial role. A GM detector is a type of particle detector that measures ionizing radiation. Here’s what a quench gas is and why it is used:
What is a Quench Gas?
- A quench gas is an inert or molecular gas added to the primary gas within a GM tube, which is part of a GM detector. Common quench gases include halogen gases or organic vapors like ethanol.
Why Are Quench Gases Used?
Prevent Afterpulses: When ionizing radiation enters the detector, it creates a cascade of charged particles, causing a discharge. A quench gas absorbs the energy of these charged particles before they can cause additional discharges (called afterpulses), which would lead to inaccurate readings.
Aid in Stabilization: Quench gases help in stabilizing the discharge process so that each particle interaction results in a single discharge event. This ensures that the GM tube returns promptly to a ready state for the next radiation event.
How It Works
- After the primary ionizing event, the quench gas molecules absorb the leftover energy from the charged particles. When these molecules return to their stable state, they do not cause further ionization within the detector, thanks to their specific design characteristics.
In summary, quench gases are critical in ensuring that GM detectors measure radiation accurately by preventing secondary discharges and by stabilizing the detector operation.
