Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
active detector
References
Images
detector output connected to a measuring circuit elements of pulse-processing systems
Britannica AI Icon

active detector

physics
Written by
The Information Architects of Encyclopaedia Britannica

The Information Architects maintain a master list of the topics included in the corpus of  Encyclopædia Britannica, and create and manage the relationships between them.
The Information Architects of Encyclopaedia Britannica
Last updated

Quick Summary

detector output connected to a measuring circuit
detector output connected to a measuring circuit Figure 1: (A) A simple equivalent circuit for the development of a voltage pulse at the output of a detector. R represents the resistance and C the capacitance of the circuit; V(t) is the time (t)-dependent voltage produced. (B) A representative current pulse due to the interaction of a single quantum in the detector. The total charge Q is obtained by integrating the area of the current, i(t), over the collection time, tc. (C) The resulting voltage pulse that is developed across the circuit of (A) for the case of a long circuit time constant. The amplitude (Vmax) of the pulse is equal to the charge Q divided by the capacitance C.

Active detectors produce a real-time signal indicating the presence of ionizing radiation. These devices can detect individual radiation quanta, such as alpha particles or X-ray photons, or respond to the collective effect of multiple quanta within their response time.123

Active detectors operate in different modes:
* Pulse mode: Detectors generate a distinct pulse for each detected quantum. This mode allows for counting individual events and can provide timing information, such as the precise arrival time of radiation.13
* Current mode: Detectors produce a continuous current proportional to the rate of radiation interacting with the detector.2
* Integrating mode: The detector's current is accumulated over a period, providing a measure of the total exposure rather than real-time intensity variations.4

Active detectors are crucial for various applications, including radiation measurement and monitoring, where immediate detection and characterization of radiation are necessary.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
4 Britannica Sources
  1. radiation measurement - Counting systems
  2. radiation measurement - Applications of radiation interactions in detectors
  3. radiation measurement - Timing characteristics
  4. radiation measurement - Integrating mode

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.