Gaseous ionization detectors

Gaseous ionization detectors

In particle physics, gaseous ionization detectors are detectors designed to seek the presence of particles (a particle detector). If a particle has enough energy to ionize a gas, the resulting electrons emitted can cause a current flow which can be measured in different ways. Examples are ionization chambers, proportional counters and Geiger-Müller tubes, all of which have the same basic design of two electrodes separated by air or a special counting gas. The strength of the electric field between the electrodes determines the detector's response to ionizing radiation.

Smoke detectors work on this principle; a bit of radioactive americium is placed so that it maintains a current between the two plates. If smoke gets in between the plates where the ionization is taking place, the ionized gas can be neutralized leading to a reduced current. The decrease in current triggers a fire alarm.

Geiger-Müller tubes are the primary components of Geiger counters; as the gas ionizes a current is able to pass through a potential difference between two plates. The peak in current is passed through an audio device producing the clicks of the Geiger counter.

Proportional counters work on a similar principle, but by using a smaller potential difference between the electrodes, the determination of ionization energy is allowed for.

Wire chambers are essentially gaseous ionization detectors with many electrodes instead of one.

Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • Ionization chamber — An ionization chamber is a device used for two major purposes: detecting particles in air (as in a smoke detector), and for detection or measurement of ionizing radiation. An ionization chamber is an instrument constructed to measure the number… …   Wikipedia

  • Flame ionization detector — A flame ionization detector (FID) is a type of gas detector used in gas chromatography. The first flame ionization detector was developed in 1957 by scientists working for the CSIRO in Melbourne, Australia.… …   Wikipedia

  • Neutron detection — is the effective detection of neutrons entering a well positioned detector. There are two key aspects to effective neutron detection: hardware and software. Detection hardware refers to the kind of neutron detector used (the most common today is… …   Wikipedia

  • Particle detector — In experimental and applied particle physics and nuclear engineering, a particle detector, also known as a radiation detector, is a device used to detect, track, and/or identify high energy particles, such as those produced by nuclear decay,… …   Wikipedia

  • Gas Electron Multiplier — The Gas Electron Multiplier (GEM) is a type of gaseous ionization detector used in nuclear and particle physics and radiation detection. All gaseous ionization detectors are able to collect the electrons released by ionizing radiation, guiding… …   Wikipedia

  • Proportional counter — A proportional counter is a measurement device to count particles of ionizing radiation and measure their energy.A proportional counter is a type of Gaseous ionization detector it works on the same principle as the Geiger Müller counter, but uses …   Wikipedia

  • Semiconductor detector — A semiconductor detector is a device that uses a semiconductor (usually silicon or germanium) to detect traversing charged particles or the absorption of photons. In the field of particle physics, these detectors are usually known as silicon… …   Wikipedia

  • Geiger counter — Infobox Laboratory equipment name = Geiger counter caption = A modern geiger counter acronym = other names = Geiger Müller counter uses = Particle detector inventor = Hans Geiger manufacturer = model = related = Geiger Müller tubeA Geiger counter …   Wikipedia

  • Survey meter — Survey meters are portable radiation detection and measurement instruments used to check personnel, equipment, and facilities for radioactive contamination, or check external or ambient ionizing radiation fields (to evaluate the direct exposure… …   Wikipedia

  • Environmental scanning electron microscope — Wool fibers imaged in an ESEM by the use of two symmetrical plastic scintillating backscattered electron detectors …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”