What is meant by scintillator?
A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate (i.e. re-emit the absorbed energy in the form of light).
What does a scintillator do?
Scintillators are materials that are able to convert high energy radiation such as X or gamma-rays to a near visible or visible light. They are widely used as detectors in medical diagnostics, high energy physics and geophysical exploration (ref. Knoll).
What is chemical quenching?
Chemical quenching means that a reactant is introduced to favor an endothermic reaction with an associated reduction of temperature. Also, the lowered temperature of the introduced reactant strengthens the effect.
How does a scintillator detector work?
Scintillation detectors are usually water clear crystalline materials and work better if they contain heavy elements, which are more likely to intercept a gamma ray within the material and absorb its energy. After absorbing a gamma ray, a scintillation crystal emits a pulse of light, usually in the visible spectrum.
What does the scintillator measure?
A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses.
What is quenching in radioactivity?
Quenching is defined as the irreversible absorption of decay energy or photons during the energy transfer from the decaying particle to the photocathode. Chemical quenching prevents the energy transfer from decay particle to the scintillator. It is in practice the most frequent kind of quenching.
How does a Dynode work?
A dynode is an electrode in a vacuum tube that serves as an electron multiplier through secondary emission. Secondary emission occurs at the surface of each dynode. Such an arrangement is able to amplify the tiny current emitted by the photocathode, typically by a factor of one million.
Why quenching is done?
A type of heat treating, quenching prevents undesired low-temperature processes, such as phase transformations, from occurring. Even cooling such alloys slowly in air has most of the desired effects of quenching; high-speed steel weakens much less from heat cycling due to high-speed cutting.
What is the main function of a detection system formed by a scintillator crystal that is coupled with a photomultiplier tube?
Scintillation detectors are used in conjunction with a photomultiplier tube to convert the scintillation light pulse into an electric pulse.
What is quenching in GM counter?
Quenching – Dead Time – Geiger Counters In a Geiger counter the fill gas of the chamber is an inert gas which is ionized by incident radiation, and a quench gas of 5–10% of an organic vapor or a halogen gas to prevent spurious pulsing by quenching the electron avalanches.
When does a chemical quench occur in a solvent?
Chemical Quench occurs when the energy of the beta particle is absorbed by compounds that will not (or with too low efficiency) re-emit the energy during the transfer to the solvent molecules. The energy of the beta particle will not reach the scintillator and consequently, no light will reach the detector.
What kind of applications can scintillators be used for?
Scintillators can also be used in particle detectors, new energy resource exploration, X-ray security, nuclear cameras, computed tomography and gas exploration. Other applications of scintillators include CT scanners and gamma cameras in medical diagnostics, and screens in older style CRT computer monitors and television sets.
How is scintillator related to the property of luminescence?
Scintillator. A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate (i.e. re-emit the absorbed energy in the form of light).
When is a scintillator excited by ionizing radiation?
A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation.
