“scintillation counter”的概念、定义、翻译、参考文献-科学参考

scintillation counter

Physics

A type of particle or radiation counter that makes use of the flash of light (scintillation) emitted by an excited atom falling back to its ground state after having been excited by a passing photon or particle. The scintillating medium is usually either solid or liquid and is used in connection with a photomultiplier, which produces a pulse of current for each scintillation. The pulses are counted with a scaler. In certain cases, a pulse-height analyser can be used to give an energy spectrum of the incident radiation.

Astronomy

A device for detecting high-energy X-rays and gamma rays. It makes use of the effect of scintillation, in which the incident radiation is converted into a flash of light by interaction with a sensitive material such as caesium iodide or sodium iodide (CsI or NaI). The intensity of the flash is proportional to the energy of the radiation, and it can be converted into an electronic signal by a photomultiplier tube or, in an imaging telescope, by a microchannel plate detector or charge-coupled device (CCD).

Space Exploration

An instrument for measuring very low levels of radiation. The radiation strikes a scintillator (a device that emits a unit of light when a charged elementary particle collides with it), whose light output is ‘amplified’ by a photomultiplier; the current pulses of its output are in turn counted or added by a scaler to give a numerical reading.

Electronics and Electrical Engineering

A radiation counter that consists of a scintillator (see scintillation), photomultiplier, amplifier, and scaler and is used to measure the activity of a radioactive source. The scintillator crystal emits flashes of light of a characteristic frequency when exposed to gamma rays from a radioactive source. Each scintillation produces an output pulse from the photomultiplier. The count rate produced from the photomultiplier is measured and the activity of the source calculated.
The scintillation counter is energy-dependent since the frequency of the emitted light in dependent on the energy of the incident radiation. The energy of the electrons emitted from the photocathode is a function of the light frequency and hence pulses produced by radiation of energy other than that being considered may be excluded using a suitable discriminator circuit. The signal-to-noise ratio is therefore improved relative to other radiation counters, such as the Geiger counter, since background radiation and scattered radiation may be excluded, and one radioactive nuclide may be counted in the presence of another.
The energy dependence of a scintillation counter may also be used to study the energy distribution of radioactive nuclides, thus using it as a scintillation spectrometer.

Biology

A type of particle or radiation counter that makes use of the flash of light (scintillation) emitted by an excited atom falling back to its ground state after having been excited by a passing photon or particle. The scintillating medium is usually either solid or liquid and is used in connection with a photomultiplier, which produces a pulse of current for each scintillation. The pulses are counted to enable the radioactivity of the source to be calculated. The distribution of a radiolabelled compound, such as a drug, in an organism can be determined in this way by testing tissue samples from different organs after drug administration.

Geology and Earth Sciences

An instrument which measures gamma radiation and is extensively used in airborne and ground radiometric surveys. It utilizes the flash of light emitted when the atoms of a suitable ‘phosphor’ (e.g. a large sodium iodide crystal ‘doped’ with thallium) are energized by gamma rays. The scintillations are detected by the light-sensitive cathode of a photomultiplier tube and are converted by the succession of electrodes in the tube into a stream of electrons which are collected and recorded on a meter. The scintillation counter has now been developed into the gamma-ray spectrometer (see gamma-ray spectrometry) for portable and airborne use. It analyses the complex gamma-ray spectrum of uranium, thorium, and potassium, and indicates the relative gamma-ray contribution of each element to ground gamma-ray emission on a continuous readout.

单词	scintillation counter
释义	scintillation counter Physics A type of particle or radiation counter that makes use of the flash of light (scintillation) emitted by an excited atom falling back to its ground state after having been excited by a passing photon or particle. The scintillating medium is usually either solid or liquid and is used in connection with a photomultiplier, which produces a pulse of current for each scintillation. The pulses are counted with a scaler. In certain cases, a pulse-height analyser can be used to give an energy spectrum of the incident radiation. Astronomy A device for detecting high-energy X-rays and gamma rays. It makes use of the effect of scintillation, in which the incident radiation is converted into a flash of light by interaction with a sensitive material such as caesium iodide or sodium iodide (CsI or NaI). The intensity of the flash is proportional to the energy of the radiation, and it can be converted into an electronic signal by a photomultiplier tube or, in an imaging telescope, by a microchannel plate detector or charge-coupled device (CCD). Space Exploration An instrument for measuring very low levels of radiation. The radiation strikes a scintillator (a device that emits a unit of light when a charged elementary particle collides with it), whose light output is ‘amplified’ by a photomultiplier; the current pulses of its output are in turn counted or added by a scaler to give a numerical reading. Electronics and Electrical Engineering A radiation counter that consists of a scintillator (see scintillation), photomultiplier, amplifier, and scaler and is used to measure the activity of a radioactive source. The scintillator crystal emits flashes of light of a characteristic frequency when exposed to gamma rays from a radioactive source. Each scintillation produces an output pulse from the photomultiplier. The count rate produced from the photomultiplier is measured and the activity of the source calculated. The scintillation counter is energy-dependent since the frequency of the emitted light in dependent on the energy of the incident radiation. The energy of the electrons emitted from the photocathode is a function of the light frequency and hence pulses produced by radiation of energy other than that being considered may be excluded using a suitable discriminator circuit. The signal-to-noise ratio is therefore improved relative to other radiation counters, such as the Geiger counter, since background radiation and scattered radiation may be excluded, and one radioactive nuclide may be counted in the presence of another. The energy dependence of a scintillation counter may also be used to study the energy distribution of radioactive nuclides, thus using it as a scintillation spectrometer. Biology A type of particle or radiation counter that makes use of the flash of light (scintillation) emitted by an excited atom falling back to its ground state after having been excited by a passing photon or particle. The scintillating medium is usually either solid or liquid and is used in connection with a photomultiplier, which produces a pulse of current for each scintillation. The pulses are counted to enable the radioactivity of the source to be calculated. The distribution of a radiolabelled compound, such as a drug, in an organism can be determined in this way by testing tissue samples from different organs after drug administration. Geology and Earth Sciences An instrument which measures gamma radiation and is extensively used in airborne and ground radiometric surveys. It utilizes the flash of light emitted when the atoms of a suitable ‘phosphor’ (e.g. a large sodium iodide crystal ‘doped’ with thallium) are energized by gamma rays. The scintillations are detected by the light-sensitive cathode of a photomultiplier tube and are converted by the succession of electrodes in the tube into a stream of electrons which are collected and recorded on a meter. The scintillation counter has now been developed into the gamma-ray spectrometer (see gamma-ray spectrometry) for portable and airborne use. It analyses the complex gamma-ray spectrum of uranium, thorium, and potassium, and indicates the relative gamma-ray contribution of each element to ground gamma-ray emission on a continuous readout.
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