secondary emission coefficient
Quick Summary
Secondary emission is the ejection of electrons from a solid surface when it's bombarded by charged particles like electrons or ions. This occurs when the bombarding particles transfer kinetic energy to electrons within the material, giving them enough energy to escape the surface.1
The ratio of ejected electrons to bombarding electrons is called the secondary emission coefficient. This effect is crucial in devices like photomultiplier tubes, which amplify weak electric currents, and in image intensifiers that brighten faint images. Secondary emission can also happen in insulators, and coating metal electrodes with thin insulator layers can increase the yield of ejected electrons.21
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- electricitySecondary electron emission
…electrons is known as the secondary emission coefficient. For low-incident energies (below about one electron volt), the primary electrons tend to be reflected and the secondary emission coefficient is near unity. With increasing energy, the coefficient at first falls and then at about 10 electron volts begins to rise again,…
Read More…electrons is known as the secondary emission coefficient. For low-incident energies (below about one electron volt), the primary electrons tend to be reflected and the secondary emission coefficient is near unity. With increasing energy, the coefficient at first falls and then at about 10 electron volts begins to rise again,…
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electron tubeSecondary emissionThe amount of secondary emission depends on the properties of the material and the energy and angle of incidence of the primary electrons. Material properties are characterized by the secondary-emission ratio, defined as the number of secondary electrons emitted per primary electron. Typically, the maximum secondary-emission ratio lies…
Read MoreThe amount of secondary emission depends on the properties of the material and the energy and angle of incidence of the primary electrons. Material properties are characterized by the secondary-emission ratio, defined as the number of secondary electrons emitted per primary electron. Typically, the maximum secondary-emission ratio lies…
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