Electron-volts Electron-volts Electron-withdrawing group electronarcosis electronarcosis electronegative electronegative electronegative electronegative element electronegative element electronegative element electronegative potential electronegatively electronegatively
free electron - electron that is not attached to an atom or ion or molecule but is free to move under the influence of an electric field lepton - an elementary particle that participates in weak interactions; has a baryon number of 0 photoelectron - an electron that is emitted from an atom...
The energy to form an e–h pair,Eeh, is the energy required to excite an electron from thevalence bandinto theconduction band. This energy is generally severalelectron voltsand is roughly proportional to the bandgap energy,Eg. The generation rate of e–h pairs is thus proportional to the en...
came to be used in all applications at low power and low frequency. The commonconceptionat first was that solid-statetechnologywould rapidly render the electron tube obsolete. Such has not been the case, however, for each technology has come to dominate a particular frequency and power range. ...
function.Barium,strontium, andthoriumare commonly used for cathodes because of their low electronic work functions, from 1.2 to 3.5electron volts(eV). Newer experimental materials, such as scandate (analloyof barium andscandiumoxide), have been discovered with slightly lower electronic work functions...
1 by the straight line leading from the atom to infinity; the energy needed for doing this against the attraction of the nucleus is what is called the ionization potential (I), which is usually measured in electron volts (eV). Sign in to download full-size image FIG. 1. A hydrogen ...
In the process, the accelerating field is altered--'self-loaded'--so that about a billion positrons gain five gigaelectronvolts of energy with a narrow energy spread over a distance of just 1.3 metres. They extract about 30 per cent of the wake's energy and form a spectrally distinct ...
It is shown that the electron-cyclotron maser instabilities may readily be excited in a plasma with a loss-cone distribution when the electron temperature exceeds a few tens of kiloelectronvolts. The growth rate is typically a few percent of the electron-cyclotron frequency. The appearance of the...
A more challenging task, however, is fabrication and assembly of electron guns operating at thousands of volts and temperatures often exceeding 1000℃. Electron gun assembly, especially for thermionic guns, is still primarily a manual process. Because the electron gun operates at a high negative ...
If frequencies near the threshold are used, then for fields of 3×105 volts cm-1 the periodic term has a magnitude of about four percent of the nonperiodic part of the current. If the photoelectric threshold frequency for zero field is used to eject the electrons, the resultant plot of ...