Emitted electrons

SXES spectroscopy [111] ejects K electrons and the spectrum of the resulting x-rays is measured Spectroscopy of Emitted Electrons state of adsorbed molecules surface composition... 

EXAFS Extended x-ray absorption fine structure [177, 178] Variation of x-ray absorption as a function of x-ray energy beyond an absorption edge the probability is affected by backscattering of the emitted electron from adjacent atoms Number and interatomic distance of surface atoms... 

Such ideal low mean free paths are the basis of FEED, the teclmique that has been used most for detennining surface structures on the atomic scale. This is also the case of photoelectron diffraction (PD) here, the mean free path of the emitted electrons restricts sensitivity to a similar depdi (actually double the depth of FEED, since the incident x-rays in PD are only weakly adenuated on this scale). 

No collector sHt is fitted, and the full width of the ion beam falls onto microchaimel plates which emit electrons. The emitted electrons strike a phosphor coating on the end of a fiber-optic cable (see Fiber optics). The phosphor emits photons which travel along the cable to the photodiode array. 

Pauli proposed that two particles were emitted, and Fermi called the second one a neutrino, V. The complete process therefore is n — p -H e 9. Owing to the low probabiHty of its interacting with other particles, the neutrino was not observed until 1959. Before the j3 -decay takes place there are no free leptons, so the conservation of leptons requires that there be a net of 2ero leptons afterward. Therefore, the associated neutrino is designated an antineutrino, 9-, that is, the emitted electron (lepton) and antineutrino (antilepton) cancel and give a net of 2ero leptons. 

Field emission applicable to flat-panel display is one of the most advanced and energetically studied applications of CNTs. The apparatus is illustrated in Fig. 12 along with pictures of closed-tips of MWCNTs. In spite of their high workfunction (4..3 eV for MWCNTs [39]), CNTs emit electrons from their tips when high voltages (100-1000 V) are applied between the metal grid of the accelerator and the CNT film which are separated by 20 im [38]. 

Leuchtelektron, n. emitting electron, optical electron photo-electron, leuchten, v.t. give light, shine, glow, luminesce. 

Photoemission is the property of some materials to emit electrons when light falls on them. These materials are used as a cathode and an anode collects the electrons. One application is in the photomultiplier unit that is used in counters. 

Electron beam sterilisation is a high-voltage potential established between a cathode and an anode in an evacuated tube. The cathode emits electrons, as a cathodic ray or electron beam. A high intensity of electrons is produced. These electrons are accelerated to extremely high velocities. These accelerated electron intensities have great potential as a bacteriocide. Most electron beams operate in a vacuum. As a result the unwanted organisms in the media vanish and the media is sterilised. 

Above the threshold frequency, the number of emitted electrons increases with the light s intensity, but the kinetic energy per electron does not depend on the light s intensity. 

Laser flash experiments were also carried out with Q-CdS sols, in which the emission of hydrated electrons was observed The quantum yield was significantly greater than in similar experiments with larger particles of yellow CdS (Sect. 3.7). The electron emission was attributed to the interaction of two excitonic states in a particle produced during the flash CdS(e — h >2 CdS(h" ) + e q. The emitted electrons disappeared after the laser flash within 10 ps. After this time a long-lived absorption remained which was identical with the above-mentioned absorption of holes produced by OH radicals in the pulse radiolysis experiment. 

High-energy radation can be imaged with a-Si H, either directly or via a converter [3], A thick film is required for direct detection, due to the weak interaction of the radiation with the material. A converter usually is a phosphor, which emits in the visible, and thin a-Si H films are needed. X-rays with an energy up to 100 keV eject the electrons from the inner atomic core levels to high levels in the conduction band. The emitted electrons create electron-hole pairs due to ionization. These pairs can be detected in the same way as in p-i-n photodiodes. 

---