Cherenkov radiation

The complete mathematical theory and numerous applications of Cherenkov radiation in various fields, such as optics, nuclear physics, high frequency radio techniques, astrophysics and cosmic rays are discussed in the Ref... 

C. Vavilov-Cherenkov Radiation and Photoradiation Reactions in Tracks... 

The second term in formula (5.23) is nonzero only if p2e(a>) > 1, which is the condition of existence of transversal waves in the medium. These waves are the Vavilov-Cherenkov radiation,211 so that second term gives us the losses of particle s energy on Vavilov-Cherenkov radiation. This radiation is observed in the frequency range where (w) is real [i.e., e2(w) = 0],148 and the absorption is negligible. In this case the second term is independent of b, and the particle s field has the form of waves propagating into infinity. If the absorption is large, the Vavilov-Cherenkov radiation is absorbed in the nearest vicinity of the point where it was produced. 

V. P. Zrelov, Valilov-Cherenkov Radiation and Its Application in High Energy Physics. Atomizdat, Moscow, 1968, Vols. 1 and 2 (in Russian). 

Nanoporous materials are of great interest for example for their photoluminescent properties (silicon) or possible use as templates (alumina). The types of synthesis of these materials are numerous and the etching/ anodization influences the results [27 - 29]. A detailed studied of Cherenkov radiation in nanoporous alumina membranes has been done which explains the existence of low energy peaks around 7-8 eV [30] (Figure 9 left). Whereas for a cylindrical hole in alumina the simulation does not show a peak, a cylindrical shell of alumina does. The Cherenkov radiation is confined in the shell, as in a wave guide, and a peak appears. If an effective... 

Figure 9. Left experimental spectrum obtained in the center of a hole in porous alumina. Right three LELS relativistic simulations. (Reprinted from Surface Science 532-535 Zabala N, Rivacoba, Garcia de Abajo F.J. and Pattantyus A., Cherenkov radiation effects in EELS for nanoporous alumina membranes, 461-467 Copyright (2003) with permission from Elsevier)...

Cherenkov radiation is electromagnetic radiation emitted when a charged particle (such as an electron) passes through an insulator at a constant speed greater than the phase velocity of light in that medium. The characteristic "blue glow" of nuclear reactors is due to Cherenkov radiation. 

Auston DH, Cheung KP, Valdmanis IA, Kleinman DA. Cherenkov radiation from femtosecond optical pulses in electro-optic media. Phys Rev Lett 1984 53(16) 1555—1558. 

Grigoryants VM, Lozovoy W, Chemousov YuD, Shebolaev IV, Arutyunov AV, Anisimov OA, Molin YuN. (1989) Pulse radiolysis system with picosecond time resolution referred to Cherenkov radiation. Radiat Phys Chem 34 349-352. 

Currently, the liquid scintillation counter has been employed not only for the measurement of low energy p emitters, but also for pure P, p-y, and a-emitters and further Cherenkov radiation. The liquid scintillator consists mainly of organic solvent and fluorescent material (i.e. solute), and sometimes a surfactant or other material is added to the solution. The characteristics of the liquid scintillator depend mostly on the sort and amount of these chemicals. The liquid scintillator plays the role of an energy transducer, converting radiation energy into photons. The organic solvent which... 

Less common detection of electrons is by photons emitted during their deceleration in a medium. The two mechanisms are creation of bremsstrahlung (continuous X-ray spectrum) and Cherenkov radiation (visible light). Cherenkov radiation is detected with a PMT bremsstrahlung X rays are detected as discussed below for gamma rays. 

Bremsstrahlung is of interest in radioanalytical chemistry because some of the energy of electrons stopped in detector-shielding material is converted to X rays that can penetrate the shield. Cherenkov radiation permits scintillation counting of radionuclides in plain water samples if the electron energy is sufficiently high and the detection system is sufflciently sensitive. 

Cherenkov radiation Electromagnetic radiation resulting from charged particles traveling in a medium faster than light can travel in the same medium. The deceleration of the particle produces this radiation, which is sometimes seen as the characteristic blue glow at a nuclear reactor. 

Fig. 2 Transmission electron micrographs and co-registered in vivo optical luminescence (Cherenkov radiation) and X-ray transmission images in tumour-bearing mice (1 h and 24 h post-dose, tumours marked with a circle) of Au nanoparticles of varying morphologies including (a) spheres (b) disks (c) rods and (d) cages. Spherical morphologies show the best performance in terms of blood circulation, clearance and tumour uptake compared with disks, rods and cages. Reprinted with permission from Black et al. ACS Nano, 2014, 8(5) 4385-4394. Copyright (2014) American Chemical Society.

One of the properties of Cherenkov radiation is its characteristic of a surface phenomenon which does not conserve the transverse component of the linear momentum. Thus, the ring emission should originate mainly at the surfaces of the self-trapped filaments, and not in their bulk. 

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