Bremsstrahlung, X rays

A consequence of absorption of X rays is the inner shell ionization of the absorbing atoms and the subsequent generation of characteristic X rays from the absorbing atoms, called secondary fluorescence, which raises the generated intensity over that produced by the direct action of the beam electrons. Secondary fluorescence can be induced by both characteristic and bremsstrahlung X rays. Both effects are compo-sitionally dependent. 

Bremsstrahlung—X rays that are produced when a charged particle accelerates (speeds up, slows down, or changes direction) in the strong field of a nucleus. 

R. Birch and M. Marshall, Computation of bremsstrahlung x-ray spectra and comparison with spectra measure with a Ge(Li) detector, Phys. Med. Biol., 24 (1979) 505-517. 

Figure 4 Microdosimetric distributions as a function of lineal energy in a 2-gm equivalent spherical detector. The solid line is a spectrum for cobalt-60 y-rays, and the dashed and dotted lines are the spectra for 10- and 15-MeV bremsstrahlung x-rays.

In addition to providing electron beams with 5 and 10 MeV electron energy outputs for usual EB applications, Rhodotron can be used to produce bremsstrahlung x-rays from a metallic target that can be used for industrial applications. ° Rhodotron is particularly suitable for applications that need a powerful beam (30-200 kW) in the energy range of 1 to 10 MeV. ... 

The absorption of the p particles of by aluminium is plotted in Fig. 6.7. The form of the absorption curve is due to the continuous energy distribution of the P particles and the scattering of the p radiation in the absorber. At the end of the absorption curve a nearly constant intensity of bremsstrahlung (X rays) is observed. By extrapolation of the absorption curve the maximum range Rmax of the P particles can be found. In practice, this extrapolation is carried out by subtraction of the bremsstrahlung and extension of the curve to 10 /q (Fig. 6.7). 

M. TAKEHISA, T. SAITO, T. TAKAHASHI, Y. SATO, T. SATO, Characteristics of a Contract Electron Beam and Bremsstrahlung (X ray) Irradiation Facility of Radia Industry, Radiation Physics and Chemistry, Vol. 42, Nos. 1-3, pp. 495-498, 1993. 

The hot substrate can emit a substantial IR and UV radiation through blackbody emission, as well as some Bremsstrahlung x-ray radiation... 

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. 

In the following example, gasoline was irradiated with the bremsstrahlung x-rays from a 2 MeV electron beam (Zaikin and Zaikina 2007). The experiments have shown that radiation-enhanced isomerization became especially pronounced when heavy aromatic hydrocarbons were added to relatively lighter feedstock and this mixture was irradiated with moderate x-ray doses. In these experiments, heavy residua of bitumen radiation processing were used as additional agents for enhanced isomerization. 

FIGURE 15.5 Fractional contents of gas-condensate gasoline after Bremsstrahlung x-ray irradiation. GCG, gas-condensate gasoline. 

As the penetrating energetic electrons are deeelerated by atoms and moleeules, they emit Bremsstrahlung X-rays, which can penetrate down to an altitude of 30 km. A balloon-borne X-ray deteetor is needed to observe it. Satellite-bome X-ray detectors have recently succeeded in obtaining global X-ray images of the aurora from above the north polar region. 

Since most of the fusion power output from an advanced-fuel reactor is in the form of bremsstrahlung x-rays, the heat load on the rings and on the first wall must be considered carefully. The... 

Several different types of source have been employed for the excitation of characteristic X-ra-diation, including those based on electrons, X rays, ) rays, protons, and synchrotron radiation. Sometimes a bremsstrahlung X-ray source is used to generate specific X-radiation from an intermediate pure element sample, called a secondary flu-... 

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