Absorbed energy density, calculation

Figure 6. Calculated absorbed energy density due to forward and backward scattered electrons. Zq is the penetration depth in a 0.4-nm PMMA film which is coated on an Al substrate. The electron energy used is 20 keV. (Reproduced with permission from Ref. 4j...

Figure 7. Calculated absorbed energy density as a function of radial distance for an infinitessimal beam. The energy density at the midpoint in a 0.5imaging resist layer in SLR and various MLR configurations is plotted. (Reproduced with permission from Ref. 6J...

The zero-point oscillations of the energy density of plane waves of photons have the same magnitude everywhere. In contrast, those calculated in the presence of a singular point (source or absorber) manifest spatial inhomogeneity. Precisely, the vacuum noise is concentrated in some vicinity of the singular point. 

Fig. 3.23 Left-. Calculated relationship between the thickness of an alteration rind and/or dust coating on a rock and the amount of 15.0-keV radiation absorbed in the rind/coating for densities of 0.4, 2.4, and 4.0 g cm [57]. The bulk chemical composition of basaltic rock was used in the calculations, and the 15.0 keV energy is approximately the energy of the 14.4 keV y-ray used in the Mossbauer experiment. The stippled area between densities of 2.4 and 4.0 g cm is the region for dry bulk densities of terrestrial andesitic and basaltic rocks [58]. The stippled area between densities of 0.1 and 0.4 g cm approximates the range of densities possible for Martian dust. The density of 0.1 g cm is the density of basaltic dust deposited by air fall in laboratory experiments [59]. Right Measured spectra obtained on layered laboratory samples and the corresponding simulated spectra, from top to bottom 14.4 keV measured (m) 14.4 keV simulated (s) 6.4 keV measured (m) and 6.4 keV simulated (s). All measurements were performed at room temperature. Zero velocity is referenced with respect to metallic iron foil. Simulation was performed using a Monte Carlo-based program (see [56])...

With analogy to electric circuits, a transfer function of the antenna can be calculated and the response of the antenna to an incoming wave obtained. The output signal is usually expressed as antenna cross-section. It is defined as the ratio between the total energy absorbed by the antenna and the incident spectral density function of the incident wave. In the case of Nautilus antenna (2300 kg, 3 x 0.6 m) the cross-section is of the order of 10 25m2 Hz. 

In order to handle radioisotopes safely it is necessary, among other things, to define fairly carefully the penetrating power of the radiation emitted by any isotope. Alpha particles, having only a relatively limited number of energy levels, are absorbed by contact with other atoms. The absorbing power of a material is referred to in terms of its equivalent thickness. The thickness required can be calculated by dividing the equivalent thickness by the density of the material. 

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