Monte Carlo Ray-tracing

Least squares fit of the NAC reference sample synchrotron powder profiles obtained with the Ge(lll) analyzer crystal, (a) NAC (211) Bragg reflection (b) NAC (921) Bragg reflection. The flve other curves are, from left to right, the incident beam source profile, the transfer function of the monochromator, the pure sample profile, the reflection profile of the analyzer, and the axial divergence asymmetry function, respectively. (From Masson, Doryhee, Fitch, by courtesy of J. Appl. Crystallogrfi 

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The second method for calculating the total instrumental function is raytracing simulations, in which the contribution of all possible incident and diffracted rays to the total intensity are treated numericallyLike any pure numerical treatment it is limited in the analysis. In addition, the Monte-Carlo ray-tracing simulations are time-consuming. Nevertheless, ray-tracing simulations provide a reliable calculation of the instrumental function. 

Abstract Recently there has been much interest in the X-ray focusing properties of microch umel plates (MCPs). MCPs with both round and square pores have been shown to focus soft X-rays (Eraser ei al. Nucl.Inst.Meth.A 324 (1993) 404 and Nucl.Inst.Meth.A 334 (1993) 579). In particular, images have been obtained from point sources positioned at the foci of round-pore MCP X-ray lenses for 0.28-17.4 keV X-rays. A Monte Carlo ray trace model has been developed which gives good agreement with experimental images. 

Endruweit A, Long A, Johnson M. Textile composites with integrated optical fibres quantification of the influence of single and multiple fibre bends on the light transmission using a Monte Carlo ray-tracing method. Smart Mater. Struct. 2008 17(1) 1—10. 

Monte Carlo Methods / Ray-tracing Methods Monte Carlo methods are well suited to the thermal radiation problems since the energy travels in photons, having a straight path before interacting with matter. The principle of the Monte Carlo / ray-tracing method is to trace the history of a statistically meaningful number of photons from their point of emission to their point of absorption. 

Within the bed, the radiation is treated by combining the ray tracing with the Monte Carlo method. The conduction through the spheres is allowed by solving for the temperature distribution in a representative sphere for each particle layer in the bed. 

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