Source backscattering factor

To correct properly for this effect, a source backscattering factor (/ ) is defined by... 

Figure 8,15 The source backing material backscatters particles and necessitates the use of a backscattering factor /. ...

How would the result of Prob. 8.9 change if the backscattering factor was known with an error of +1 percent, the efficiency with an error of +0.5 percent, and the source self-absorption factor with an error of 1 percent ... 

A point isotropic source is located at the center of a hemispherical 2tr counter. The efficiency of this detector tor the particles emitted by the source is 85 percent. The saturation backscattering factor is 1.5. The background is 25 + 1 counts/min. What is the strength of the source if 3000 counts are recorded in 1 min What is the standard error of this measurement ... 

The major source of uncertainty in parameter determination by EXAFS analysis arises from the correlation that exists between the coordination number (Nj) and the Debye-Waller factor (crj) for each shell. This correlation occurs through the amplitude of the backscattered wave [Eq. (4)] and results in the uncertainty in Nj being 25%. The primary manifestation of is in the relative phases of the outgoing and backscattered waves and, although Rj is strongly correlated to... 

The subject of relative and absolute measurements is presented in Chap. 8. The solid angle (geometry factor) between source and detector and effects due to the source and the detector, such as efficiency, backscattering, and source self-absorption are all discussed in detail. 

If the beam power Wq is absorbed at the target surface, the temperature rise v is given by Eq. (26.123). This must be corrected for the effects of backscatter and source disper to give Uq. In this process, the power retention factor p is taken from Fig. 26.39 for a given material Z, and the temperature rise o is taken from Fig. 26.40 for calculated from Eqs. (26.114) and (26.115). With the values of Vq, p, and u , the true temperature rise Ug at the berm center is found from Uo = i[Pg.695]

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