The final energy dependent term

Differentiating the final energy dependent term in Eq. (A3.2), with respect to Ef. 

Where 02 is the divergence of the beam scattered from the sample, 03 is the divergence of the beam diffracted by the analyser, as seen at the detector and /g is the mosaic spread of the graphite analyser. 

Ws and wj are the width (in m) of the sample and the detector respectively. The thickness of the graphite in Eq. (A3.20) and the mosaic spread in Eq. (A3.21) are both doubled since the neutron traverses the graphite twice as it enters and leaves the analyser. 

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