Experimental Design of a SANS Diffractometer

The neutron intensity Id Q) scattered by the momentum transfer Q is described in Eq. 2 it is proportional to the incident intensity lo, the sample thickness D, the sample transmission T = ll/h, and the space angle of 

The transmission describes the attenuation of the neutrons non-scattered by the sample, and the macroscopic cross section di7/df2 in units of cm is the quantity to be determined. The caUbration of the macroscopic cross section dE/d 2 in absolute units is usually performed by an additional measurement with a sample of known dYljdQ or by measuring the direct beam in both cases with the same collimator setting [59,60]. 

Scanering Cross Section of an Ideal Polymer Mixture 

To proceed, we define a variable ct with the following meaning. 

With the contrast factor K = Ap /Na determined from the difference of the coherent scattering length density pa,b = of both monomers and 

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