SANS-linear-fit

for zero concentration extrapolation:

Given $\phi$

$$S=\phi_DS_1+\phi_D^2S_2$$

$$\frac{S}{\phi_D}=S_1+\phi_DS_2$$

Reference paper: Fabrice Cousin, Small angle neutron scattering, Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif-sur-Yvette, France