A ripple with a symmetric rectangular profile that is uniform in $x$-direction.
Box(L, W, H)
BarGauss(L, W, H)
BarLorentz(L, W, H)
Parameters:
Bar with rectangular longitudinal profile is equvalent to Box particle.
As for any other Form factor.
Class Bar inherits from the interface class IFormfactor .
Form factor is computed as
$$ F(\mathbf{q}) = f_\parallel(q_x) f_\bot(q_y,q_z), $$
where $$ f_\bot(q_y,q_z) = WH \space \exp\Big(iq_{z}\dfrac{H}{2}\Big) \space \text{sinc}\Big(q_{y}\dfrac{W}{2}\Big) \space \text{sinc}\Big(q_{z}\dfrac{H}{2}\Big).$$
Corresponding factor $ f_\parallel(q_x) $ is chosen according to longitudinal profile.
Volume has been validated against $$V=LWH.$$
Scattering by uncorrelated, oriented “BarLorentz” ripples for horizontal incidence. Rotation around $z$ axis:
Generated by Examples/ff/BarLorentz.py .