### Cylinders in Distorted Wave Born Approximation

Scattering from a monodisperse distribution of cylindrical particles using the Distorted Wave Born Approxiamtion (DWBA).

This example is similar to the simulation Cylinders in Born Approximation, but now the particles sit on top of a substrate. Therefore incoming and scattered waves are distorted by reflections from the substrate surface, as described by the DWBA.

• The distribution of cylinders is monodisperse with heights and radii of $5$ nm.
• The wavelength is equal to $1$ $\unicode{x212B}$.
• The incident angles are equal to $\alpha_i = 0.2 ^{\circ}$ and $\phi_i = 0^{\circ}$.
• No interference effects from inter-particle correlations (dilute-particles approximation).
  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57  """ Cylinder formfactor in DWBA """ import bornagain as ba from bornagain import deg, angstrom, nm def get_sample(): """ Returns a sample with cylinders on a substrate. """ # defining materials m_ambience = ba.HomogeneousMaterial("Air", 0.0, 0.0) m_substrate = ba.HomogeneousMaterial("Substrate", 6e-6, 2e-8) m_particle = ba.HomogeneousMaterial("Particle", 6e-4, 2e-8) # collection of particles cylinder_ff = ba.FormFactorCylinder(5*nm, 5*nm) cylinder = ba.Particle(m_particle, cylinder_ff) particle_layout = ba.ParticleLayout() particle_layout.addParticle(cylinder, 1.0) air_layer = ba.Layer(m_ambience) air_layer.addLayout(particle_layout) substrate_layer = ba.Layer(m_substrate) multi_layer = ba.MultiLayer() multi_layer.addLayer(air_layer) multi_layer.addLayer(substrate_layer) return multi_layer def get_simulation(): """ Returns a GISAXS simulation with beam and detector defined """ simulation = ba.GISASSimulation() simulation.setDetectorParameters(200, -2.0*deg, 2.0*deg, 200, 0.0*deg, 2.0*deg) simulation.setBeamParameters(1.0*angstrom, 0.2*deg, 0.0*deg) return simulation def run_simulation(): """ Runs simulation and returns intensity map. """ simulation = get_simulation() simulation.setSample(get_sample()) simulation.runSimulation() return simulation.result() if __name__ == '__main__': result = run_simulation() ba.plot_simulation_result(result) 
CylindersInDWBA.py