### Polarized SANS

This example shows how to simulate polarized SANS with BornAgain, using the Born Approximation.

The main difference between simulating GISAS and SAS in BornAgain is the presence of only a single layer in the multilayer object. This triggers the software to calculate the differential scattering cross section in the Born Approximation.

In this example, a sample with a magnetic core-shell particle is constructed. Beam and detector are setup to detect the spin-flip scattering channel and the result of this simulation is plotted as usual.

  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 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76  #!/usr/bin/env python3 """ Simple example demonstrating how polarized SANS experiments can be simulated with BornAgain. """ import bornagain as ba from bornagain import ba_plot as bp, deg, nm, R3 def get_sample(): """ A sample with a magnetic core-shell particle in a solvent. """ # Materials B = R3(0, 1e7, 0) material_Core = ba.RefractiveMaterial("Core", 6e-06, 2e-08, B) material_Shell = ba.RefractiveMaterial("Shell", 1e-07, 2e-08) material_Solvent = ba.RefractiveMaterial("Solvent", 5e-06, 0) # Form factors ff_1 = ba.Sphere(10*nm) ff_2 = ba.Sphere(12*nm) # Particles particle_1 = ba.Particle(material_Core, ff_1) particle_1_position = R3(0, 0, 2*nm) particle_1.translate(particle_1_position) particle_2 = ba.Particle(material_Shell, ff_2) # Core shell particles particle = ba.CoreAndShell(particle_1, particle_2) # Particle layouts layout = ba.ParticleLayout() layout.addParticle(particle) layout.setTotalParticleSurfaceDensity(0.01) # Layers layer = ba.Layer(material_Solvent) layer.addLayout(layout) # Sample sample = ba.MultiLayer() sample.addLayer(layer) return sample def get_simulation(sample): """ A polarized SANS simulation """ n = 200 # Beam from above (perpendicular to sample): beam = ba.Beam(1e9, 0.4*nm, 9*deg) # Detector opposite to source: detPos = 2000 # distance from sample center to detector in mm detWid = 500 # detector width in mm detector = ba.RectangularDetector(n, detWid, n, detWid) detector.setPerpendicularToDirectBeam(detPos, detWid/2, detWid/2) beam.setPolarization(R3(0, 1, 0)) detector.setAnalyzer(R3(0, -1, 0)) return ba.ScatteringSimulation(beam, sample, detector) if __name__ == '__main__': bp.parse_args(units=ba.Coords_QSPACE) sample = get_sample() simulation = get_simulation(sample) result = simulation.simulate() bp.plot_simulation_result(result) 
auto/Examples/scatter2d/PolarizedSANS.py