Download BornAgain User Manual - Scientific Computing Group

Contents
Introduction
About BornAgain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Typesetting conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1 Online documentation
1.1 Download and installation . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Further online information . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Registration, contact, discussion forum . . . . . . . . . . . . . . . . . . .
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2 Small-angle scattering and the Born approximation
2.1 Coherent neutron propagation . . . . . . . . . . . . . .
2.2 Neutron scattering in Born approximation . . . . . . .
2.2.1 The Born expansion . . . . . . . . . . . . . . .
2.2.2 Far-field approximation . . . . . . . . . . . . .
2.2.3 Differential cross section . . . . . . . . . . . . .
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3 Grazing-incidence scattering and the distorted wave Born approximation
3.1 Scattering under grazing incidence . . . . . . . . . . . . . . . . . . . . .
3.1.1 Wave propagation in 2 + 1 dimensions . . . . . . . . . . . . . . .
3.1.2 Distorted-wave Born approximation (DWBA) . . . . . . . . . . .
3.2 Absorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4 DWBA for multilayer systems
4.1 Scalar case . . . . . . . . . . . . . . . . . . . . . . . . .
4.1.1 Wave propagation and DWBA matrix element .
4.1.2 Wave propagation across layers . . . . . . . . . .
4.1.3 Damped waves in absorbing media or under total
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reflection
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5 Particle Assemblies
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5.1 Embedded particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
A Some proofs
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A.1 Source–detector reciprocity for scalar waves . . . . . . . . . . . . . . . . 28
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