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arXiv · 2511.22516

Accurate simulations of magnetic excitations in the neutron simulation package McStas

Silas B. Schack·Kristine M. L. Krighaar·Emma Y. Lenander·Kim Lefmann
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Abstract

A new component for the accurate simulation of neutron scattering from magnetic excitations has been developed for the neutron ray-tracing software McStas. The component SpinWave_BCO simulates inelastic neutron scattering from ferro-, antiferro-, and altermagnetic excitations in a body-centered orthorhombic crystal structure, where the dispersion relation and scattered neutron intensities are derived using linear spin wave theory. Data from a simulated Triple-Axis Spectrometer with an extremely high resolution have been verified by direct comparison with theory and by comparison to data simulated using the package SpinW. The component serves as a proof-of-concept for the implementation of a more general linear spin wave component in McStas.

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Silas B. Schack, Kristine M. L. Krighaar, Emma Y. Lenander, Kim Lefmann. 2025-11-27. Accurate simulations of magnetic excitations in the neutron simulation package McStas. https://arxiv.org/abs/2511.22516

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