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arXiv · 2403.07981

SPINAS: Spinor Amplitude Subroutines for Constructive Diagram Evaluations

Neil Christensen
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Abstract

SPINAS is a C++ package created for the implementation and numerical computation of phase-space points of constructive amplitudes in particle physics. This package contains a suite of classes and methods for handling particles, propagators, spinor products, and processes. SPINAS is structured to offer straightforward usability while ensuring maximum efficiency. This is achieved through a design that emphasizes the storage and reuse of intermediate results within amplitude calculations for each phase-space point. We include a user guide describing how to use the components, a complete example of how to use SPINAS for a scattering amplitude, a discussion of the design and implementation useful for those wishing to contribute, and a discussion of our validation of this package, including both a validation of individual components of the package and a comparison of a complete set of Standard Model processes with Feynman diagrams.

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Neil Christensen. 2024-03-12. SPINAS: Spinor Amplitude Subroutines for Constructive Diagram Evaluations. https://arxiv.org/abs/2403.07981

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