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arXiv · 2203.14346

A new approach for amplitudes with multiple fermion lines

Feng Zhang·Bin Gong·Jian-Xiong Wang
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Abstract

A new approach for tree-level amplitudes with multiple fermion lines is presented. It mainly focuses on the simplification of fermion lines. By calculating two vectors recursively without any matrix multiplications, the result of a fermion line is reduced to a very compact form depending only on the two vectors. The comparisons with other packages are presented, and the results show that our package FDC gives a very good performance in the processes of multiple fermion lines with this new approach and some other improvements. A further comparison with WHIZARD shows that this new approach has a competitive efficiency in computing pure amplitude square without phase space integration.

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Feng Zhang, Bin Gong, Jian-Xiong Wang. 2022-03-27. A new approach for amplitudes with multiple fermion lines. https://doi.org/10.1088/1674-1137%2Fac6a4e

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