Abstract
The M T2, or “s-transverse mass”, statistic was developed to associate a parent mass scale to a missing transverse energy signature, given that escaping particles are generally expected in pairs, while collider experiments are sensitive to just a single transverse momentum vector sum. This document focuses on the generalized \( {\tilde{M}}_{\mathrm{T}2} \) extension of that statistic to asymmetric one- and two-step decay chains, with arbitrary child particle masses and upstream missing transverse momentum. It provides a unified theoretical formulation, complete solution classification, taxonomy of critical points, and technical algorithmic prescription for treatment of the \( {\tilde{M}}_{\mathrm{T}2} \) event scale. An implementation of the described algorithm is available for download, and is also a deployable component of the author’s selection cut software package AEACuS (Algorithmic Event Arbiter and Cut Selector). appendices address combinatoric event assembly, algorithm validation, and a complete pseudocode.
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Walker, J.W. A complete solution classification and unified algorithmic treatment for the one- and two-step asymmetric S-transverse mass \( {\tilde{M}}_{\mathrm{T}2} \) event scale statistic. J. High Energ. Phys. 2014, 155 (2014). https://doi.org/10.1007/JHEP08(2014)155
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DOI: https://doi.org/10.1007/JHEP08(2014)155