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Analytic Continuation of Massless Two-Loop Four-Point Functions

T. Gehrmann·E. Remiddi
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Abstract

We describe the analytic continuation of two-loop four-point functions with one off-shell external leg and internal massless propagators from the Euclidean region of space-like $1\to 3$ decay to Minkowskian regions relevant to all $1\to 3$ and $2\to 2$ reactions with one space-like or time-like off-shell external leg. Our results can be used to derive two-loop master integrals and unrenormalized matrix elements for hadronic vector-boson-plus-jet production and deep inelastic two-plus-one-jet production, from results previously obtained for three-jet production in electron--positron annihilation.

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T. Gehrmann, E. Remiddi. 2002-07-01. Analytic Continuation of Massless Two-Loop Four-Point Functions. https://doi.org/10.1016/s0550-3213(02)00569-2

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