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تسجيل مستخدم جديدThe Two-Loop Infrared Structure of Amplitudes with Mixed Gauge Groups
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William B. Kilgore
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The infrared structure of (multi-loop) scattering amplitudes is determined entirely by the identities of the external particles participating in the scattering. The two-loop infrared structure of pure qcd amplitudes has been known for some time. By computing the two-loop amplitudes for $bar{f},flongrightarrow X$ and $bar{f},flongrightarrow V_1,V_2$ scattering in an $SU(N)times SU(M)times U(1)$ gauge theory, I determine the anomalous dimensions which govern the infrared structure for any massless two-loop amplitude.
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