v 2 2 2 M ar 2 00 2 15 February 2001 hep - ph / 0103014 The Threshold Expansion of the 2 - loop Sunrise Selfmass Master Amplitudes
نویسنده
چکیده
The threshold behavior of the master amplitudes for two loop sunrise self-mass graph is studied by solving the system of differential equations, which they satisfy. The expansion at the threshold of the master amplitudes is obtained analytically for arbitrary masses. ——————————PACS 11.10.-z Field theory PACS 11.10.Kk Field theories in dimensions other than four PACS 11.15.Bt General properties of perturbation theory PACS 12.20.Ds Specific calculations PACS 12.38.Bx Perturbative calculations
منابع مشابه
The Pseudothreshold Expansion of the 2-loop Sunrise Selfmass Master Amplitudes
The values at pseudothreshold of two loop sunrise master amplitudes with arbitrary masses are obtained by solving a system of differential equations. The expansion at pseudothreshold of the amplitudes is constructed and some lowest terms are explicitly presented. ——————————PACS 11.10.-z Field theory PACS 11.10.Kk Field theories in dimensions other than four PACS 11.15.Bt General properties of p...
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The values at pseudothreshold of two loop sunrise master amplitudes with arbitrary masses are obtained by solving a system of differential equations. The expansion at pseudothreshold of the amplitudes is constructed and some lowest terms are explicitly presented. ——————————PACS 11.10.-z Field theory PACS 11.10.Kk Field theories in dimensions other than four PACS 11.15.Bt General properties of p...
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The differential equations for the 2-loop sunrise graph, at equal masses but arbitrary momentum transfer, are used for the analytic evaluation of the coefficients of its Laurent-expansion in the continuous dimension d.
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The 4-th order Runge-Kutta method in the complex plane is proposed for numerically advancing the solutions of a system of first order differential equations in one external invariant satisfied by the master integrals related to a Feynman graph. The particular case of the general massive 2-loop sunrise self-mass diagram is analyzed. The method offers a reliable and robust approach to the direct ...
متن کاملar X iv : h ep - t h / 06 04 11 3 v 2 2 M ay 2 00 6 Dispersive calculation of the massless multi - loop sunrise diagram
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