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arXiv · 1006.3952

Unstable-particles pair production in modified perturbation theory in NNLO

M. L. Nekrasov
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Abstract

We consider pair production and decay of fundamental unstable particles in the framework of a modified perturbation theory (MPT), which treats resonant contributions of unstable particles in the sense of distributions. The cross-section of the process is calculated within the NNLO of the MPT in a model that admits exact solution. Universal massless-particles contributions are taken into consideration. The calculations are carried out by means of FORTRAN code with double precision, which ensures per mille accuracy of computations. A comparison of the outcomes with the exact solution reveals an excellent convergence of the MPT series at the energies close to and above the maximum of the cross-section. Near the maximum of the cross-section the discrepancy of the NNLO approximation makes up a few per mille.

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M. L. Nekrasov. 2010-06-20. Unstable-particles pair production in modified perturbation theory in NNLO. https://arxiv.org/abs/1006.3952

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