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arXiv · 1812.10969

Towards the n-point one-loop superstring amplitude I: Pure spinors and superfield kinematics

Carlos R. Mafra·Oliver Schlotterer
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Abstract

This is the first installment of a series of three papers in which we describe a method to determine higher-point correlation functions in one-loop open-superstring amplitudes from first principles. In this first part, we exploit the synergy between the cohomological features of pure-spinor superspace and the pure-spinor zero-mode integration rules of the one-loop amplitude prescription. This leads to the study of a rich variety of multiparticle superfields which are local, have covariant BRST variations, and are compatible with the particularities of the pure-spinor amplitude prescription. Several objects related to these superfields, such as their non-local counterparts and the so-called BRST pseudo-invariants, are thoroughly reviewed and put into new light. Their properties will turn out to be mysteriously connected to products of one-loop worldsheet functions in packages dubbed "generalized elliptic integrands", whose prominence will be seen in the later parts of this series of papers.

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Carlos R. Mafra, Oliver Schlotterer. 2018-12-28. Towards the n-point one-loop superstring amplitude I: Pure spinors and superfield kinematics. https://doi.org/10.1007/jhep08(2019)090

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