The massive one-loop four-point string amplitude in pure spinor superspace

Carlos R. Mafra

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arXiv · 2508.09930

The massive one-loop four-point string amplitude in pure spinor superspace

Carlos R. Mafra

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Abstract

The open- and closed-string three- and four-point one-loop amplitudes involving massless states and one first-level massive state are computed in pure spinor superspace. For the open string, we show that their one-loop correlators can be rewritten in terms of tree-level kinematic factors. We then analyze the closed string. For three points, this is immediate. For four points, we show that it is possible to rewrite the one-loop closed-string correlator using tree-level kinematic factors, but only for certain combinations of massive and massless states (different for type IIA and IIB).

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Carlos R. Mafra. 2025-08-13. The massive one-loop four-point string amplitude in pure spinor superspace. https://arxiv.org/abs/2508.09930

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