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arXiv · 1603.04790

One-loop superstring six-point amplitudes and anomalies in pure spinor superspace

Carlos R. Mafra·Oliver Schlotterer
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Abstract

We present the massless six-point one-loop amplitudes in the open and closed superstring using BRST cohomology arguments from the pure spinor formalism. The hexagon gauge anomaly is traced back to a class of kinematic factors in pure spinor superspace which were recently introduced as BRST pseudo-invariants. This complements previous work where BRST invariance arguments were used to derive the non-anomalous part of the amplitude. The associated worldsheet functions are non-singular and demonstrated to yield total derivatives on moduli space upon gauge variation. These cohomology considerations yield an efficient organizing principle for closed-string amplitudes that match expectations from S-duality in the low-energy limit.

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Carlos R. Mafra, Oliver Schlotterer. 2016-05-04. One-loop superstring six-point amplitudes and anomalies in pure spinor superspace. https://doi.org/10.1007/jhep04(2016)148

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