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arXiv · hep-th/0607187

Some Superstring Amplitude Computations with the Non-Minimal Pure Spinor Formalism

Nathan Berkovits·Carlos R. Mafra
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Abstract

We use the non-minimal pure spinor formalism to compute in a super-Poincare covariant manner the four-point massless one and two-loop open superstring amplitudes, and the gauge anomaly of the six-point one-loop amplitude. All of these amplitudes are expressed as integrals of ten-dimensional superfields in a "pure spinor superspace" which involves five $θ$ coordinates covariantly contracted with three pure spinors. The bosonic contribution to these amplitudes agrees with the standard results, and we demonstrate identities which show how the $t_8$ and $ε_{10}$ tensors naturally emerge from integrals over pure spinor superspace.

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Nathan Berkovits, Carlos R. Mafra. 2006-07-25. Some Superstring Amplitude Computations with the Non-Minimal Pure Spinor Formalism. https://doi.org/10.1088/1126-6708%2F2006%2F11%2F079

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