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N=2 Sigma Models for Ramond-Ramond Backgrounds

Nathan Berkovits
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Abstract

Using the U(4) hybrid formalism, manifestly N=(2,2) worldsheet supersymmetric sigma models are constructed for the Type IIB superstring in Ramond-Ramond backgrounds. The Kahler potential in these N=2 sigma models depends on four chiral and antichiral bosonic superfields and two chiral and antichiral fermionic superfields. When the Kahler potential is quadratic, the model is a free conformal field theory which describes a flat ten-dimensional target space with Ramond-Ramond flux and non-constant dilaton. For more general Kahler potentials, the model describes curved target spaces with Ramond-Ramond flux that are not plane-wave backgrounds. Ricci-flatness of the Kahler metric implies the on-shell conditions for the background up to the usual four-loop conformal anomaly.

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Nathan Berkovits. 2002-10-08. N=2 Sigma Models for Ramond-Ramond Backgrounds. https://doi.org/10.1088/1126-6708%2F2002%2F10%2F071

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