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arXiv · hep-th/0309028

S-matrix elements and covariant tachyon action in type 0 theory

Mohammad R. Garousi
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Abstract

We evaluate the sphere level S-matrix element of two tachyons and two massless NS states, the S-matrix element of four tachyons, and the S-matrix element of two tachyons and two Ramon-Ramond vertex operators, in type 0 theory. We then find an expansion for theses amplitudes that their leading order terms correspond to a covariant tachyon action. To the order considered, there are no $T^4$, $T^2(\prt T)^2$, $T^2H^2$, nor $T^2R$ tachyon couplings, whereas, the tachyon couplings $F\bF T$ and $T^2F^2$ are non-zero.

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Mohammad R. Garousi. 2004-01-21. S-matrix elements and covariant tachyon action in type 0 theory. https://doi.org/10.1016/j.nuclphysb.2004.10.055

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