More on WZ action of non-BPS branes

TL;DR

This paper computes a specific string scattering amplitude involving non-BPS branes and demonstrates that its features can be explained by existing effective actions and their higher derivative corrections.

Contribution

It provides a detailed calculation of the disk-level S-matrix for non-BPS branes and matches the results with effective field theories, including higher derivative corrections.

Findings

Infinite tachyon/massless poles are reproduced by the tachyon DBI and WZ actions.

Contact terms match the predictions of effective actions and their corrections.

The momentum expansion confirms the consistency of string amplitudes with effective field theories.

Abstract

We calculate the disk level S-matrix element of one Ramond-Ramond, two gauge fields and one tachyon vertex operators in the world volume of non-BPS branes. We then find the momentum expansion of this amplitude and show that the infinite tachyon/massless poles and the contact terms of this amplitude can be reproduced by the tachyon DBI and the WZ actions, and by their higher derivative corrections.