String Scattering from D-branes in Type 0 Theories

TL;DR

This paper derives covariant two-point scattering amplitudes involving tachyons and massless strings from D-branes in type 0 theories, revealing tachyon couplings in the D-brane world-volume action.

Contribution

It provides explicit covariant expressions for scattering amplitudes and identifies the tachyon as an overall coupling in the Born-Infeld action, advancing understanding of D-brane dynamics in type 0 theories.

Findings

Tachyon couples as an overall factor in the Born-Infeld action.

Explicit covariant amplitudes for tachyon and massless string scattering.

Identification of world-volume couplings involving tachyons.

Abstract

We derive fully covariant expressions for all two-point scattering amplitudes involving closed string tachyon and massless strings from Dirichlet brane in type 0 theories. The amplitude for two massless D-brane fluctuations to produce closed string tachyon is also evaluated. We then examine in detail these string scattering amplitudes in order to extract world-volume couplings of the tachyon with itself and with massless fields on a D-brane. We find that the tachyon appears as an overall coupling function in the Born-Infeld action.