Stable massive states in (1 + 1)-dimensional noncommutative open string theory

We study the case of open string theory on a Dl-brane in a critical electric field. It was argued by Klebanov and Maldacena that the massless open string modes of this theory decouple from the massive modes, corresponding to a decoupling of the U(l) degrees of freedom in the U(AO gauge theory dual. To provide further support for the decoupling, we present several examples of open string disk amplitudes. Because of the decoupling, many of the massive open string states are stable, indicating the presence of a number of correspondingly stable states in the gauge theory. We provide a lengthy list of these stable states. However, when the theory is compactified in the spatial direction of the electric field, we demonstrate that such sufficiently massive states may decay into 'wound-closed strings.