# Marginal Solutions for the Superstring

## TL;DR

This paper presents the first nonsingular analytic solutions for open superstring field theory that describe marginal deformations, revealing a duality with bosonic string solutions and advancing understanding of superstring backgrounds.

## Contribution

It constructs a novel class of analytic solutions for superstring field theory that are dual to bosonic solutions, specifically for marginal deformations with on-shell vertex operators.

## Key findings

- First nonsingular analytic superstring solutions for marginal deformations.
- Discovery of a duality between superstring and bosonic string solutions.
- Solutions describe deformations generated by on-shell vertex operators with vanishing operator products.

## Abstract

We construct a class of analytic solutions of WZW-type open superstring field theory describing marginal deformations of a reference D-brane background. The deformations we consider are generated by on-shell vertex operators with vanishing operator products. The superstring solution exhibits an intriguing duality with the corresponding marginal solution of the {\it bosonic} string. In particular, the superstring problem is ``dual'' to the problem of re-expressing the bosonic marginal solution in pure gauge form. This represents the first nonsingular analytic solution of open superstring field theory.