On Exact Noncommutative BPS Solitons

We construct new exact BPS solitons in various noncommutative gauge theories by the gauge'' transformation of known BPS solitons. This gauge’’ transformation introduced by Harvey, Kraus and Larsen adds localized solitons to the known soliton. These solitons include, for example, the bound state of a noncommutative Abelian monopole and N fluxons at threshold. This corresponds, in superstring theories, to a D-string which attaches to a D3-brane and N D-strings which pierce the D3-brane, where all D-strings are parallel to each other.