Supertubes and special holonomy

We obtain a (1/4)-supersymmetric 6-brane solution of IIA supergravity by T-dualizing the supertube recently found. The resulting C-1 electric charge is related to the original D0-brane charge. The uplifted solution to eleven dimensions results to be a purely geometrical configuration. which can be interpreted as a bound state of a Taub-NUT space and a pp-wave. Being the non-trivial part of the metric pseudo-Riemannian, the resulting reduced holonomy group is non-compact and locally isomorphic to a semidirect product of an Abelian four-dimensional group and SU(2). (C) 2002 Elsevier Science B.V. All rights reserved.