Non-supersymmetric D1/D5, F/NS5 and closed string tachyon condensation

We construct the intersecting non-supersymmetric (non-susy) D1/D5 solution of type IIB string theory. While, as usual, the solution is charged under an electric two-form and an electric six-form gauge field, it also contains a non-susy chargeless (non-BPS) D0-brane. The S-dual of this solution is the non-susy F/NS5 solution. We show how these solutions nicely interpolate between the corresponding black (or non-extremal) solutions and the Kaluza-Klein (KK) "bubble of nothing" (BON) by continuously changing some parameters characterizing the solutions from one set of values to another. We show, by a time symmetric general bubble initial data analysis, that the final bubbles in these cases are static and stable and the interpolations can be physically interpreted as closed string tachyon condensation. As special cases, we recover the transition of two charge black F-string to BON, considered by Horowitz, and also the transition from AdS$_3$ black hole to global AdS$_3$.