The Kaluza-Klein monopole in a massive IIA background

We construct the effective action of the KK monopole in a massive Spe IIA background. We follow two approaches. First we construct a massive M-theory KK monopole from which the IIA monopole is obtained by double dimensional reduction. This eleven-dimensional monopole contains two isometries: one under translations of the Taub-NUT coordinate and the other under massive transformations of the embedding coordinates. Secondly, we construct the massive T-duality rules that map the Type IIB NS5-brane onto the massive Type IIA KK monopole. This provides a check of the action constructed from eleven dimensions. (C) 1999 Elsevier Science B.V.