Tri-Sasaki 7-metrics fibered over the QK limit of the Plebanski-Demianski metrics
Abstract
Description
We consider a family of conical hyperkahler 8-metrics and we find the corresponding tri-Sasaki 7-metrics. We find in particular, a 7-dimensional fibration over the AdS-Kerr-Newmann-Taub-Nut solutions which is tri-Sasaki, and we consider several limits of the parameters of this solution. We also find an squashed version of these metrics, which is of weak $G_2$ holonomy. Construction of supergravity backgrounds is briefly discussed, in particular examples which do not possess $AdS_4$ near horizon limit.
20 pages, no figures, two references corrected
20 pages, no figures, two references corrected