Black Rings in Taub-NUT and D0-D6 interactions

TL;DR

This paper studies the interactions and bound states of D0 and D6 branes with B-fields and thermal excitations, revealing conditions for stability and constructing black ring solutions in Taub-NUT spaces.

Contribution

It introduces new solutions for black rings in Taub-NUT spaces with D0-D6 brane configurations, including effects of B-fields and thermal excitations.

Findings

D0 and D6 branes repel at non-zero separation without B-fields.

Large B-fields or thermal excitations lead to stable bound states.

Thermally excited D0 branes form black rings in Taub-NUT.

Abstract

We analyze the dynamics of neutral black rings in Taub-NUT spaces and their relation to systems of D0 and D6 branes in the supergravity approximation. We employ several recent techniques, both perturbative and exact, to construct solutions in which thermal excitations of the D0-branes can be turned on or off, and the D6-brane can have $B$-fluxes turned on or off in its worldvolume. By explicit calculation of the interaction energy between the D0 and D6 branes, we can study equilibrium configurations and their stability. We find that although D0 and D6 branes (in the absence of $B$ fields, and at zero temperature) repeal each other at non-zero separation, as they get together they go over continuosly to an unstable bound state of an extremal singular Kaluza-Klein black hole. We also find that, for $B$-fields larger than a critical value, or sufficiently large thermal excitation, the D0 and D6 branes form stable bound states. The bound states with thermally excited D0 branes are black rings in Taub-NUT, and we provide an analysis of their phase diagram.