5 research outputs found
Seven-branes and Supersymmetry
We re-investigate the construction of half-supersymmetric 7-brane solutions
of IIB supergravity. Our method is based on the requirement of having globally
well-defined Killing spinors and the inclusion of SL(2,Z)-invariant source
terms. In addition to the well-known solutions going back to Greene, Shapere,
Vafa and Yau we find new supersymmetric configurations, containing objects
whose monodromies are not related to the monodromy of a D7-brane by an SL(2,Z)
transformation.Comment: 31 pages, 3 figure
Q7-branes and their coupling to IIB supergravity
We show how, by making use of a new basis of the IIB supergravity
axion-dilaton coset, SL(2,R)/SO(2), 7-branes that belong to different conjugacy
classes of the duality group SL(2,R) naturally couple to IIB supergravity with
appropriate source terms characterized by an SL(2,R) charge matrix Q. The
conjugacy classes are determined by the value of the determinant of Q. The
(p,q) 7-branes are the branes in the conjugacy class detQ = 0. The 7-branes in
the conjugacy class detQ > 0 are labelled by three numbers (p,q,r) which
parameterize the matrix Q and will be called Q7-branes. We construct the full
bosonic Wess--Zumino term for the Q7-branes. In order to realize a gauge
invariant coupling of the Q7-brane to the gauge fields of IIB supergravity it
is necessary to introduce an SL(2,R) doublet of two distinct Born--Infeld
fields on the Q7-brane world-volume.Comment: 31 pages, Latex fil