1,563 research outputs found
Supersymmetric D3/D7 for holographic flavors on curved space
We derive a new class of supersymmetric D3/D7 brane configurations, which
allow to holographically describe N=4 SYM coupled to massive N=2 flavor degrees
of freedom on spaces of constant curvature. We systematically solve the
-symmetry condition for D7-brane embeddings into AdS-sliced
AdSS, and find supersymmetric embeddings in a simple closed form.
Up to a critical mass, these embeddings come in surprisingly diverse families,
and we present a first study of their (holographic) phenomenology. We carry out
the holographic renormalization, compute the one-point functions and attempt a
field-theoretic interpretation of the different families. To complete the
catalog of supersymmetric D3/D7 configurations, we construct analogous
embeddings for flavored N=4 SYM on S and dS.Comment: 37 pages, 9 figure
Modelling the Spoon IRS diagnostic diagram
We explore whether our models for starbursts, quiescent star-forming galaxies
and for AGN dust tori are able to model the full range of IRS spectra measured
with Spitzer. The diagnostic plot of 9.7 mu silicate optical depth versus 6.2
mu PAH equivalent width, introduced by Spoon and coworkers in 2007, gives a
good indication of the age and optical depth of a starburst, and of the
contribution of an AGN dust torus. However there is aliasing between age and
optical depth at later times in the evolution of a starburst, and between age
and the presence of an AGN dust torus.
Modeling the full IRS spectra and using broad-band 25-850 mu fluxes can help
to resolve these aliases. The observed spectral energy distributions require
starbursts of a range of ages with initial dust optical depth ranging from
50-200, optically thin dust emission ('cirrus') illuminated by a range of
surface brightnesses of the interstellar radiation field, and AGN dust tori
with a range of viewing angles.Comment: Accepted for publication by MNRAS. 8 pages, 10 figure
- …