November 14, 2005
In string compactification preserving N=1 SUSY, moduli fields are plausible candidates for the messenger of SUSY breaking at low energy scales. In a scenario that moduli-mediated SUSY breaking is significant, the pattern of soft SUSY breaking terms depends crucially on how the light moduli with mass m \lesssim O(8\pi^2 m_{3/2}) are stabilized. We discuss the correspondence between the pattern of soft terms and the stabilization mechanism of light moduli within the framework of 4D effective supergravity which is generalized to include a SUSY-breaking uplifting potential which might be necessary to get the phenomenologically viable de-Sitter (or Minkowski) vacuum. In some special case, light moduli can be stabilized by controllably small perturbative corrections to the K\"ahler potential, yielding the soft terms dominated by the moduli-mediated contribution. In more generic situation, light moduli are stabilized by non-perturbative effects encoded in the superpotential and a quite different pattern of soft terms emerges: the anomaly-mediated soft terms become comparable to the moduli-mediated ones. Such mixed moduli-anomaly mediated soft terms lead to low energy superparticle masses qualitatively different from those of other mediation models such as mSUGRA scenario, gauge-mediation, and anomaly-mediation.
Similar papers 1
September 19, 2008
We discuss the pattern of low energy sparticle spectra which appears in some class of moduli stabilization scenario. In case that light moduli are stabilized by non-perturbative effects encoded in the superpotential and a phenomenologically viable de Sitter vacuum is obtained by a sequestered supersymmetry breaking sector, the anomaly-mediated soft terms become comparable to the moduli-mediated ones, leading to a quite distinctive pattern of low energy spacticle masses dubbed...
March 28, 2005
We examine the structure of soft supersymmetry breaking terms in KKLT models of flux compactification with low energy supersymmetry. Moduli are stabilized by fluxes and nonperturbative dynamics while a de Sitter vacuum is obtained by adding supersymmetry breaking anti-branes. We discuss the characteristic pattern of mass scales in such a set-up as well as some features of 4D N=1 supergravity breakdown by anti-branes. Anomaly mediation is found to always give an important cont...
June 13, 2008
We present a model of supersymmetry breaking in which the contributions from gravity/modulus, anomaly, and gauge mediation are all comparable. We term this scenario "deflected mirage mediation," which is a generalization of the KKLT-motivated mirage mediation scenario to include gauge mediated contributions. These contributions deflect the gaugino mass unification scale and alter the pattern of soft parameters at low energies. In some cases, this results in a gluino LSP and l...
May 11, 2006
We examine the effects of anomalous U(1)_A gauge symmetry on soft supersymmetry breaking terms while incorporating the stabilization of the modulus-axion multiplet responsible for the Green-Schwarz (GS) anomaly cancellation mechanism. In case of the KKLT stabilization of the GS modulus, soft terms are determined by the GS modulus mediation, the anomaly mediation and the U(1)_A mediation which are generically comparable to each other, thereby yielding the mirage mediation patt...
March 27, 2007
A generic lesson of string theory is that the coupling constants of an effective low energy theory are determined by the vacuum values of a set of fields - the so-called moduli - some of which are stabilized at relatively low masses by non-perturbative effects. We argue that the physics of these moduli cannot be separated from the issues of dynamical and gauge mediated supersymmetry breaking. To illustrate this point we present a modified version of the type IIB KKLT model wh...
April 17, 2011
Models with anomalous U(1) gauge symmetry contain various superfields which can have nonzero supersymmetry breaking auxiliary components providing the origin of soft terms in the visible sector, e.g. the U(1) vector superfield, the modulus or dilaton superfield implementing the Green-Schwarz anomaly cancellation mechanism, U(1)-charged but standard model singlet matter superfield required to cancel the Fayet-Iliopoulos term, and finally the supergravity multiplet. We examine ...
April 6, 2005
In some string compactifications, for instance the recently proposed KKLT set-up, light moduli are stabilized by nonperturbative effects at supersymmetric AdS vacuum which is lifted to a dS vacuum by supersymmetry breaking uplifting potential. In such models, soft supersymmetry breaking terms are determined by a specific mixed modulus-anomaly mediation in which the two mediations typically give comparable contributions to soft parameters. Similar pattern of soft terms can ari...
July 1, 2008
We study how two moduli can be stabilized in a Minkowski/de Sitter vacuum for a wide class of string-inspired Supergravity models with an effective Fayet-like Supersymmetry breaking. It is shown under which conditions this mechanism can be made natural and how it can give rise to an interesting spectrum of soft masses, with a relatively small mass difference between scalar and gaugino masses. In absence of a constant superpotential term, the above mechanism becomes completely...
January 6, 2009
We study the influence of anomalous U(1) symmetries and their associated D-terms on the vacuum structure of global field theories once they are coupled to N=1 supergravity and in the context of string compactifications with moduli stabilisation. In particular, we focus on a IIB string motivated construction of the ISS scenario and examine the influence of one additional U(1) symmetry on the vacuum structure. We point out that in the simplest one-Kahler modulus compactificatio...
June 19, 2001
The region of moduli space of string theories which is most likely to describe the "real world" is where the string coupling is about unity and the volume of extra compact dimensions is about the same size as the string volume. Here we map the landscape of this "central" region in a model-independent way, assuming only that the string coupling and compact volume moduli are chiral superfields of N=1 supergravity in 4 dimensions, and requiring only widely accepted conditions: t...