75 research outputs found
Supersymmetry breaking and gauge mediation in models with a generic superpotential
We present a general scheme for finding or creating a metastable vacuum in
supersymmetric theories. By using the formalism, we show that there is a
parameter region where a metastable vacuum exists in the Wess-Zumino model
coupled to messenger fields. This model serves as a perturbative renormalizable
model of direct gauge mediation.Comment: 13 pages, 1 figures. v2 two loop corrections and references added. to
appear in PL
Radiation of Supersymmetric Particles from Aharonov-Bohm R-string
We study radiation of supersymmetric particles from an Aharonov-Bohm string
associated with a discrete R-symmetry. Radiation of the lightest supersymmetric
particle, when combined with the observed dark matter density, imposes
constraints on the string tension or the freeze-out temperature of the
particle. We also calculate the amplitude for Aharonov-Bohm radiation of
massive spin particles.Comment: 18 pages, 2 figures, v2: typos corrected,v3: section 3.2 and appendix
B adde
Gravitational Correction to Fuzzy String in Metastable Brane Configuration
We study dynamics of a cosmic string in a metastable brane configuration in
Type IIA string theory. We first discuss a decay process of the cosmic string
via a fuzzy brane (equivalently bubble/string bound state) by neglecting
gravitational corrections in ten-dimension. We find that depending on the
strength of the magnetic field induced on the bubble, the decay rate can be
either larger or smaller than that of symmetric bubble. Then, we
investigate gravitational corrections to the fuzzy brane by using the extremal
black -five brane solution, which makes the lifetime of the metastable
state longer.Comment: 21 pages, 9 figure
Light Gauginos and Conformal Sequestering
In a wide class of direct and semi-direct gauge mediation models, it has been
observed that the gaugino masses vanish at leading order. It implies that there
is a hierarchy between the gaugino and sfermion masses, invoking a fine-tuning
problem in the Higgs sector via radiative corrections. In this paper, we
explore the possibility of solving this anomalously light gaugino problem
exploiting strong conformal dynamics in the hidden sector. With a mild
assumption on the anomalous dimensions of the hidden sector operators, we show
that the next to leading order contributions to the gaugino masses can
naturally be in the same order as the sfermion masses. \mu/B_\mu problem is
also discussed.Comment: 17 pages, 1 figure. References adde
Supersymmetry Breaking and Gauge Mediation
We review recent works on supersymmetry breaking and gauge mediation. We
survey our current understanding of dynamical supersymmetry breaking mechanisms
and describe new model building tools using duality, meta-stability, and
stringy construction. We discuss phenomenological constraints and their
solutions, paying attentions to issues with gaugino masses and electroweak
symmetry breaking.Comment: 42 pages, 9 figures, invited review to appear in Annu. Rev. Nucl.
Part. Sci. v2: references adde
Baryon as Impurity for Phase Transition in String Landscape
We consider a decay of a false vacuum in flux compactifications of type IIB
string theory and study a catalytic effect for a phase transition induced by a
new type of impurities. We concentrate on the large N dual of a
D5-brane/anti-D5-brane system which has a rich vacuum structure. We show that
D3-branes wrapping the 3-cycles can form a dibaryon and make a bound state with
a monopole. We find that these baryon-like objects can make the lifetime of the
metastable vacuum shorter.Comment: 22 pages, 13 figure
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