43 research outputs found
Solitonic supersymmetry restoration
Q-balls are a possible feature of any model with a conserved, global U(1)
symmetry and no massless, charged scalars. It is shown that for a broad class
of models of metastable supersymmetry breaking they are extremely influential
on the vacuum lifetime and make seemingly viable vacua catastrophically short
lived. A net charge asymmetry is not required as there is often a significant
range of parameter space where statistical fluctuations alone are sufficient.
This effect is examined for two supersymmetry breaking scenarios. It is found
that models of minimal gauge mediation (which necessarily have a messenger
number U(1)) undergo a rapid, supersymmetry restoring phase transition unless
the messenger mass is greater than 10^8 GeV. Similarly the ISS model, in the
context of direct mediation, quickly decays unless the perturbative
superpotential coupling is greater than the Standard Model gauge couplings.Comment: 17 pages, 3 figures, minor comments added, accepted for publication
in JHE
Thermal Evolution of the Non Supersymmetric Metastable Vacua in N=2 SU(2) SYM Softly Broken to N=1
It has been shown that four dimensional N=2 gauge theories, softly broken to
N=1 by a superpotential term, can accommodate metastable non-supersymmetric
vacua in their moduli space. We study the SU(2) theory at high temperatures in
order to determine whether a cooling universe settles in the metastable vacuum
at zero temperature. We show that the corrections to the free energy because of
the BPS dyons are such that may destroy the existence of the metastable vacuum
at high temperatures. Nevertheless we demonstrate the universe can settle in
the metastable vacuum, provided that the following two conditions are hold:
first the superpotential term is not arbitrarily small in comparison to the
strong coupling scale of the gauge theory, and second the metastable vacuum
lies in the strongly coupled region of the moduli space.Comment: 32 pages, 30 figure
Direct Mediation and Metastable Supersymmetry Breaking for SO(10)
We examine a metastable Macroscopic SO(N) SQCD model of
Intriligator, Seiberg and Shih (ISS). We introduce various baryon and meson
deformations, including multitrace operators and explore embedding an SO(10)
parent of the standard model into two weakly gauged flavour sectors. Direct
fundamental messengers and the symmetric pseudo-modulus messenger mediate SUSY
breaking to the MSSM. Gaugino and sfermion masses are computed and compared for
each deformation type. We also explore reducing the rank of the magnetic quark
matrix of the ISS model and find an additional fundamental messenger.Comment: 43 pages, Latex. Version to appear in JHEP
Tissue injury characterization by pre-contrast T1 mapping post myocardial infarction
Shah M Azarisman, Andrew Li, Dennis T Wong, James D Richardson, Seng Keong Chua, Luay Samaraie, Samuel L Sidharta, Timothy Glenie, Kerry Williams, Ben Koschade, Karen Teo, Matthew Worthley, Stephen G Worthle
Condensate cosmology in O'Raifeartaigh models
Flat directions charged under an R-symmetry are a generic feature of
O'Raifeartaigh models. Non-topological solitons associated with this symmetry,
R-balls, are likely to form through the fragmentation of a condensate, itself
created by soft terms induced during inflation. In gravity mediated SUSY
breaking R-balls decay to gravitinos, reheating the universe. For gauge
mediation R-balls can provide a good dark matter candidate. Alternatively they
can decay, either reheating or cooling the universe. Conserved R-symmetry
permits decay to gravitinos or gauginos, whereas spontaneously broken
R-symmetry results in decay to visible sector gauge bosons.Comment: 29 pages, 5 figures. Comments and references added, accepted for
publication in JHE
(De)Constructing a Natural and Flavorful Supersymmetric Standard Model
Using the framework of deconstruction, we construct simple, weakly-coupled
supersymmetric models that explain the Standard Model flavor hierarchy and
produce a flavorful soft spectrum compatible with precision limits. Electroweak
symmetry breaking is fully natural; the mu-term is dynamically generated with
no B mu-problem and the Higgs mass is easily raised above LEP limits without
reliance on large radiative corrections. These models possess the distinctive
spectrum of superpartners characteristic of "effective supersymmetry": the
third generation superpartners tend to be light, while the rest of the scalars
are heavy.Comment: 36 pages, 4 figures ; v2: references added, expanded discussion of
FCNC
Pseudomoduli Dark Matter and Quiver Gauge Theories
We investigate supersymmetric models for dark matter which is represented by
pseudomoduli in weakly coupled hidden sectors. We propose a scheme to add a
dark matter sector to quiver gauge theories with metastable supersymmetry
breaking. We discuss the embedding of such scheme in string theory and we
describe the dark matter sector in terms of D7 flavour branes. We explore the
phenomenology in various regions of the parameters.Comment: 24 pages, 12 figures, JHEP3.cl
Aspects of Non-minimal Gauge Mediation
A large class of non-minimal gauge mediation models, such as (semi-)direct
gauge mediation, predict a hierarchy between the masses of the supersymmetric
standard model gauginos and those of scalar particles. We perform a
comprehensive study of these non-minimal gauge mediation models, including mass
calculations in semi-direct gauge mediation, to illustrate these features, and
discuss the phenomenology of the models. We point out that the cosmological
gravitino problem places stringent constraints on mass splittings, when the
Bino is the NLSP. However, the GUT relation of the gaugino masses is broken
unlike the case of minimal gauge mediation, and an NLSP other than the Bino
(especially the gluino NLSP) becomes possible, relaxing the cosmological
constraints. We also discuss the collider signals of the models.Comment: 56 pages, 8 figures; v2:minor corrections, references added; v3:minor
correction
Optimal planimetry location for MRI-derived mitral inflow velocity assessment of diastolic function
Shah M Azarisman, Andrew Li, James D Richardson, Dennis T Wong, Seng Keong Chua, Michael Cursaro, Vince Schirripa, Kerry Williams, Ben Koschade, Mitra Shirazi, Julie Bradley, Karen Teo, Matthew Worthley, Stephen G Worthle