119118937
Impacts of non-geometric moduli on effective theory of 5D supergravity
A bstract5D supergravity generically has moduli other than the radion that belong to 5D vector multiplets. We summarize the impacts of such non-geometric moduli on 4D effective theory of 5D supergravity on S1/Z2. We mainly discuss the structure of the effective Kähler potential including the one-loop quantum corrections. As an illustrative example, we construct a model in which the size of the extra dimension is stabilized at an exponentially large value compared to the Planck length, which is similar to the LARGE volume scenario in string theory.
119278125
SUSY flavor structure of generic 5D supergravity models
We perform a comprehensive and systematic analysis of the SUSY flavor structure of generic 5D supergravity models on S1/Z2 with multiple Z2-odd vector multiplets that generate multiple moduli. The SUSY flavor problem can be avoided due to contact terms in the 4D effective Kähler potential peculiar to the multi-moduli case. A detailed phenomenological analysis is provided based on an illustrative model.
119288533
Reheating processes after Starobinsky inflation in old-minimal supergravity
A bstractWe study reheating processes and its cosmological consequences in the Starobinsky model embedded in the old-minimal supergravity. First, we consider minimal coupling between the gravity and matter sectors in the higher curvature theory, and transform it to the equivalent standard supergravity coupled to additional matter superfields. We then discuss characteristic decay modes of the inflaton and the reheating temperature TR. Considering a simple model of supersymmetry breaking sector, we estimate gravitino abundance from inflaton decay, and obtain limits on the masses of gravitino and supersymmetry breaking field. We find TR ≃ 1.0 × 109 GeV and the allowed range of gravitino mass as 104 GeV ≲ m3/2 ≲ 105 GeV, assuming anomaly-induced decay into the gauge sector as the dominant decay channel.
119238697
Natural realization of a large extra dimension in 5D supersymmetric theory
An exponentially large extra dimension can be naturally realized by the Casimir energy and the gaugino condensation in 5D supersymmetric theory. The model does not require any hierarchies among the 5D parameters. The key ingredient is an additional modulus other than the radion, which generically exists in 5D supergravity. SUSY is broken at the vacuum, which can be regarded as the Scherk-Schwarz SUSY breaking. We also analyze the mass spectrum and discuss some phenomenological aspects.
119158878
Inflation in supergravity without Kähler potential
We propose a new class of inflation models in supergravity with higher derivative terms. In those models, the K\"ahler potential does not contain the inflaton multiplet, but a supersymmetric derivative term does. In the models, inflation is effectively driven by a single scalar field with a standard kinetic term and a scalar potential. Remarkably, the so-called $\eta$ problem does not exist in our models.
44450900
Illustrating SUSY breaking effects on various inflation mechanisms
A bstractWe consider the supersymmetry breaking effects on typical inflation models with different types of Kähler potential. The critical size of supersymmetry-breaking scale, above which the flatness of the inflaton potential is spoiled, drastically changes model by model. We present the universal description of such effects in terms of a field-dependent scaling factor by which gravity-mediated supersymmetry breaking terms are suppressed or enhanced, based on the conformal supergravity framework. Such a description would be useful when we estimate them in constructing supersymmetric models of particle cosmology.
15223689
QCD corrections to Higgs boson decays into squarks in the minimal supersymmetric standard model
Abstract We calculate the supersymmetric O ( α s ) QCD corrections to the widths of the Higgs boson decays H + → t b and H 0 , A 0 → t t , b b in the on-shell scheme within the Minimal Supersymmetric Standard Model. We find that the QCD corrections are significant, but that the squark pair decay modes are still dominant in a wide parameter region.
17784035
One-loop corrections to neutral Higgs boson decays into neutralinos
Abstract We present the one-loop corrected decay widths for the decays of the neutral Higgs bosons h 0 , H 0 and A 0 into a neutralino pair χ 0 m χ 0 n ( m , n =1,…,4) and to the decay χ 0 m →(h 0 ,H 0 ,A 0 )+ χ 0 n . The corrections contain the one-loop contributions of all fermions and sfermions. All parameters are taken on-shell. This requires a proper treatment of the neutralino mass and mixing matrix. The dependence on the SUSY parameters is discussed. The corrections can be large in certain regions of the parameter space.
7557738
PROBING THE NATURE OF COMPACTIFICATION WITH KALUZA-KLEIN EXCITATIONS AT THE LARGE HADRON COLLIDER
Abstract It is shown that the nature of compactification of extra dimensions in theories of large radius compactification can be explored in several processes at the Large Hadron Collider (LHC). Specifically it is shown that the characteristics of the Kaluza–Klein (KK) excitations encode information on the nature of compactification, i.e., on the number of compactified dimensions as well as on the type of compactification, e.g., of the specific orbifold compactification. The most dramatic signals arise from the interference pattern involving the exchange of the Standard Model spin 1 bosons ( γ and Z ) and their Kaluza–Klein modes in the dilepton final state pp → l + l − X . It is shown that LHC with 100 fb −1 of luminosity can discover Kaluza–Klein modes up to compactification scales of ≈6 TeV as well as identify the nature of compactification. Effects of the Kaluza–Klein excitations of the W boson and of the gluon are also studied. Exhibition of these phenomena is given for the case of one extra dimension and for the case of two extra dimensions with Z 2 × Z 2 , Z 3 , and Z 6 orbifold compactifications.
16568046
Higgs Particle Decays in Supersymmetry
We present a detailed study of the decays of the Higgs bosons H+, H0, and A0 within the Minimal Supersymmetric Standard Model including SUSY–QCD corrections. We find that the supersymmetric modes tb (tt, and for large tan β bb) can dominate the H+ (H0, A0) decays in a wide range of the model parameters due to the large Yukawa couplings and mixings of t and b. Compared to the conventional modes H+→τ+ντ, tb, and H0, A0→tt,bb, the supersymmetric modes can have an important impact on the Higgs boson searches at future colliders.
1388004
Low-scale anomalous U(1) and decoupling solution to supersymmetric flavor problem
Abstract Supersymmetric standard models where the ultraviolet cut-off scale is only a few orders of magnitude higher than the electroweak scale are considered. Phenomenological consequences of this class of models are expected to be very different from, for example, the conventional supergravity scenario. We apply this idea to a model with an anomalous U(1) gauge group and construct a viable model in which some difficulties of the decoupling solution to the supersymmetric flavor problem are ameliorated.