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The leading diagram that contributes to SUSY-breaking scalar masses in the models considered in this paper. The bulk line is a gaugino propagator with two mass insertions on the hidden brane.

The leading diagram that contributes to SUSY-breaking scalar masses in the models considered in this paper. The bulk line is a gaugino propagator with two mass insertions on the hidden brane.

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We consider supersymmetric theories where the standard-model quark and lepton fields are localized on a "3-brane" in extra dimensions, while the gauge and Higgs fields propagate in the bulk. If supersymmetry is broken on another 3-brane, supersymmetry breaking is communicated to gauge and Higgs fields by direct higher-dimension interactions, and to...

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... In par- ticular, the µ term can be generated by the Giudice-Masiero mechanism [10]. Other direct contact interactions between the hidden and visible sectors are suppressed be- cause of their spatial separation. The leading contribution to SUSY breaking for visible sector fields arises from loops of bulk gauge and Higgs fields, as illustrated in Fig. 1. These diagrams are ultraviolet convergent (and hence calculable) because the spatial separation of the hidden and visible branes acts as a physical point-splitting regulator. In effective field theory language, the contribution from loop momenta above the compactification scale is a (finite) matching contribution, while the con- ...
Context 2
... 5 compactified on a circle with circumference L ∼ 20/M, the exponential suppression is e −10 ∼ 5 × 10 −5 and Bµ/m 2 1/2 ∼ 4. As the number of extra dimensions increases, the strong coupling estimate is approached rapidly. See We now discuss the loop effects that communicate SUSY breaking to the visible sector fields, such as those illustrated in Fig. 1. These are ultraviolet convergent be- cause the separation of the hidden and visible branes acts as a physical point-splitting regulator for these diagrams. Another way to see this is that there is no local coun- terterm in the D-dimensional theory that can cancel a possible overall divergence. 5 Given a specific D-dimensional theory, ...

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... These flavor violating processes originate from soft SUSY breaking mass parameters which mixes different generations of sfermions. The dangerous flavor violating sfermion masses are avoided when the SUSY breaking masses are generated through gauge interactions and SM Yukawa interactions, leading us to gaugino mediation [10][11][12] or Higgs mediation [13,14]. 1 In these mediation mechanisms, the slepton and squark masses vanish at the tree-level and they are generated radiatively via gaugino loops or Higgs loops. Therefore, the flavor problem is absent within MSSM even if some SUSY particles are as light as O(0.1-1 TeV) [17]. ...
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... One can also consider other flavor-safe mediation mechanisms e.g. refs.[14][15][16][17][18]. ...
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A simple model for the explanation of the muon anomalous magnetic moment was proposed by the present authors within the context of the minimal supersymmetric standard model [1, 2]: Higgs-anomaly mediation. In the setup, squarks, sleptons, and gauginos are massless at tree-level, but the Higgs doublets get large negative soft supersymmetry (SUSY) breaking masses squared mHu2≃mHd2<0 at a certain energy scale, Minp. The sfermion masses are radiatively generated by anomaly mediation and Higgs-loop effects, and gaugino masses are solely determined by anomaly mediation. Consequently, the smuons and bino are light enough to explain the muon g − 2 anomaly while the third generation sfermions are heavy enough to explain the observed Higgs boson mass. The scenario avoids the SUSY flavor problem as well as various cosmological problems, and is consistent with the radiative electroweak symmetry breaking. In this paper, we show that, although the muon g − 2 explanation in originally proposed Higgs-anomaly mediation with Minp∼ 1016 GeV is slightly disfavored by the latest LHC data, the muon g − 2 can still be explained at 1σ level when Higgs mediation becomes important at the intermediate scale, Minp∼ 1012 GeV. The scenario predicts light SUSY particles that can be fully covered by the LHC and future collider experiments. We also provide a simple realization of mHu2≃mHd2<0 at the intermediate scale.
... A detail collider simulation is important but beyond the scope of the present paper. A smaller M inp would effectively lead to larger |µ|-term and thus larger muon g−2 (see (18)). To see this, let us fix the gravitino mass. ...
... One can also consider other flavor-safe mediation mechanisms e.g. Refs.[14][15][16][17][18].2 This kind of cosmological safety with alleviation of the gravitino problem with m 3/2 O(10) TeV can be found in the pure-gravity mediation scenario[19,20], minimal-split SUSY[21] or the split-SUSY[22,23].3 ...
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... Next, the strong constraint from stau instability motivates us to consider, in section 3, a model with gaugino+Higgs mediation, where there is a direct coupling of the Higgs doublets to the SUSY breaking field. Such a coupling is expected if the sequestered Kähler potential originates from an extra dimension and the Higgs doublets live in the bulk [26]. In this setup, the soft SUSY breaking masses for the Higgs doublets are assumed to be tachyonic, allowing hierarchical sfermion masses to be generated from Higgs loops without inducing too large FCNC [28][29][30]. ...
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A bstract We explore the possibility that the muon g − 2 anomaly and the nature of dark matter can be simultaneously explained within the framework of gaugino mediation, focusing on bino-like dark matter where the observed abundance is obtained via co-annihilations. The minimal model with non-universal gaugino masses is excluded by stau vacuum instability, although this constraint can be somewhat relaxed via the addition of a universal soft scalar mass (or B − L gaugino mediation). A more promising alternative is gaugino+Higgs mediation, which significantly raises the soft masses of the third generation sfermions leading to a split spectrum. In this framework, the muon g − 2 can be easily explained and the dark matter abundance obtained through either bino-wino or bino-slepton co-annihilations.