14608251
Bounds on the mass and coupling constant of radion in the Randall–Sundrum theory
Abstract Assuming the Goldberger–Wise mechanism, we investigated the effective potential at the one-loop level in the Randall–Sundrum theory. We found the lower and upper bounds of the radion mass m φ and the radion-SM coupling constant, 0.8 GeV≲ m φ ≲260 GeV and 1400 GeV≲ Λ φ ≲1500 GeV for the one-loop level potential. These bounds were determined from two constraints of warp factor= O ( M W / M Pl ) and Higgs  vev ≃246 GeV, which can produce strong bounds of m φ and Λ φ . It is phenomenologically important that the one-loop allowed upper bound of the radion mass is about five times larger than the tree-level one, but the radion is still lighter than the Kaluza–Klein modes.
119501183
Muon anomalous magnetic moment, B --> X/s gamma and dark matter detection in the string models with dilaton domination
We consider the muon anomalous magnetic moment aµ in the string models with dilaton domination with two different string scales : the usual GUT scale and the intermediate scale. After imposing the direct search limits on the lightest neutral Higgs and SUSY particle masses and the lightest neutralino LSP, the a SUSY is predicted to be less than 65 (55) × 10 10 for Mstring = 2 × 10 16 GeV (3 × 10 11 GeV). If we further impose the B → Xs branching ratio, the predicted a SUSY becomes lower to 35 ×10 10 for intermediate string scale. The resulting LSP - proton scattering cross section is less than ∼ 10 7 pb, which is below the sensitivity of the current direct dark matter search experiments, but could be covered by future experiments.
14862395
Softness of brane-localized supersymmetry breaking on orbifolds
Abstract We consider the brane-localized supersymmetry breaking in 5D compactified on S 1 / Z 2 . In case of a bulk gaugino with arbitrary brane masses for its even and odd modes, we find the mass spectrum and the wave functions of gaugino. We show that the gaugino masses at the distant brane are soft in the usual sense in the effective field theory with zero modes of bulk gauge fields and they are also extremely soft in view of the one-loop finite mass of a brane scalar in the KK regularization.
16632385
Supersymmetric codimension-two branes and U(1)R mediation in 6D gauged supergravity
We construct a consistent supersymmetric action for brane chiral and vector multiplets in a six-dimensional chiral gauged supergravity. A nonzero brane tension can be accommodated by allowing for a brane-localized Fayet-Iliopoulos term proportional to the brane tension. When the brane chiral multiplet is charged under the bulk U(1)R, we obtain a nontrivial coupling to the extra component of the U(1)R gauge field strength and a singular scalar self-interaction term. Dimensionally reducing to 4D on a football supersymmetric solution, we discuss the implication of such interactions for obtaining the U(1)R D-term in the 4D effective supergravity. By assuming the bulk gaugino condensates and nonzero brane F- and/or D-term for the uplifting potential, we have all the moduli stabilized with a vanishing cosmological constant. The brane scalar with nonzero R charge then gets a soft mass of order the gravitino mass. The overall sign of the soft mass squared depends on the sign of the R charge as well as whether the brane F- or D-term dominates.
14019653
Top–bottom mass hierarchy, $s-\mu$ puzzle and gauge coupling unification with split multiplets
Abstract. Supersymmetric 5D SU(5) grand unification is considered. SU(5) is broken down to $G_{\mathrm{{SM}}}=SU(3)\times SU(2)\times U(1)$ by the $Z_2\times Z_2'$ assignment of the bulk field(s). The matter fields are located at the fixed point(s). In the bulk, a Higgs multiplet $\bar 5_H$ (containing the bottom doublet $H_1$) and the SU(5) gauge multiplet are located. At one fixed point, $H_2$ (the top doublet) and the standard model matter multiplets are presented. Because of the difference of the locations of $H_1$ and $H_2$, one can obtain a hierarchy between top and bottom Yukawa couplings. We also present a possible way to understand the s–$\mu$ mass puzzle in this framework of the split multiplet.
118458726
Gravity Mediation in 6d Brane‐World Supergravity
We consider the gravity‐mediated SUSY breaking within the effective theory of six‐dimensional brane‐world supergravity. We construct the supersymmetric bulk‐brane action by Noether method and find the nontrivial moduli coupling of the brane F‐ and D‐terms. We find that the low energy Kahler potential is not of sequestered form, so gravity mediation may occur at tree level. In moduli stabilization with anomaly effects included, the scalar soft mass squared can be positive at tree level and it can be comparable to the anomaly mediation.
16830627
U(1)R-mediated supersymmetry breaking from a six-dimensional flux compactification
We study the U(1)R-mediated supersymmetry breaking in a flux compactification of 6D chiral gauged supergravity with codimension-two branes. We consider a concrete model with manifest U(1)R invariance for moduli stabilization and visible sector in the context of 4D effective supergravity with gauged U(1)R and determine soft scalar masses in the visible sector mainly by a nonzero U(1)R D-term. We obtain a low energy superparticle spectrum and discuss on the implications of the obtained non-universal scalar soft masses on the SUSY phenomenology such as dark matter relic abundances.