Abstract
We show that in gauge mediation models where heavy messenger masses are provided by the adjoint Higgs field of an underlying SU ( 5 ) theory, a generalized gauge mediation spectrum arises with the characteristic feature of having a neutralino LSP much lighter than in the standard gauge or gravity mediation schemes. This naturally fits in a hybrid scenario where gravity mediation, while subdominant with respect to gauge mediation, provides μ and Bμ parameters of the appropriate size for electroweak symmetry breaking.
Highlights
Introduction and motivationsSupersymmetry (SUSY) breaking is the central open question in supersymmetric extensions of the Standard Model
- gravity mediation [1] generates all soft terms needed at low energy in the Minimal Supersymmetric Standard Model (MSSM), including the μ and Bμ terms of the Higgs sector [2], all being of the order of the gravitino mass at high energy
We have shown that models in which supersymmetry breaking is predominantly transmitted by gauge interactions lead to a light neutralino if the messenger mass matrix is oriented with the hypercharge generator, M ∼ vY
Summary
Supersymmetry (SUSY) breaking is the central open question in supersymmetric extensions of the Standard Model. An obvious way of combining the advantages and possibly reducing the disadvantages of both mechanisms is to assume m3/2 ∼ (0.01 − 0.1) MGM , MGM ∼ 1 TeV In this case, the FCNC amplitudes induced by the non-universal gravity contributions to soft scalar masses are suppressed by a factor of order m23/2/MG2 M. Since the gaugino masses Ma (where a refers to the SM gauge group factor Ga = SU(3)C, SU(2)L or U(1)Y ) are proportional to Tr (Q2a/M), where the Qa’s stand for the charges of the messenger fields under Ga, it is readily seen that the gauge-mediated contribution to the bino mass vanishes in the limit X0 = 0: M1|GMSB, X0=0 ∝ Tr Y 2M −1 ∝ Tr Y = 0. The appendices contain technical details about the computation of the MSSM soft terms and the quantum corrections to the scalar potential
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
