Mediation of Supersymmetry Breaking in Extra Dimensions

Abstract

We review the mechanisms of supersymmetry breaking mediation that occur in sequestered models, where the visible and the hidden sectors are separated by an extra dimension and communicate only via gravitational interactions. By locality, soft breaking terms are forbidden at the classical level and reliably computable within an effective field theory approach at the quantum level. We present a self-contained discussion of these radiative gravitational effects and the resulting pattern of soft masses, and give an overview of realistic model building based on this set-up. We consider both flat and warped extra dimensions, as well as the possibility that there be localized kinetic terms for the gravitational fields.

Large A t without the desert

“…Sequestered or brane to brane super-gravity mediation [39][40][41][42][43] overcomes many of these drawbacks: supersymmetry breaking effects are calculable and finite at one-loop. Mixing of Kähler potentials at tree level does not arise due to spatial separation of the visible and hidden sectors.…”

Large trilinearAtsoft supersymmetry breaking coupling from 5D MSSM

“…A sufficiently large trilinear A t soft supersymmetry breaking parameter allows us to reproduce the measured Higgs field mass of ∼ 125.5 GeV, while keeping a light stop superpartner (below ∼ 1 TeV) as preferred by the fine tuning argument for the Higgs mass. Realising such a high A t is usually difficult (in supergravity, mGMSB, ...) [8,9,10,11,18,19] but it is shown here concretely that 5D MSSM with compactification scale around 10-10 3 TeV can achieve large A t amounts at low scale (starting from A t (M GUT ) ∼ 0), thanks to the power law running and simultaneously with an approximate unification of the gauge couplings, the precision of this gauge unification is illustrated quantitatively (at one-loop) for various values of the compactification scale as pictured in Fig. 1.…”

The soft supersymmetry breaking in D=5 supergravity compactified on S_1/Z_2 orbifolds

“…The transmission is done via the exchange of bulk gravitational fields, notably the radion multiplet, which are the messengers of supersymmetry breaking in this scheme. The induced corrections, which are finite, have been calculated [22][23][24][25][26], and the resulting soft scalar masses on the visible brane were found to be tachyonic, although it has been clearly stated that a proper treatment of the radion multiplet may turn this picture yielding positive masses squared. In Ref.…”