gaugemediated

Gaugemediated is an adjective used in particle physics to describe gauge-mediated supersymmetry breaking (GMSB) scenarios, in which the breaking of supersymmetry in a hidden sector is transmitted to the Minimal Supersymmetric Standard Model (MSSM) primarily through standard-model gauge interactions. In these models, a hidden sector with a SUSY-breaking F-term couples to messenger fields that carry Standard Model gauge charges. Through loop processes involving these messengers, gaugino masses arise at one loop and scalar soft masses arise at two loops, yielding a flavor-universal pattern of soft terms.

The typical setup includes a messenger sector with fields charged under SU(3)xSU(2)xU(1) and a messenger scale M_mess. The soft mass spectrum is governed by the SUSY-breaking scale F and the messenger content, with gaugino masses roughly proportional to (alpha_i/4π)(F/M_mess) and scalar masses set by two-loop contributions. A characteristic feature is that the gravitino is usually the lightest supersymmetric particle (LSP), while the next-to-lightest superpartner (NLSP) depends on the model and can be a neutralino, stau, or another sparticle. NLSP decays to gravitino can produce distinctive collider signatures and impose cosmological constraints.

Gaugemediated scenarios are valued for their relative flavor universality, reducing flavor-changing neutral current concerns compared with some other mediation schemes. They also face challenges, including the mu/B_mu problem, cosmological implications of a light gravitino, and model-building constraints to maintain gauge coupling unification. See also gauge mediation, supersymmetry, MSSM, messenger sector.