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High Energy


Joint Theory Seminar: Takemich Okui

Description Joint Theory Seminar
Speaker: Takemichi Okui (FSU)
Host: Spencer Chang
Room: 432 PHY
Title: Flavorful Gravity Mediation
Abstract: We present a complete, viable model of gravity-mediated supersymmetry breaking that is safe from all flavor constraints. The central new idea is to employ a supersymmetry breaking sector without singlets, but with D-terms comparable to F-terms, causing supersymmetry breaking to be dominantly communicated through \UR-symmetric operators. We construct a visible sector that is an extension of the MSSM where an accidental \UR-symmetry emerges naturally. Gauginos acquire Dirac masses from gravity-mediated D-terms, and tiny Majorana masses from anomaly-mediated contributions. Contributions to soft breaking scalar (mass)2 arise from flavor-arbitrary gravity-induced F-terms plus one-loop finite flavor-blind contributions from Dirac gaugino masses. Renormalization group evolution of the gluino causes it to naturally increase nearly an order of magnitude larger than the squark masses. This hierarchy, combined with an accidentially \UR-symmetric visible sector, nearly eliminates all flavor violation constraints on the model. If we also freely tune couplings and phases within the modest range 0.1-1, while maintaining nearly flavor-anarchic Planck-suppression contributions, we find our model to be safe from DmK, eK, and m\ra e lepton flavor violation. Dangerous \UR-violating <html>K&#228;hler</html> operators in the Higgs sector are eliminated through a new gauged \UX symmetry that is spontaneously broken with electroweak symmetry breaking. Kinetic mixing between \UX and \UY is present with loop-suppressed (but log-enhanced) size e. The Z associated with this \UX has very peculiar couplings - it has order one strength to Higgs doublets and approximately e strength to hypercharge. The Z could be remarkably light and yet have escaped direct and indirect detection.
Date Mon, May 10, 2010
Time 6:30am-7:30am PDT
Duration 1 hour
Access Public
Created by High-Energy Seminars
Updated Fri, October 26, 2012 9:54am PDT

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