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arXiv · 1609.06294

The Return of the King: No-Scale ${\cal F}$-$SU(5)$

Abstract

We revisit the viable parameter space in No-Scale ${\cal F}$-$SU(5)$, examining the Grand Unified Theory within the context of the prevailing gluino mass limits established by the LHC. The satisfaction of both the No-Scale boundary condition and the experimentally measured Standard Model (SM) like Higgs boson mass requires a lower limit on the gluino mass in the model space of about 1.9 TeV, which maybe not coincidentally is the current LHC supersymmetry search bound. This offers a plausible explanation as to why a supersymmetry signal has thus far not been observed at the LHC. On the contrary, since the vector-like flippon particles are relatively heavy due to the strict condition that the supersymmetry breaking soft term $B_μ$ must vanish at the unification scale, we also cannot address the recently vanished 750 GeV diphoton resonance at the 13 TeV LHC. Therefore, No-Scale ${\cal F}$-$SU(5)$ returns as a King after the spurious 750 GeV diphoton excess was gone with the wind.

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Tianjun Li, James A. Maxin, Dimitri V. Nanopoulos. 2016-09-20. The Return of the King: No-Scale ${\cal F}$-$SU(5)$. https://doi.org/10.1016/j.physletb.2016.11.022

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