SUSY models under siege: LHC constraints and electroweak fine-tuning

Understand

Recent null results from LHC8 SUSY searches along with the discovery of a SM-like Higgs boson with mass m(h) ~ 125.5 GeV indicates sparticle masses in the TeV range, causing tension with conventional measures of electroweak fine-tuning.

• We propose a simple Fine-tuning Rule which should be followed under any credible evaluation of fine-tuning.
• We believe that overestimates of electroweak fine-tuning by conventional measures all arise from violations of this rule.
• We show that to gain accord with the Fine-tuning Rule, then both Higgs mass and the traditional \Delta_{BG} fine-tuning measures reduce to the model-independent electroweak fine-tuning measure \Delta_{EW}.