Tuesday, June 5, 2012

1206.0264 (Andrew Fowlie et al.)

The CMSSM Favoring New Territories: The Impact of New LHC Limits and a
125 GeV Higgs
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Andrew Fowlie, Malgorzata Kazana, Kamila Kowalska, Shoaib Munir, Leszek Roszkowski, Enrico Maria Sessolo, Sebastian Trojanowski, Yue-Lin Sming Tsai
We present an updated and extended global analysis of the Constrained MSSM (CMSSM) taking into account new limits on supersymmetry from ~5/fb datasets at the LHC. In particular, in the case of the razor limit by the CMS Collaboration we simulate detector efficiency for the experimental analysis and derive an approximate but accurate likelihood function. We also discuss the impact of a possible Higgs boson with mass near 125 GeV, as suggested by recent data, and of a new improved limit on B_s -> \mu^+\mu^- on the global fit. We identify high credible posterior probability regions of the CMSSM parameters as the stau-coannihilation and the A-resonance funnel region, whose importance is now much larger, while we find that the focus point region is now disfavored. As for the Higgs, we find that, after taking into account both theoretical and experimental uncertainties on its mass, the impact of the possible Higgs mass near 125 GeV on Bayesian inferences is actually fairly limited. We also find that relatively minor and somewhat arbitrary assumptions in parameterizing LHC lower mass limits and the Higgs boson mass can induce a large shift in the location of the best-fit point. This puts into question the robustness of the usual chi-square approach. We discuss the goodness-of-fit and find that, while it is difficult to calculate a p-value, the g-2 constraint makes the overall fit of the CMSSM nevertheless poor. Thus, we also consider a scan without this constraint, and we allow \mu\ to be either positive or negative. We find that the global fit improves enormously for both signs of \mu, with a slight preference for \mu<0.
View original: http://arxiv.org/abs/1206.0264

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