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Jul 4 – 11, 2012
Melbourne Convention and Exhibition Centre
Australia/Melbourne timezone
ICHEP2012 - 36th International Conference for High Energy Physics

Should we still believe in constrained supersymmetry?

Jul 7, 2012, 6:00 PM
Melbourne Convention and Exhibition Centre

Melbourne Convention and Exhibition Centre

Melbourne Australia
Board: 13
Poster Sessions Track 2 - Beyond the Standard Model - SUSY Poster Session


Mr Benjamin Farmer (Monash University (AU))


We calculate Bayes factors to quantify how the feasibility of the constrained minimal supersymmetric model (CMSSM) has changed in the light of a series of observations. This is done in the subjective Bayesian spirit where probability reflects a degree of belief in a proposition and Bayes' theorem tells us how to update it after acquiring new information. Our experimental baseline is the approximate knowledge that was available before LEP, and our comparison model is the Standard Model with a simple dark matter candidate. To quantify the amount by which experiments have altered our relative belief in the CMSSM since the baseline data we compute the Bayes factors that arise from learning in sequence the LEP Higgs constraints, the XENON100 dark matter constraints, the 2011 1 $\text{fb}^{-1}$ LHC supersymmetry search results, and the early 2012 LHC Higgs search results. We find that LEP and the LHC strongly shatter our trust in the CMSSM (with $M_0$ and $M_{1/2}$ below 2 TeV), reducing its posterior odds by a factor of approximately three orders of magnitude. This reduction is largely due to the substantial Occam factors induced by the LEP and LHC Higgs searches and the poor maximum likelihood fit to the LHC Higgs search results.

Primary authors

Andy Buckley (University of Edinburgh (GB)) Mr Benjamin Farmer (Monash University (AU)) Csaba Balazs (Monash University) Martin John White (University of Melbourne (AU))

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