3–7 Dec 2012
IST Congress Center
Europe/Lisbon timezone
<big>NEWS: Deadline for Proceedings - 28 February 2013 </big>

Likelihood and Naturalness of SUSY models after the Higgs discovery.

5 Dec 2012, 14:30
45m
Main Auditorium (IST Congress Center)

Main Auditorium

IST Congress Center

Instituto Superior Técnico Avenida Rovisco Pais,1 1049-001 Lisboa, Portugal

Speaker

Dr D Ghilencea (NIPNE Bucharest and CERN)

Description

I provide a comparative study of the likelihood and naturalness of the most popular SUSY models, consistent with recent LHC results for the Higgs. I show that if one regards the EW minimum conditions as constraints that fix the EW scale, the (constrained) likelihood of such models to fit the EW data is changed and is actually smaller (worse) than usually thought, being equal to the ratio L/Delta of the usual likelihood L and the traditional fine tuning measure ("in quadrature") Delta of the EW scale. Equivalently chi^2 receives a correction, so far ignored: chi^2_new=chi^2_old+2*Log[Delta]. As a result a large likelihood (or min chi^2/d.o.f.) actually demands a large ratio L/Delta, from which a model-independent bound is derived for the EW scale fine-tuning: Delta<<exp(d.o.f./2). Current SUSY models: CMSSM, NUHM1, NUHM2, NMSSM, MSSM with non-universal gaugino masses, are examined from this point of view for a Higgs mass near 126GeV, with conclusions for their viability. (d.o.f.=number of degrees of freedom). Based on: http://arxiv.org/abs/arXiv:1208.0837, http://arxiv.org/abs/arXiv:1203.0569.

Primary author

Dr D Ghilencea (NIPNE Bucharest and CERN)

Presentation materials