1 / 21

Prediction of Supersymmetric Spectra in the CMSSM and NUHM1 with Frequentist Analysis

Prediction of Supersymmetric Spectra in the CMSSM and NUHM1 with Frequentist Analysis. Henning Flaecher CERN. in collaboration with: O. Buchmueller , R. Cavanaugh, A. De Roeck , J. Ellis, S. Heinemeyer , G. Isidori , K. Olive, P. Paradisi , F. Ronga , G. Weiglein. Introduction.

asher-lyons
Télécharger la présentation

Prediction of Supersymmetric Spectra in the CMSSM and NUHM1 with Frequentist Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Prediction of Supersymmetric Spectra in the CMSSM and NUHM1 with Frequentist Analysis Henning Flaecher CERN in collaboration with: O. Buchmueller, R. Cavanaugh, A. De Roeck, J. Ellis, S. Heinemeyer, G. Isidori, K. Olive, P. Paradisi, F. Ronga, G. Weiglein

  2. Introduction • How can we best exploit the available experimental data to constrain New Physics models? • Combine as much experimental information as possible • Famous example: • Standard Model fit to electroweak precision data • Extend it to include physics beyond the Standard Model • Here: Minimal SuperSymmetic Standard Model (MSSM) • Necessary tools: • calculations for experimental observables in that model and • a common framework that interfaces between the different calculations and combines the obtained information • Objectives/Outcome: • Fit model parameters in some MSSM scenarios • Explore sensitivity of different observables to parameter space SUSY09, Boston

  3. Constraining MSSM parameter space • What observables can be used to constrain the model? • Low energy (precision) data • Flavour physics (many constraints from B physics) • Other low energy observables, e.g. g-2 • High energy (precision) data • Precision electroweak observables, e.g. MW, mtop, asymmetries • Cosmology and Astroparticle data • e.g. relic density • How to exploit this information? • State of the art theoretical predictions (tools) • Development of a framework for combination of these tools • Collaboration between experiment and theory See O. Buchmüller et al., PLB 657/1-3 pp.87-94 and JHEP 0809:117,2008 SUSY09, Boston

  4. Common framework development • General overview: • Consistency • Relies on SLHA interface • Modularity • Compare calculations • Add/remove predictions • State-of-the-art calculations • Direct use of code from experts SUSY09, Boston

  5. Common framework applications • Use case: • Fit today’s data (2-minimisation) • Constrain SUSY parameter space • Will become even more interesting when combined with discoveries • Various modes: • Overall best minimum (MINUIT) • 2 scans • Markov-Chain Monte Carlo for parameter space sampling SUSY09, Boston

  6. List of implemented observables SUSY09, Boston

  7. Example Application • Constraining the parameter space of theCMSSM • multi-parameter 2 “fit” See O. Buchmüller et al. PLB 657/1-3 pp.87-94 Non Universal Higgs Model1: one extra free parameter scalar contributions to Higgs masses at GUT scale allowed to differ from those to squark and slepton masses SUSY09, Boston

  8. CMSSM • Sampling of parameter space with Markov-Chain Monte Carlo type technique • Full sampling of parameter space (~25M points) • only observe 1 minimum at M0 ~ 70 GeV, M1/2 ~ 320 GeV • No preference for Focus Point region results still preliminary Δχ2 M0 Best fit point: M0 = 65 GeV M1/2 = 320 GeV A0 = 113 GeV tanβ= 11.2 M1/2 SUSY09, Boston

  9. Prospects for finding CMSSM at LHC “LHC Weather Forecast” JHEP 0809:117,2008 O.Buchmueller, R.Cavanaugh, A.De Roeck,J.R.Ellis, H.F., S.Heinemeyer,G.Isidori, K.A.Olive, P.Paradisi, F.J.Ronga, G.Weiglein Simultaneous fit of CMSSM parameters m0, m1/2, A0, tan (>0) to more than 30 collider and cosmology data (e.g. MW, Mtop, g-2, BR(BX), relic density) “CMSSM fit clearly favors low-mass SUSY – A signal might show up very early?!” SUSY09, Boston

  10. Particle Masses: CMSSM • Extensive sampling allows to take a look at particle spectra • LEP Higgs constraint not included • M1/2 controls gluino, chargino, neutralino masses • also for squarks (M0 < M1/2) • Favouredgluino mass around 650 GeV • Lightest squark around 500 GeV Δχ2 χ1+ χ10 bsγ g-2 (disfavours large m12) Δχ2 ~ g ~ preliminary t1 SUSY09, Boston

  11. Particle Masses: CMSSM • Extensive sampling allows to take a look at particle spectra • LEP Higgs constraint not included • M1/2 controls gluino, chargino, neutralino masses • also for squarks (M0 < M12) • Favouredgluino mass around 650 GeV • Lightest squark around 500 GeV Δχ2 χ1+ χ10 with LEP Higgs constraint Δχ2 ~ g ~ preliminary t1 SUSY09, Boston

  12. NUHM1 • Work in progress • preliminary sampling of parameter space • 25M points • up to tanβ≤ 45 • Observe clear minimum structure • again, only one minimum results still preliminary M0 Best fit point: M0 = 170 GeV M1/2 = 260 GeV A0 = -1330 GeV tanβ= 12.2 mH2 = -1313044 GeV2 M1/2 SUSY09, Boston

  13. What about beyond CMSSM? – NUHM1 “LHC Weather Forecast” JHEP 0809:117,2008 O.Buchmueller, R.Cavanaugh, A.De Roeck,J.R.Ellis, H.F., S.Heinemeyer,G.Isidori, K.A.Olive, P.Paradisi, F.J.Ronga, G.Weiglein Non Universal Higgs Model1: - one extra free parameter scalar contributions to Higgs masses at GUT scale allowed to differ from those to squark and slepton masses NUHM1 Simultaneous fit of NUHM1 parameters m0, m1/2, A0, tan, mH2 and  to more than 30 collider and cosmology data (e.g. MW, Mtop, g-2, BR(BX), relic density) NUHM1 fit also favours low-mass SUSY SUSY09, Boston

  14. Particle Masses: NUHM1 • Non Universal Higgs Model1: • Minima at similar masses as in CMSSM • well within LHC reach • not as tightly constrained towards higher masses Δχ2 χ10 χ1+ χ10 Δχ2 ~ g ~ ~ g t1 preliminary SUSY09, Boston

  15. Lightest Higgs Constraint • Likelihood profile for lightest Higgs mass • CMSSM: Lightest Higgs just below LEP bound but much tighter constrained than SM Higgs • NUHM1: preferred Higgs mass at ~120 GeV naturally above LEP limit but less constrained towards lower masses CMSSM NUHM1 SUSY09, Boston

  16. Dark Matter Constraints: CMSSM • Comparison of direct searches with collider searches pSI: spin-independent dark matter - WIMP elastic scattering cross section on a free proton. with without Higgs constraint preliminary Example how combination of direct and indirect measurements can provide information about validity of specific new physics models SUSY09, Boston

  17. Dark Matter constraint: NUHM1 • Cross-section and mass not quite as well constrained pSI: spin-independent dark matter - WIMP elastic scattering cross section on a free proton. χ10 preliminary σpSI SUSY09, Boston

  18. CMSSM vs NUHM1 • Limits on neutralino mass once real data is available • exploit correlation between neutralino mass and M1/2 • Discovery/Exclusion in M1/2 can be translated into neutralino mass reach NUHM1 NUHM1 CMSSM SUSY09, Boston

  19. Conclusions • For comprehensive interpretation of LHC data it is necessary to check for consistency with all available experimental data • Efforts to combine… • various sets of experimental constraints • in different models • and in different ways …are ongoing • Investigate simple models: • CMSSM: provides Higgs mass compatible with LEP limit but much better constraint • would be discoverable at the early stages of the LHC (1fb-1) • NUHM1: preferred Higgs value above LEP limit but less constrained towards lower value • Early LHC data will probe these models! SUSY09, Boston

  20. BACKUP SUSY09, Boston

  21. Omega CMSSM: Prediction for Omega h2 from all other constraints SUSY09, Boston

More Related