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Constraints on Supersymmetry using the latest data from cosmology, DM searches and LHC

Constraints on Supersymmetry using the latest data from cosmology, DM searches and LHC. C. Beskidt , W. de Boer, D. Kazakov, F. Ratnikov. Introduction to Supersymmetry (SUSY). Predictions of SM of particle physics in good agreement with experimental results

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Constraints on Supersymmetry using the latest data from cosmology, DM searches and LHC

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  1. Constraints on Supersymmetry using the latest data from cosmology, DM searches and LHC C. Beskidt, W. de Boer, D. Kazakov, F. Ratnikov

  2. Introduction to Supersymmetry (SUSY) Predictions of SM of particle physics in good agreement with experimental results BUT: still good arguments for physics beyond the SM No dark matter candidate, that can give the right amount of DM Quadratic divergences on the Higgs mass Higgs mechanism has to be introduced ad hoc Gravitation cannot be included within QFT etc. → need a theory beyond the SM Supersymmetry,…

  3. Introduction to SUSY SUSY = symmetry between fermions and bosons Minimal supersymmetric SM (MSSM): SM particles + SUSY partners + 2 Higgs Doublets (h,H,A,H±) SUSY leads to equal masses of superpartners → broken symmetry Soft Breaking would lead to over 100 free parameters → no prediction possible R Parity +1 R Parity -1

  4. Introduction to SUSY – Constrained MSSM Assuming unified SUSY masses and couplings at the GUT (~ 1016 GeV) scale → 4 free parameters and one free sign m0: common spin 0 mass m1/2: common spin ½ mass tanβ: ratio between the vev’s of the two Higgs fields A0: trilinear coupling sign(μ): sign of higgs mixing parameter Which combination of 4 free parameters are allowed?

  5. Outline Find allowed parameter space in CMSSM using a 2 method based on LHC SUSY searches, Higgs discovery, relic density, flavour constraints, electroweak constraints, direct DM searches Problem 1: Free CMSSM parameters are highly correlated Solution 1: Multi-step fitting approach → highly correlated parameters are fitted first for fixed other CMSSM parameters Problem 2: Higgs of 125 GeV and large  BR hard to accommodate in CMSSM Solution 2: go to NMSSM

  6. Constraints used for the 2-function Relic Density h2 = 0.1131 ± 0.0034 B → BRexp(B→) = (1.68 ± 0.31)·10-4 Myon g-2 Δa=(30.2 ± 6.3 ± 6.1) ·10-11 b →s BRexp(b→s) = (3.55 ± 0.24)·10-4 Bs→ BRexp(Bs→) < 4.5·10-9 Higgs Mass mh mh > 114.4 GeV LHC direct searches had < 0.001 – 0.03 pb XENON100 N < 1.8·10-45 - 6·10-45 cm2 Pseudo-scalar Higgs mA mA > 510 GeV for tanβ ~ 50 For more details see CB et al., EPJ C

  7. Combination of all constraints 2 = 2 – min2 For each 95% CL exclusion contour 2 = 5.99 LSP Best fit point χmin2 = 4.3 68% CL → Δχ2 < 2.3 Contour 1 2 3 4 5 LHC direct searches Bs→ mh > 114.4 GeV mA XENON100 95% CL → Δχ2 < 5.99 For more details see CB et al., EPJ C or backup slides

  8. Influence of g-2 Preferred region by g-2 if the errors are added quadratically or linearly g-2 gives a light preference for light SUSY masses but light SUSY masses are already excluded by the LHC direct searches → errors underestimated or additional loop contribution Deviation from SM 2-3: for heavy mSUSY

  9. (SM?) - Higgs found at the LHC Both the CMS and ATLAS experiment measured a Higgs within the errors of about 126 GeV What does this mean for the allowed CMSSM parameter space? CMS (CMS-PAS-HIG-12-020) ATLAS (ATLAS-CONF-2012-093) (125.3 ± 0.4 (stat) ± 0.5 (syst)) GeV (126.5 ± 0.6 (stat) ± 0.6 (syst)) GeV

  10. 125 GeV Higgs within the CMSSM A 125 GeV light Higgs is possible within the CMSSM if the SUSY masses are heavy enough and if the trilinear coupling A0 is negative The allowed parameter space is largely determined by the assigned error → strong dependence on the theoretical error Exp. ~ 2GeV, theo. ~ 3GeV, non-Gaussian → lin. addition → 5GeV (2=5.99) 95% C.L. contour Higgs mass contours 125 123 121 119 best fit points for different errors

  11. Summary so far 125 GeV Higgs hard to accomodate in CMSSM (unless one stretches the errors) In addition, couplings have tendency to deviate from SM (see next slides) Heavier Higgs and non-SM couplings easy to accomodate if mixing between Higgs doublet and additionally singlet, as proposed in NMSSM to solve -problem (Kim, Nilles Phys. Lett. B 138, 150 (1984))

  12. NMSSM versus MSSM NMSSM (Next to MSSM): Mixing: larger Higgs mass couplings to up and down type fermions can be different new free parameters: couplings ,  trilinear couplings A, A mixing parameter eff = <S> (in addition to m0, m1/2, A0, tan) MSSM NMSSM Higgs content 3 CP even 2 CP odd 1 singlet

  13. Fit to SM couplings (scale factors) CF = scale factor for coupling to fermions CV = scale factor for coupling to vector bosons Best fit point: CF ≈ 0.5 CV≈1.0 SM: CF = CV = 1 SM Best fit point (CMS-PAS-HIG-12-020)

  14. Higgs mass MSSM NMSSM: Mixing with singlet Hall, Pinner, Ruderman, arXiv 1112.2703 loop corrections Increases Higgs mass for large 

  15. Benchmark points in NMSSM Analyses have been done e.g. Ellwanger, Hugonie (arXiv:1203.5048 using GUT scale parameters), Mühlleitner et al. (arXiv:1201.2671 using low energy values of parameters) Benchmark points fulfill Higgs mass and couplings, but one needs very specific singlet mixing to obtain simultaneously mH=125 GeV, large branching into , small branching into  E.g. Benchmark points from Ellwanger, Hugonie, arXiv:1203.5048 Input at MSUSY Input at MGUT BM I BM II

  16. Typical Higgs masses and couplings Lightest Higgs H1 Second lightest Higgs H2 BM I II BM I II Strong mixing with singlet → R can be enchanced It is possible that 126 GeV is not the lightest Higgs

  17. Allowed region in -plane for BM I 2 including R and Mh constraint 2 including R, Mh and h2constraint Parameters strongly constrained by Mh=125, R=1.7, h2=0.11 (all other parameters fixed)

  18. Allowed region in m0m1/2-plane ex. by h2 excluded by R 2 including R, Mh and h2constraints. Parameters ,  and eff have been varied, A0, Aand A fixed  large allowed region within m0m1/2-plane

  19. Allowed region in m0m1/2-plane Even though other constraints have not been included to the previous fit, the result is in good agreement with b  s, Bs, B  and g-2 b  s  • Bs Similar to CMSSM: Including g-2 to 2 constant offset at large Msusy • g-2 B 

  20. Summary 125 GeV Higgs within CMSSM only possible for high SUSY masses Allowed CMSSM parameter space depends on total error of the Higgs mass Within NMSSM one can get a 125 GeV Higgs and in addition an enhancement/reduction in Rγγ/ττ“naturally” because of large mixing with additional Higgs singlet Other constraints fulfilled like in CMSSM, e.g. h2 ,b →s, Bs→, B →, and g-2 → good starting point to do same minimization as in CMSSM → work in progress…

  21. BACKUP

  22. Details on χ2-function Relic Density B →τν Myon g-2 b →sγ Bs→μμ BRexp(Bs→μμ) < 4.5·10-9 Higgs Mass mh mh > 114.4 GeV LHC direct searches σhad < 0.003 – 0.03 pb DDMS σχN < 8·10-45 - 2·10-44 cm2 Pseudo-scalar Higgs mA mA > 480 GeV for tanβ ~ 50 Experimental Values Defined in a straight forward way:

  23. Details on χ2-function? Relic Density Ωh2 = 0.1131 ± 0.0034 B →τν BRexp(B→τν) = (1.68 ± 0.31)·10-4 Myon g-2 Δaμ=(30.2 ± 6.3 ± 6.1) ·10-11 b →sγ BRexp(b→sγ) = (3.55 ± 0.24)·10-4 Bs→μμ Higgs Mass mh LHC direct searches σhad < 0.003 – 0.03 pb DDMS σχN < 8·10-45 - 2·10-44 cm2 Pseudo-scalar Higgs mA mA > 480 GeV for tanβ ~ 50 95% CLonly added if XSUSY > X95% XSUSY = model value of BR(Bs→μμ) or mh X95% can be determined from requirement Δχ2=5.99 at 95% CL exclusion limit

  24. Details on χ2-function? Relic Density Ωh2 = 0.1131 ± 0.0034 B →τν BRexp(B→τν) = (1.68 ± 0.31)·10-4 Myon g-2 Δaμ=(30.2 ± 6.3 ± 6.1) ·10-11 b →sγ BRexp(b→sγ) = (3.55 ± 0.24)·10-4 Bs→μμBRexp(Bs→μμ) < 4.5·10-9 Higgs Mass mh mh > 114.4 GeV LHC direct searches DDMS Pseudo-scalar Higgs mA 95% CL exclusion contours Defineχ2=(XSUSY - X95%)2/σ95%2 XSUSY = model value of mA or hadronic cross section or χN elastic scattering cross section σ95% can be determined from 1σ band given by experiments X95% determined from requirement Δχ2=5.99 at 95% CL exclusion contour

  25. Typical Sparticle masses and LSP mixing (NMSSM) BM I II BM I II

  26. Start with Relic Density Constraint Problem:for excluded first diagram too small. Last diagram also small → can get correct relic density by mA s-channel annihilation mA can be tuned with tanβ for any m1/2→ tanβ≈ 50 (see next slide)

  27. Relic Density Constraint – Dependence on tanβ tan  50 Co-annihilation (Tree Level) m1 running m2 running running < 0 → if ht and hb similar → small mAfor tan= mt/mb  50 Fit of Ωh2determines mA and tanβ mAm1/2 arXiv:1008.2150

  28. What about Higgs mA limit? tanβ≈ 50 (CMS PAS HIG-11-009) Atlas similar For tanβ≈ 50 mA > 440 GeV

  29. Examples for high correlation χ2 for Bs →μμ and Ωh2 Both strongly dependent on tanβ Bs →μμ Ωh2 Origin of correlation: For given m0 only very specific values of tan For given tan only very specific values of A0 focus point region mA exchange co-annihilation region

  30. Origin of correlation exp. Value Ωh2 Upper Limit for Bs→ μμ(LHCb, CMS) A0=0 Upper limit for tanβ for upper limit on Bs →μμ Best tanβ for Ωh2

  31. Origin of correlation exp. Value Ωh2 Upper Limit for Bs→ μμ A0=1580 GeV Common tanβ can only be found for specific A0 value Best tanβ for Bs→ μμ and Ωh2 simultaneously

  32. Reason for strong A0 dependence of Bs→ μμ arXiv:hep-ph/0203069v2 Becomes small, if can be achieved by adjusting At, till mixing term ~ (At – μ/tanβ) becomes small. Important only for light SUSY masses (see blue region) Stop mass difference

  33. Combination of Bs → μμ and Ωh2 Tension at large tan from Bs   can be removed by large A0 Tension can’t be removed by varying A0  because A0 < 3m0, A0 not high enough to get small BR Tension still there although A0 large enough to get small BR

  34. Why there‘s still a tension for large m0? Bs →μμ smaller than SM value, even at large tanβ Bs →μμ needs large A0 for large tanβ Ωh2 too high for large A0 m0=1000 m1/2=250 SM value mA high → small cross section Small Stau mass contribute to Ωh2

  35. How to treat theoretical errors? Theoretical errors can be treated as nuisance parameters and integrated over in the probability distribution (=convolution for symm. distr.) If errors Gaussian, this corresponds to adding the experimental and theoretical errors in quadrature Assume σtheo ~ σexp (only then important) Convolution of Gaussian + “flat top Gaussian” (expected if theory errors indicate a range) Convolution of 2 Gaussians Adding errors linearly more conservative approach for theory errors.

  36. SUSY particles can be produced in pp collisions at the LHC Combination of the different cross sections of Direct searches for SUSY particles Parametrization of with σeff2 that Δχ2 = χ2 – χ2min = 5,99 95% CL exclusion by CMS + Atlas (Jets+MET) CMS PAS SUS-11-003 arXiv:1109.6572 Contribution to σtot=0,1pb

  37. Direct search for dark matter (DDMS) Assume Neutralino is LSP and therefore perfect WIMP candidate Direct detection of WIMPs through elastic scattering on heavy nuclei Coherent scattering: σ ~ N2 and effective coupling on proton/neutron fp/fn Effective coupling includes couplings of WIMPs on quarks fqn/fqp 90% CL →Δχ2 = 4,21 (arXiv:1005.0380)

  38. Including DDMS constraint into χ2 Uncertainties Local DM density (0,3/1,3 GeV/cm³) Effective coupling (especially s-quark) because of different calculations lattice πN conservative

  39. Excluded parameter space by XENON100 Scattering cross section is proportional to the product of gaugino und higgsino component → Increase of the cross section if higgsino component is increasing Higgsino component increases for high values of m0→ DDMS is sensitive for high m0 in contrast to the direct searches at the LHC

  40. Comparison to other groups Strong correlation between A0 and tanβ Buchmueller et al. arXiv: 1110.3568 If one include the exclusion limit of the LHC, the difference between the 95% CL contour of the quadratic and linear addition of the errors vanishes.

  41. Exclusion because of Ωh2 for large values of m1/2 Excluded region for large values of m1/2 and small m0 because of the relic density For this combination of m0 and m1/2 one needs a high value of tanβ for the correct relic density For such high values of tanβ the Neutralino is not the LSP anymore Χ2 contribution of Ωh2 m0=500 GeV m1/2=1300 GeV LSP

  42. Contributors to CF and CV

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