SUSY and Exotics. UK HEP Forum"From the Tevatron to the LHC, Cosener s House, May /05/2009 Steve King, UK HEP Forum '09, Abingdon 1

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SUSY and Exotics Standard Model and the Origin of Mass Puzzles of Standard Model and Cosmology Bottom-up and top-down motivation Extra dimensions Supersymmetry

1 SUSY and Exotics Standard Model and the Origin of Mass Puzzles of Standard Model and Cosmology Bottom-up and top-down motivation Extra dimensions Supersymmetry - MSSM -NMSSM -E 6 SSM and its exotics UK HEP Forum"From the Tevatron to the LHC, Cosener s House, May /05/2009 Steve King, UK HEP Forum '09, Abingdon 1

2 Origin of mass in SM H 2 λ V = m H + H Tree-level min cond m = λv = λ GeV 2 2 H m + δm = λ 246GeV Including rad corr 2 2 ( ) 2 H H ( 246 ) 2 H Q 3L H t R Λ δ mh( top loop) = G Λ = ( 100 ) 2 Fmt GeV 2π 1TeV Fine-tuning is required if the cut-off Λ 1TeV Hierarchy problem new physics at Λ TeV 2 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 2

3 Standard Model Puzzles 1. The origin of mass - the origin of the weak scale, its stability under radiative corrections, and the solution to the hierarchy problem (most urgent problem of LHC) 2. The quest for unification - the question of whether the three known forces of the standard model may be related into a grand unified theory, and whether such a theory could also include a unification with gravity. 3. The problem of flavour - the problem of the undetermined fermion masses and mixing angles (including neutrino masses and mixing angles) together with the CP violating phases, in conjunction with the observed smallness of flavour changing neutral currents and very small strong CP violation. 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 3

4 Cosmology provide further motivation for new physics BSM: Origin of dark energy? Origin of dark matter? Origin of atoms? Origin of the Universe? 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 4

5 Hierarchy problem provides a bottom-up motivation for new physics BSM Technicolour Supersymmetry TeV Extra dimensions Mz The Hierarchy Problem 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 5

6 String Unification provides a top-down motivation for new physics BSM String Unification M* Supersymmetry Extra dimensions New TeV scale physics 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 6

7 Extra dimensions Typical string/d-brane set-up involves extra dimensions An entomological analogy bulk Antoniadis brane 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 7

8 UED: flat extra dimensions with everything in the bulk gives KK excitations of everything LKP stable WIMP Cheng, Matchev,Schmaltz 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 8

9 RS: warped extra dimensions with gravity only in the bulk. 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 9

10 Supersymmetry FERMIONS BOSONS BOSONS FERMIONS 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 10

11 What has SUSY ever done for us? Solve hierarchy problem (origin of mass) Facilitates unification (quest for unification) Provides WIMPs (origin of dark matter) Helps inflation (origin of universe) Enables baryogenesis (origin of atoms) What SUSY doesn t t help with: Cosmological constant (origin of dark energy) Quark and lepton spectrum (flavour problem) In fact SUSY makes the flavour problem worse due to squarks and sleptons (sflavour problem) 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 11

12 Stabilising the Hierarchy in SUSY δm δm 3 ( top) = λ Λ 8π H 2 t 3 ( stop) = + λ Λ 8π H 2 t Cancel Quadratic divergence cancels leaving δm 9 8π λ m H 2 t t SUSY stabilises the hierarchy providing m < 1 t TeV ln Λ m t 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 12

13 MSSM sparticle spectra for various mediation mechanisms 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 13

14 MSSM EWSB W = μhuhd H u + 0 H u Hd 0 Hd Hu Hd = = A nice feature of MSSM is radiative EWSB Ibanez-Ross 2 (s)top loops drive negative 0 M Z m 2 2 H u + μ M 2 Min conds at low energy Z ( μ + m + δ ) H mh 2 M GUT u H u Q 3L t R m Hu 3 M δm λ m ln ~ O(1) m u 4π Q GUT 2 H 2 t stop stop H Naturalness requirement is M Z δm Hu m stop But M Z m stop Two per cent fine tuning Also no reason why μ 1 TeV (μ problem) Motivates non-minimal SUSY models 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 14

15 Non-Minimal SUSY Models To solve the μ problem and reduce fine tuning consider: W= λsh u H d where singlet <S> μ But leads to weak scale axion due to global U(1) PQ symmetry Need to remove axion somehow In NMSSM we add S 3 to break U(1) PQ to Z 3 but this results in cosmological domain walls (or tadpoles if broken) In E 6 SSM we gauge the U(1) PQ symmetry to eat the axion resulting in a massive Z gauge boson. Anomalies are cancelled by three complete 27 s of E 6 at the TeV scale with gauged U(1) N from E 6 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 15

16 Higgs mass bounds in SUSY Models SFK,Moretti,Nevzorov E 6 SSM Higgs mass bound NMSSM MSSM 2-loop Higgs mass bounds tan β mh λ v sin 2β + MZ cos 2β 2 NMSSM MSSM In E 6 SSM, λ can be larger than in the NMSSM 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 16

17 NMSSM benchmarks Djouadi et al 08 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 17

18 h aa may dominate, with a bb or τ τ 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 18

19 Fine tuning in NMSSM vs MSSM 1% Fine tuning Bastero-Gil, Hugonie, SFK, Roy, Vempati 00 Fine tuning about 2% in MSSM 2% 10% tan β = 5 Fine tuning is reduced to about 10% in NMSSM Higgs mass 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 19

20 E 6 SSM SFK, Moretti, Nevzorov E6 SO(10) U(1) ψ Right handed neutrinos are neutral under: SO (10) SU (5) U (1) χ U(1) = U(1) + U(1) N ψ 4 χ E 6 broken via SU(5) chain Z ( N) RH ν masses M GUT M 3 M 2 M 1 E 6 SU(5) U(1) N Quarks, leptons SM U(1) N Triplets and Higgs Singlets and RHν s 27',27' H,H -bar To achieve GUT scale unification we add non-higgs TeV M W U(1) N broken, Z (N) & triplets get mass, μ term generated SU(2) L U(1) Y broken 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 20

21 Matter content of E 6 SSM at TeV Quarks and Leptons EXOTIC D,D-bar 27 i Three families of Higgs (Six Higgs doublets!) Singlets Right-handed neutrinos (superheavy) EXOTIC Vector leptons Plus a TeV scale Z (N) Plus all their SUSY superpartners Message: E 6 SSM predicts SUSY+ EXOTICS at LHC 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 21

22 Unification in E SSM 6 2 loop, α 3 (M Z )=0.118 Blow-up of GUT region α 3 α 2 α 1 SFK, Moretti, Nevzorov 250 GeV 1.5 TeV /05/2009 Steve King, UK HEP Forum '09, Abingdon M GUT GeV

23 Athron, SFK, Miller, Moretti, Nevzorov The Constrained E SSM 6 W λsh H + κ SDD i u, i d, i i i i Low Mass Benchmark Points EWSB, LEP, 2-loop RGE 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 23

24 A B CE 6 SSM Low Mass Benchmarks Athron, SFK, Miller, Moretti, Nevzorov C D 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 24

25 Light gauginos are a general prediction of CE 6 SSM M M 1 2 g Gluino M M 1 2 χ, χ ± Wino M1 0.15M χ 1 Bino c.f. MSSM M i = αi α GUT M Since with α α GUT in E 6 SSM 1/2 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 25

26 Z (E 6 ) limits Chris Hays et al 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 26

27 Z (N) M g < S > ' Z 1 SFK,Moretti,Nevzorov 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 27

28 D fermions Usual case is of scalar leptoquarks, here we have novel case of D being fermionic diquarks or fermionic leptoquarks Inv. mass distribution md = 300GeV Total cross section SFK,Moretti,Nevzorov SFK,Moretti,Nevzorov Fermionic diquarks D Fermionic leptoquarks D 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 28

29 D hadrons It is possible that D fermions are very long lived (lifetime up to 1 sec) giving jets containing heavy long lived D-hadron D-hadrons resemble protons or neutrons but with mass >300 GeV: D = Du, D = Dd p n Clean events with two D-jets containing a pair of stable D-hadrons D p or D n p p D p or D n c.f. R hadrons, stable gluinos, etc.. 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 29

30 SFK, Hall Dark Matter from Inert Higgsinos 3 families of Higgs = 1 MSSM family H u, H d + 2 inert families H u1, H d1, H u2, H d2 3 families of Singlets = 1 NMSSM singlet S + 2 inert singlets S 1, S 2 SUSY partners to inert Higgsinos are good dark matter candidates, which may be almost decouped from the usual MSSM neutralinos and lighter LSP is naturally light LSP is mainly inert singlino 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 30

31 Contours of Ω and LSP mass SFK, Hall tan β λ 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 31

32 Conclusion Good motivations for BSM physics Many possibilities: Extra dimensions, TC, SUSY... MSSM problems NMSSM, E6SSM (light/heavy higgs) NMSSM: higgs phenomenology changed e.g. h aa E 6 SSM has light gaugino spectrum and predicts lots of exotics: Z, D-fermions, inert Higgs/higgsinos Neutralino Dark Matter could originate from an almost decoupled sector of inert Higgsinos relaxes parameter space of SUSY models SUSY promises the most but CC and sflavour/cp? Sflavour/CP problem may be addressed by a theory of flavour that describes the quark and lepton spectrum e.g. SU(3) family symmetry (Antusch, SFK, Malinsky, Ross) 08/05/2009 Steve King, UK HEP Forum '09, Abingdon 32

The Constrained E 6 SSM

The Constrained E 6 SSM and its signatures at the LHC Work with Moretti and Nevzorov; Howl; Athron, Miller, Moretti, Nevzorov Related work: Demir, Kane, T.Wang; Langacker, Nelson; Morrissey, Wells; Bourjaily;