1. Supersymmetric Models with 125 GeV Higgs Masahiro Yamaguchi (Tohoku University) 17 th Lomonosov Conference on Elementary Particle Physics Moscow State University, 20-26 August, 2015 1

2. Higgs Boson Higgs Boson Mass LHC combined 125.09±0.21(stat. )±0.11(syst. ) GeV Signal Strength for Decay Modes CMS combined 1.00±0.14 ATLAS combined 1.18±0.15 consistent with SM prediction still some room to play with (room for BSM) 2

3. Motivations for Supersymmetry Unnaturalness of Higgs Sector: – gauge hierarchy problem/naturalness problem Unification of forces: Grand unification Muon g-2: possible deviation from SM Call for Beyond SM – Neutrino masses and mixings – Cosmology Connection Dark Matter, Baryogenesis, Dark Energy, Inflation 3

4. SUSY Search 4

5. Higgs Mass in MSSM In MSSM SUSY  Higgs Self Coupling = gauge coupling m h < m Z @tree level (SUSY relation) Large SUSY breaking loop effect can raise the Higgs mass stop-top loops 1) large log m stop /m top 2) finite A-term(stop-stop-Higgs coupling) contribution Inoue et al ‘85 Okada, MY, Yanagida ’91 Haber, Hempfling Ellis, Ridolfi, Zwirner 5

6. Higgs Mass @3-loop Hahn, Heinemeyer, Hollik, Rzehak, Weiglein, 2014 6

7. Challenge to Low Energy SUSY? To achieve the observed Higgs mass (125 GeV), we need either 1)Heavy stop ( ～ 7TeV) and/or large stop mixing in MSSM or 2) Addition of new source of Higgs mass at TeV scale e.g. Vector-like Generation (T+Tbar) Additional Gauge Sym. (eg. U(1) B-L sym.) Singlet Extension 7

8. Singlet Extensions New Sources to increase Higgs Mass 1)tree-level coupling  (significant only for small tan  ) 2)Higgs/Higgsino loop (>0, for heavy singlet boson) 3) Doublet-Singlet Mixing (>0, for light singlet boson) If singlet boson is light, mixing increases doublet Higgs mass. Jeong, Shoji & MY ‘11, ‘12, ’14 Choi, Im, Jeong & MY ‘12  2 |H u H d | 2 : new contribution to the Higgs potential superpotential New coupling: Higgs-Higgsino-Singlino 8

9. Doublet-Singlet Mixing in CP even Higgs sector Mixing terms in Scalar Sector Mass^2 matirx for doublet and singlet Higgses Mass eigenstates: three mixing angles θ 2 : mixing between h and s 9

10. Relations Constraint on mixing  upperbound on higgsino mass parameter  (see below.) 10

11. Coupling of SM-like Higgs boson with  from top-stop sector  Chargino loop Mixings with singlet and with heavier doublet  Change of SM-like Higgs coupling 11

12. LHC Constraints on Higgs mixing Signal Strength (relative to SM expectation) With Singlet  Experimental Constraints 2014 Summer Mainly ggFMainly VBF 12

13. Experimental Constraints Mixings compatible with LHC data within 1sigma(2 sigma) ATLAS CMS tan  =5 10 15 θ 2 : mixing between h and s C b ̴ 1 C b ̴ -1 13

14. LEP Constraint on Singlet-like Higgs s e + e -  Z s  Z bb LEP constaint is not severe if singlet is heavier than 90 GeV. 14

15. Contours of Higgsino mass parameter  tan  =5 tan  = 10 Approximate Higgsino mass parameter: obtained from the previous relations yellow: no solution to 125 GeV Higgs White: λ >1 (Landau pole) Cyan: μ <100 GeV (excluded) 15

16. Summary so far: Doublet-Singlet Mixing in NMSSM 1) realizes m_h=125 GeV by the mixing 2) satisfies LEP constraint on singlet s 3) is compatible with LHC Higgs data 4) favors Relatively Light Higgsino 16

17. Comment on heavy stop case in MSSM Case of Non Universal Higgs Model (NUHM) A slice of allowed parameter regions (at GUT scale) In the bulk, all superparticles are heavy >> LHC reach But near boundary, some of superparticles become light, accessible at LHC Price: severe fine tuning of parameters 17

18. Case of NUHM Interesting cases  light stop (only one of two stops)  light first two generation squarks  light Higgsinos  light pseudoscalar A  light sleptons with muon g-2 within 1 sigma MY & Yin, in preparation 18

19. Conclusions 125GeV Higgs appears a challenge to low energy SUSY. MSSM: Heavy Stop (>>LHC bound) – Possible to have some light superparticles even in this case (explicit demonstration in NUHM) Alternatives to MSSM – New vector-like generation – Gauge symmetry – Singlet  richer Higgs sector & neutralino sector Rich phenomenology expected at LHC RUN2 in either case Stay tuned! 19

20. Thank you very much! 20