Beyond the MSSM. Beyond the MSSM. Heavy Z. Higgs. Neutralinos. Exotics. Neutrino Mass in Strings

Transcription

1 Beyond the MSSM Beyond the MSSM Heavy Z Higgs Neutralinos Exotics Neutrino Mass in Strings

2 References J. Kang, P. Langacker, T. j. Li and T. Liu, Electroweak baryogenesis in a supersymmetric U() model, Phys. Rev. Lett. 94, 68 (5), hep-ph/486. J. Kang and P. Langacker, Z discovery limits for supersymmetric E(6) models, Phys. Rev. D 7, 354 (5), hep-ph/49. J. Erler, P. Langacker and T. j. Li, The Z Z mass hierarchy in a supersymmetric model with a secluded U() - breaking sector, Phys. Rev. D 66, 5 (), hep-ph/5. V. Barger, C. W. Chiang, J. Jiang and P. Langacker, B s B s mixing in Z models with flavor-changing neutral currents, Phys. Lett. B 596, 9 (4), hep-ph/458. T. Han, P. Langacker and B. McElrath, The Higgs sector in a U() extension of the MSSM, Phys. Rev. D 7, 56 (4), hep-ph/4544.

3 V. Barger, PL and H. S. Lee, Lightest neutralino in extensions of the MSSM, Phys. Lett. B 63, 85 (5), hep-ph/587 J. Giedt, G. L. Kane, P. Langacker and B. D. Nelson, Massive neutrinos and (heterotic) string theory, Phys. Rev. D 7, 53 (5) hep-th/53. P. Langacker and B. D. Nelson, String-inspired triplet see-saw from diagonal embedding of SU() L in SU() A SU() B, Phys. Rev. D 7, 533 (5), hep-ph/5763. Higgs Sector in Extensions of the MSSM, V. Barger, PL, H.S. Lee and G. Shaughnessy, hep-ph/6347. Quasi-Chiral Exotics, J. Kang, PL and B. Nelson, to appear

4 Beyond the MSSM Even if supersymmetry holds, MSSM may not be the full story Most of the problems of standard model remain (hierarchy of electroweak and Planck scales is stabilized but not explained) µ problem introduced: W µ = µĥ u Ĥ d, µ = O(electroweak) Could be that all new physics is at GUT/Planck scale, but with remnants surviving to TeV scale Specific string constructions often have extended gauge groups, exotics, extended Higgs/neutralino sectors Important to explore alternatives/extensions to MSSM

5 Z or other gauge Remnants Physics from the Top-Down Extended Higgs/neutralino (doublet, singlet) Quasi-Chiral Exotics Charge / (Confinement?, Stable relic?) Quasi-hidden (Strong coupling? SUSY breaking? Composite family?) Time varying couplings LED (TeV black holes, stringy resonances) LIV, VEP (e.g., maximum speeds, decays, (oscillations) of HE γ, e, gravity waves (ν s))

6 A TeV-Scale Z Strings, GUTs, DSB, little Higgs, LED often involve extra Z Typically M Z > 6 9 GeV (Tevatron, LEP, WNC); θ Z Z < few 3 (Z-pole) (CDF di-electron: 85 (Z seq ), 74 (Z χ ), 75 (Z ψ ), 745 (Z η )) Discovery to M Z 5 8 TeV at LHC, ILC, (pp e + e, µ + µ, q q) (depends on couplings, exotics, sparticles) Diagnostics to - TeV (asymmetries, y distributions, associated production, rare decays)

7 String models Extra U() and SM singlets extremely common Radiative breaking of electroweak (SUGRA or gauge mediated) often yield EW/TeV scale Z (unless breaking along flat direction intermediate scale) Breaking due to negative mass for scalar S (driven by large Yukawa) or by A term

8 Implications of a TeV-scale U() Natural Solution to µ problem W hsh u H d µ eff ( stringy version of NMSSM) = h S Extended Higgs sector Relaxed upper limits, couplings, parameter ranges (e.g., tan β can be close to ) Higgs singlets needed to break U() Doublet-singlet mixing highly non-standard collider signatures Large A term and possible tree-level CP violation (no new EDM constraints) electroweak baryogenesis

9 Extended neutralino sector Additional neutralinos, non-standard couplings, e.g., light singlino-dominated, extended cascades Enhanced possibilities for cold dark matter, g µ (even small tan β) Exotics (anomaly-cancellation) May decay by mixing; by diquark or leptoquark coupling; or be quasi-stable Z decays into sparticles/exotics Constraints on neutrino mass generation Flavor changing neutral currents (for non-universal U() charges) Tree-level effects in B decay competing with SM loops (or with enhanced loops in MSSM with large tan β)

10 Extended Higgs Sector Standard model singlets S i and additional doublet pairs H u,d very common. Additional doublet pairs Richer spectrum, decay possibilities May be needed (or expand possibiities for) quark/lepton masses/mixings (e.g., stringy symmetries may restrict single Higgs couplings to one or two families) Extra neutral Higgs FCNC (suppressed by Yukawas) Significantly modify gauge unification

11 Higgs singlets S i Standard model singlets extremely common in string constructions Needed to break extra U() gauge symmetries Solution to µ problem (U(), NMSSM, nmssm) W h s ŜĤ u Ĥ d µ eff = h s S Relaxed upper limits, couplings, parameter ranges (e.g., tan β = v u /v d can be close to ), singlet-doublet mixing Large A term and possible tree-level CP violation electroweak baryogenesis

12 Dynamical µ Higgs Sector in Extensions of the MSSM, V. Barger, PL, H.S. Lee and G. Shaughnessy, hep-ph/6347 V. Barger, PL and H. S. Lee, Lightest neutralino in extensions of the MSSM, Phys. Lett. B 63, 85 (5), hep-ph/587 Abel, Bagger, Barger, Bastero-Gil, Batra, Birkedal, Carena, Chang, Choi, Cvetic, Dedes, Delgado, Demir, Dermisek, Dobrescu, Drees, Ellis, Ellwanger, Erler, Espinosa, Everett, Fox, Godbole, Gunion, Haber, Han, Hooper, Hugonie, Kaplan, King, Landsberg, Li, Matchev, McElrath, Menon, Miller, Moretti, Morrissey, Nevzorov, Panagiotakopoulos, Perelstein, Pilaftsis, Poppitz, Randall, Rosner, Roy, Sarkar, Sopczak, Tait, Tamvakis, Vempati, Wagner, Weiner, White, Zerwas, Zhang

13 Models with Dynamical µ Model Symmetry Superpotential CP-even CP-odd MSSM µĥ u Ĥ d H, H A NMSSM Z 3 h s ŜĤ u Ĥ d + κ 3 Ŝ3 H, H, H 3 A, A nmssm Z R 5, ZR 7 h s ŜĤ u Ĥ d + ξ F M nŝ H, H, H 3 A, A UMSSM U() h s ŜĤ u Ĥ d H, H, H 3 A smssm U() h s ŜĤ u Ĥ d + λ s Ŝ Ŝ Ŝ 3 H, H, H 3, A, A, A 3, A 4 H 4, H 5, H 6 MSSM: gaugino unification but general µ NMSSM: may be domain wall problems (Z R?) nmssm: avoids domain walls; tadpoles from high order loops UMSSM: additional Z (µ eff, M Z generated by single S) smssm: stringy NMSSM w. decoupled µ eff, M Z (Ĥ u, Ĥ d, Ŝ reduces to nmssm in S i decoupling limit n/smssm)

14 A Unified Analysis of Higgs and Neutralino Sectors V F = h s H u H d +ξ F M n +κs + h s S ( H d + H u ) V D = G 8 + g ( Hd H u ) g ( + Hd H u H u H d ) ( QHd H d + Q Hu H u + Q S S ) V soft = m d H d + m u H u + m s S + (A s h s SH u H d + κ3 ) A κs 3 +ξ S M 3n S + h.c. black = MSSM (with µ = h s S ); blue= extensions; cyan = NMSSM; magenta = UMSSM; red= n/smssm

15 Mass matrices in {H d, H u, S} basis CP-even (tree level) ( H u,d v u,d/, S s/ ) (M + ) dd = (M + ) du = (M + ) ds = (M + ) uu = (M + ) us = " # G 4 + Q H g d v d + (h sa s " # G 4 + h s + Q H d Q H ug hh s + Q Hd Q S g i " G 4 + Q Hu g # hh s + Q HuQ S g i v d s ( h sa s v u + (h sa s v u s ( h sa s + h sκs + h sξ F M n s v d v u ( h sa s + h s κs)v u + h sκs ) v us v d + h sκs + h sξ F M n s + h s κs)v d ) v ds v u + h sξ F M n s )s (M + ) ss = h Q S g + κ i s + ( h sa s ξs M 3 n v d v u ) v dv u s + κa κ s

16 Also CP-odd and charged Higgs (CP breaking ignored) Leading loop corrections (top-stop loops) are common Theoretical upper limits on H MSSM M H relaxed ( smaller tan β allowed) M Z cos β + M () M () = (M () + ) dd cos β + (M () + ) uu sin β + (M () + ) du sin β NMSSM, n/smssm, and Peccei-Quinn limits M H M Z cos β + h s v sin β + M () UMSSM M H M Z cos β+ h s v sin β+g Z v (Q Hd cos β+q H u sin β) + M ()

17 with a 95% C. L. Points falling below this curve pass the ZZH i constraint. (b) cos Experimental LEP SM and MSSM bounds may be relaxed by singlet-doublet mixing ξ ZZH.. MSSM NMSSM n/smssm UMSSM LEP limit 95% C.L M H (GeV) Reduced ZZH i coupling.8 ξ ZZHi = (R i + cos (β α).6.4 mass,. Z Z mixing, cos β+ri + MSSM sin β) Also, Z HA, Z width, χ ± V minimum, RGE M A (GeV) (a) (b) FIG. 3: (a) LEP limit [34] on ξ ZZHi = ( g ZZHi /gzzh SM ) = ΓZ ZHi /Γ SM Z Zh, th coupling in new physics, versus the light Higgs mass. The solid black curve is the

18 Limiting Cases MSSM limit (s with µ eff = h s s/ fixed) two MSSM-like CP-even Higgs and one largely singlet (heavy in UMSSM, light in n/smssm, depends on κ in NMSSM) PQ and R limits (massless pseudoscalar) Model Limits Symmetry Effects MSSM B U() P Q M A NMSSM κ, A κ U() P Q M A NMSSM A s, A κ U() R M A n/smssm ξ F, ξ S U() P Q M A UMSSM g U() M Z, M A

19 CP Even CP Odd Higgs Mass (GeV) 5 5 MSSM NMSSM n/smssm UMSSM PQ Limit s = 5 GeV Higgs Mass (GeV) 5 5 MSSM NMSSM n/smssm UMSSM PQ Limit s = 5 GeV tan β tan β (a) (b) CP Even CP Odd Higgs Mass (GeV) 5 5 MSSM NMSSM n/smssm UMSSM PQ Limit tan β = Higgs Mass (GeV) MSSM NMSSM n/smssm UMSSM PQ Limit tan β = s (GeV) (c) s (GeV) (d) (A s = M n = 5 GeV, A κ = 5 GeV, h s = κ =.5, ξ F,S =.) FIG. : Lightest CP-even and lightest CP-odd Higgs masses vs. tan β and s for the MSSM, NMSSM, n/smssm, UMSSM, and the PQ limits. Only the theoretical constraints are applied with s = 5 GeV (for tan β-varying curves), tan β = (for s-varying curves). Input parameters of A s = 5 GeV, A t = TeV, M Q = MŨ = TeV, κ =.5, A κ = 5 GeV, M n = 5 GeV,

20 NMSSM n/smssm ξ MSSM H H H 3 A A ξ MSSM H H H 3 A A.. Higgs Mass (GeV) Higgs Mass (GeV) (a) (b) UMSSM Lightest Higgs ξ MSSM H H H 3 A ξ MSSM NMSSM n/smssm UMSSM.. Higgs Mass (GeV) (c) Higgs Mass (GeV) (d) (MSSM FIG. fraction 4: Higgs masses ξ H i MSSM vs. = P u ξ MSSM j=d in (Rij the + (a) ) NMSSM, ) (b) n/smssm, (c) UMSSM and (d) the lightest CP-even Higgs of all extended models. The vertical line is the LEP lower bound on the GalileoMSSM Institute (SM-like) (6 June, Higgs 6) mass.

21 CP-Even Higgs Mass Range CP-Odd Higgs Mass Range MSSM Scan NMSSM Scan n/smssm LEP 9 Th. 35 Th. 64 Th. 7 LEP MSSM 94 Th. State Crossing NMSSM 63 Th. State Crossing n/smssm 7 Scan 685 UMSSM LEP & α ZZ 9 Th. 73 LEP & α ZZ UMSSM 93 Scan Higgs Mass (GeV) 4 6 Higgs Mass (GeV) Charged Higgs Mass Range LEP MSSM 79 LEP NMSSM 83 LEP n/smssm 8 LEP UMSSM 8 Scan 48 Scan 359 Scan 6873 Scan Higgs Mass (GeV) FIG. : Mass ranges of the lightest CP-even and CP-odd and the charged Higgs bosons in each

22 Lightest Higgs Decays Partial Width (MeV).. SM H MSSM H NMSSM H n/smssm H n/smssm H UMSSM W W* Partial Width (MeV).. Z Z* Higgs Mass (GeV) Higgs Mass (GeV) g g Partial Width (MeV) Higgs Mass (GeV) FIG. 9: Decay widths for W W, ZZ, and gg in the MSSM and extended-mssm models. Lines denote the corresponding SM width. For clarity, not all points generated are shown.

23 χ in this model is very light (M χ < GeV). In principle, other annihilation channe such as a very light Higgs may allow the lighter χ although the pole will be quite narro [69]. Furthermore, in the secluded (smssm) version of the model, it is possible that the χ Invisible Decays considered here actually decays to a still lighter (almost) decoupled neutralino, as discusse in Appendix A. Lightest Neutralino Mass (GeV) H MSSM H NMSSM H n/smssm H n/smssm H UMSSM M H = M χ Branching Fraction... χ χ 5 5 Lightest Higgs Mass (GeV) (a) Higgs Mass (GeV) (b) FIG. : (a) M Hi vs. M χ in all the models considered. Points falling below the blue line allo the decay Galileoof Institute the lightest (6 June, CP-even 6) Higgs to two χ. (b) Branching Paul fraction Langacker of (Penn/IAS) H i χ χ

24 H, A A M A (GeV) 5 5 M Z =M H +M A H MSSM H NMSSM H n/smssm H n/smssm M H =M A Branching Fraction... A A 5 5 M H (GeV) (a) Higgs Mass (GeV) (b) FIG. : (a) M H vs. M A showing the kinematics for decays in extended-mssm models. H A A decays are allowed for regions below the blue-dashed line. Decays of Z H A are allowed to the left of the green dark line. (b) H A A branching fraction versus Higgs mass. The

25 Total Width Total Width (MeV) e SM H MSSM H NMSSM H n/smssm H n/smssm H UMSSM 5 5 Higgs Mass (GeV) tal decay Galileo width Institute for (6 June, each 6) model. Large enhancements Paul Langacker with respect (Penn/IAS) to the

26 Lightest Neutralino Mass matrix (M χ ) in basis { B, W 3, H, H, S, Z }: M g v / g v / M g v / g v / g v / g v / µ eff µ eff v /s g Z Q H v g v / g v / µ eff µ eff v /s g Z Q H v µ eff v /s µ eff v /s κs gz Q S s g Z Q H v g Z Q H v g Z Q S s M ( S s, H i v i, p v + v v 46 GeV, Q φ = φ U() charge) (black = MSSM; blue= extensions; cyan = NMSSM; magenta = UMSSM)

27 N 5 (Singlino in χ ) NMSSM nmssm UMSSM N 6 in UMSSM "!! h.. nmssm nmssm WMAP+SDSS (3##.. 3 (GeV) M χ M!"! (GeV) (Relic density in nmssm from χ χ Z only; may be χ secluded in smssm)

28 5 4 tanβ = 7.9 < Δa µ < 39.9 Ω χ h <.9.9 < Ω χ h <.5 s = 5 GeV µ (GeV) 3 h s =.75 M χ ± < 4 GeV Γ Z-->χχ >.3 MeV h s = M (GeV) (Relic density and g µ in n/smssm)

29 5 Masses of χ + vs χ 5 Masses of χ + vs χ M χ > Μ χ + M Z M χ > Μ χ + M h () M χ+ (GeV) 4 3 M + χ > Μ χ + M + W M χ + = M χ M χ + = M χ M χ+ (GeV) 4 3 M + χ > Μ χ + M + W M χ + = M χ M χ + = M χ M + χ < 4 GeV 3 (GeV) M χ NMSSM nmssm UMSSM MSSM M + χ < 4 GeV 3 (GeV) M χ NMSSM nmssm UMSSM MSSM Often χ χ 5 are MSSM-like with light singlino-dominated χ MSSM-like cascades with extra χ χ + (l l, q q, Z, h) Often χ χ + (Z, h); χ+ χ + (W +, H + ) are open (e.g., χ + χ W + h + E T l + b b + E T )

30 Quasi-Chiral Exotics (J. Kang, PL, B. Nelson, in progress) Often find exotic (wrt SU() U()) quarks or leptons at TeV scale Assume non-chiral wrt SM gauge group (strong constraints from precision EW, expecially on extra or mirror families) Can be chiral wrt extra U() s or other extended gauge Usually needed for U() anomaly cancellation Modify gauge unification unless in complete GUT multiplets Can also be more extreme exotics (e.g., adjoints, symmetric, fractional charge, mixed quasi-hidden) Experimental limits relatively weak

31 Examples in 7-plet of E 6 D L + D R (SU() singlets, chiral wrt U() ) ( ) ( ) E E E + E (SU() doublets, chiral wrt U() ) L R Pair produce D + D by QCD processes (smaller rate for exotic leptons) D or D decay by D u i W, D d i Z, D d i H if driven by D d mixing (not in minimal E 6 ; FCNC) m D > GeV (future: TeV) D quark jets if driven by diquark operator ūū D, or quark jet + lepton for leptoquark operator lq D (still have stable LSP) May be stable at renormalizable level due to accidental symmetry (e.g., from extended gauge group) hadronizes and escapes or stops in detector (Quasi-stable from HDO τ < / yr)

32 Neutrino Mass Nonzero mass may be first break with standard model Enormous theoretical effort: GUT, family symmetries, bottom up Majorana masses may be favored because not forbidden by SM gauge symmetries GUT (+ family symmetry) seesaw (heavy Majorana singlet). Usually ordinary hierarchy.

33 Relatively little work from string constructions, even though may be Planck scale effect Key ingredients of most bottom up models forbidden in known constructions (heterotic or intersecting brane) (Due to string symmetries or constraints, not simplicity or elegance) Right-handed neutrinos may not be gauge singlets Large representations difficult to achieve (bifundamentals, singlets, or adjoints) GUT Yukawa relations broken String symmetries/constraints severely restrict couplings, e.g., Majorana masses, or simultaneous Dirac and Majorana masses

34 Neutrino Mass in Strings Dirac masses Can achieve small Dirac masses (neutrino or other) by higher dimensional operators or by large intersection areas L ν ( S M P l ) p LN c L H, S M P l m D ( S M P l ) p H Large p S close to M P l (e.g., anomalous U() A ) Small p intermediate scale M P l Similar HDO may give light steriles and ordinary/sterile mixing

35 Majorana masses Existing intersecting brane models: conserved L; no diagonal (Majorana) triangles Heterotic: can one generate large effective m S from S q+ S q+ W ν c ij N i N j (m S ) ij c ij, M q P l consistent with D and F flatness? M q P l Can one have such terms simultaneously with Dirac couplings, consistent with flatness and other constraints? Are bottom-up model assumptions for relations to quark, charged lepton masses maintained?

36 The Z 3 Heterotic Orbifold (Giedt, Kane, PL, Nelson, hep-th/53) Systematically studied large class of vacua Is minimal seesaw common? If rare, possibly guidance to model building Clues to textures, etc. Several models from each of patterns; superpotential through degree 9; huge number of D flat directions reduced greatly by F -flatness Only two patterns had Majorana mass operators S S n NN/M n 3 PL None had simultaneous Dirac operators S S d 3 NLH u/m d 3 PL leading to m > ev (one apparent model ruined by offdiagonal Majorana)

37 Feature of Z 3 orbifold? Or more general? Systematic searches in other constructions important (Is seesaw generic? Rare? Alternatives?) Alternatives: Small Dirac? (by HDO (common in constructions) or LED) Extended seesaw? m ν m +k /M +k, with k (TeV scale physics?) Loops, R P breaking? (TeV physics) Higgs triplet? (higher Kač-Moody or intersecting brane) D Higher Kač-Moody embedding in heterotic string (PL, B. Nelson, hep-ph/5763) Inverted hierarchy with bimaximal mixing Solar mixing non-maximal small (Cabibbo-like) charged lepton mixing U e3 close to Chooz limit

38 Conclusions Combination of theoretical ideas and new experimental facilities may allow testable theory to Planck scale From the bottom up: there may be more at TeV scale than (minimal SUGRA) MSSM (e.g., Z, extended Higgs/neutralino, quasichiral exotics) From the top down: there may be more at TeV scale than (minimal SUGRA) MSSM Dynamical µ term leads to very rich Higgs/neutralino physics at colliders and for cosmology Consider alternatives to the minimal seesaw