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Exploring the Two Higgs Doublet Model: Past and Future Perspectives

Dive into the intricate world of the Two Higgs Doublet Model (2HDM) and its implications on Electroweak Symmetry Breaking (EWSB), flavor physics, and LHC experiments. Discover past research, ongoing advancements, and potential future discoveries in this fascinating field. The text highlights key findings, missed opportunities, and the importance of flavor connections in the Higgs sector.

margaretjmoore
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Exploring the Two Higgs Doublet Model: Past and Future Perspectives

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  1. Two Higgs Doublet Model: Past and Future February 21, 2014, EWSB-Flavours-LHC @ Guwahati

  2. 2HDM: Past & Future EWSB-Flavour-LHC • Intro:Flav H ➾ EWSB Soni; H+; Enhanced “Murky”; Top-Higgs • Let’s Do H+: b → sg(g) • “Murky Mode” @ 10%: b → ctn &b → sg ➥ B → D(*)tn; tn • FCNH: Model III & t → ch0 • LHC • Conclusion ➾ More on “Lost Opportunities” (from my past dabbles) and Good Pheno Link

  3. The “God” Particle: the Origin of Mass Fermion: Repeated Doublets Higgs: Second Doublet Flavour Sector mF~lFυ Weinberg, 1967 mV~gυ (Agent of) EWSB B.E.H., 1964 VL“seen” since 1983

  4. 2HDM Will focus on Flavour Connection p.s. parameters in Higgs sector always give me the shudders …

  5. Thanks, Soni! WSH, Soni, Steger, b → sg PLB’87 WSH, Soni, Steger, b → sg* PRL’87 WSH, Soni, Bd & Bs Mixing PLB’87 WSH, Willey, Soni, b → sℓ+ℓ- PRL’87 4G Introduced me to B Physics. But I missed “large QCD corrections” by focusing too much on New Physcs… Bertolini, Borzumati, Masiero, PRL’87 Deshpande, Trampetic, Eilam, Singer, PRL’87 ➥ Operator Analysis: Culmination in M. Misiak!

  6. Thanks, Soni! WSH, Soni, Steger, b → sg PLB’87 WSH, Soni, Steger, b → sg* PRL’87 WSH, Soni, Bd & Bs Mixing PLB’87 WSH, Willey, Soni, b → sℓ+ℓ- PRL’87 4G Introduced me to B Physics. Timelike Lightlike Spacelike

  7. Before summer 1987, before moving from Pitt to Munich, saw this paper ... and said to Ray Willey, “We can easily do this, too.” b → sg Turned out they focus on large tanb … and missed a crucial sign. H+effect

  8. Usual 2HDM Framework: NFC

  9. H+ Couplings in Model I/II “SUSY” (mindset: ~ mt/mb)

  10. • Ca. 1990: Bs.l. (semileptonic BR) and NC (charm counting) problem. Could there be Enhanced “Murky” Modes? ➥ Polish synergy: B → D(*)tn; B →tn • 1992: CDF bound of mt > 91 GeV Could top be still lighter? t → ch0 Non-NFC: Model III

  11. 2HDM: Past & Future EWSB-Flavour-LHC • Intro:Flav H ➾ EWSB Soni; H+; Enhanced “Murky”; Top-Higgs • Let’s Do H+: b → sg(g) • “Murky Mode” @ 10%: b → ctn &b → sg ➥ B → D(*)tn; tn • FCNH: Model III & t → ch0 • LHC • Conclusion ➾ More on “Lost Opportunities” (from my past dabbles) and Good Pheno Link

  12. Let’s Do H+: b → sg(g)

  13. b → sg(g) logarithmic vs power GIM suppression in SM QCD corr. brings in large log

  14. ξ2 = cot2b, ξξ′= ξ2(Model I), -1 (Model II) why does ξ′ enter? fig. stolen from Hermann, Misiak, Stenihauser

  15. ξ2 = cot2b, ξξ′= ξ2(Model I), -1 (Model II) why does ξ′ enter? fig. stolen from Hermann, Misiak, Stenihauser

  16. ξ2 = cot2b, ξξ′= ξ2(Model I), -1 (Model II) NNLO fig. stolen from Hermann, Misiak, Stenihauser, JHEP’12

  17. State of the Art Hermann, Misiak, Stenihauser, JHEP’12 [1208.2788] Can be weakened by BSM Exp 1s SM 1s WSH & Willey NPB’89

  18. “Murky Mode” @ 10%: b → ctn &b → sg ➥ B → D(*)tn; tn (mn

  19. The Polish Connection/Synergy b → ctn part based on Krawczyk and Pokorski, PRL’88 SM ~ 3% ~ 0.2%

  20. ca. 1991 Sol. 2: b → ctn @ 10% Sol. 1: b → sg @ 10% charm counting charm counting ~ SM ~ SM Great Pheno If True !

  21. PLB’92 7 s-wave enhanced 5 3 Form Factors tr. long. scalar ➥ t polarization Flip Kalinowski, PLB’90

  22. ALEPH Exclusion of b → ctn @ 10%; and then … b →tn + X = (4.08 ± 0.76 ± 0.62)% PLB’93 (2.75 ± 0.30 ± 0.37)% PLB’95 (2.43 ± 0.20 ± 0.25)% EPJC’01 ➙ SM-like, rule out enhanced b → ctn = (1.05 ± 18)% saturate inclusive (PDG’13) expected = (1.64 ± 15)% a crisp result: no new hadronic effect beyond fB within SM cf.

  23. Crisp B →tn Surprise

  24. anybody out there? cottage industry When First Evidence in 2006, citations soared. A Driver for Super B Factory

  25. An Illustration towards 2015+ Stole from my own FPCP2012 Talk No serioussign of Godot in FPCP ... Roderjohann; Soni • Old Tensions: e.g. Or, But, B →mn almost touched by BaBar/Belle. Super B Factory (2015 for Belle 2) would unravel it “immediately”. Totally different systematics! Lüth Which One ? Hara Finally underway in my own group …

  26. FCNH: Model III & t → ch0 11/1991 Became relevant recently at the LHC

  27. 2HDM III: “Natural” FC Neutral Higgs 2HDM Framework: NFC FCNH from B Phys.

  28. FCNH: t → ch0& Model III Thy Shall Not Mix 4G – 2HDM – FCNH ! “a3”

  29. FCNH: t → ch0& Model III S/P S/P t → ch0/ t → bW* h0→ tc/ h0→ bb & tt 1% benchmark

  30. Mass Pro-found if Found FCNH: verboten in SM & 2HDM I/II Glashow-Weinberg 1977 Outline • BaBar Anomaly,2HDM-III&tch0 Coupling • B Physics & H →ttConstraints • t→ch0Search at LHC c ► h0 ► ZZ* gg WW* t bb C.Kao talk Fajfer, Kamenik, Nisandzic, Zupan, PRL 2012 Crivellin, Greub, Kokulu, PRD 2012; 1303.5877 KCHS CHKK Kao,Cheng,WSH,Sayre,PLB 2012 Chen, WSH, Kao, Kohda, 1304.8037 CGK

  31. BaBar “Anomaly” BaBar, PRL 2012 Very (too) Large!

  32. CGK considered Decoupling Limit: SMH 2HDM-III (General) Yukawa Interactions Crivellin, Greub, Kokulu, PRD 2012 [we use notation of Mahmoudi and Stal, PRD 2010 “Standard” Exotic 23 To consider t→ch0: FCNH • Need Nondecoupling: h0 mixes in cos(b-a) frac. of H0 • Not only rbb, but rtt turn out small (next page)  deviate from CGK [left with mH+ pockets •rct ~ 1, implying rtt and rcc need be considered!

  33. With Regrets, “detach” from BaBar anomaly B & H → tt Constraints mH+ pockets remain t→ch0Search at LHC How large can B(t → ch0) be? If rct~ 1, what constraint we have on cos(b-a) ? N.B. From stt(bar) measurement with dileptons, one infers B(t → ch) cannot be larger than few %.

  34. Summary of Constained 2HDM-III rcc, rtt rct New Sector to be probed at the LHC

  35. No Evidence of Excess Jets in ZZ* … ? Any tt(bar) → chbW? Illustration Simple CLs estimate gives (95% C.L.) B(t → ch) < 1.5% Is there bias even in ZZ*? 2.2% Best done directly by the Experiments ATLAS 4ℓ + 4j evt (backup) Craig et al., PRD 2012: < 2.7% (can improve) KCHS’12: Can probe down to 1%

  36. Comments ∙ gg + 4j, gg + jj + ln : [gg in Higgs window] Because of background concerns, evts perhaps rejected by Dh (VBF)  Even the study of such BG may be interesting; b/t tags if found. ATLAS announced at Higgs Hunting, Orsay, week after EPS: t → cHgg< 0.83% at 95 C.L. ATLAS-CONF-2013-081 ∙ WW* + jets, WW* + jets + W : [no Higgs Mass] Astounding: % level bound year after Higgs discovery ! Can be Improved CMS announced at SUSY2013: t → chmult-ℓ< 1.28%at 95 C.L. CMS PAS-SUS-13-002

  37. 2HDM H+ Search at LHC LHC Search has Started ! a BaBar-centric View Eli Ben-Haim @ EPSHEP2013

  38. t → bH+Search at LHC ATLAS JHEP’12 CMS JHEP’12

  39. t → bH+ & H+→ tb at LHC ATLAS-CONF-2013-081 entered H+→ tb t → bH+: getting there

  40. finally getting there

  41. Conclusion: 2HDM I, II & III BaBar throws in B → D(*)tn monkey wrench ➥ Rule out 2HDM II ? Haisch0805.2141 need Belle-II (2015+) B →tn b → sg FCNH t → ch0 Search Underway 2015+ Looks Bright finally getting there

  42. Is “the Higgs” the Agent of BEH Mech.? Outline EWSB 12/2013 Dilaton : Goldstone boson of SSB of Scale Invariance

  43. υ/F

  44. How does Dilatonfake Higgs? H → ZZ* →eemm cg but, no convincing evidence for VBF (Vector Boson Fusion) or VH (Higgsstrahlung off V) so far Dilaton υ/F ➙ Check Dilaton 2015+ ! cgυ/F ~ SM Higgs cgcg~ SM Higgs Leading Processes cg cg fortuitous, maybe … Dilaton H →gg

  45. B →tn Satus

  46. Data-constrained 2HDM-III ~ SM Higgs →tt : rtt small b → sg : rbb tiny Nonperturb. rct needed With Regrets, “detach” from BaBar anomaly Because of chiral mt/mb and KM enhancement, rbb tiny! mH+ pockets remain

  47. Example: Clean Sample of ZZ*→4ℓ Consistency of 15-20 evts ~ SM w/ little BG, for both CMS/ATLAS ~ 22 pb With 126 GeV dominantly SMH, i.e. sin(b-a) ≃ 1 (near Decoupling), ZZ* (and WW*) Rate hard to change. The width of 126 GeV Higgs can be enhanced by rcc as not measured. Gluon Fusioncan be enhanced by rtt, even though damped by cos(b-a). Cf.: stt(bar)~ 220 pb, if t → ch 2%, then tt(bar) → chbW is at 9 pb! Could we have seen it already!?

  48. One ATLAS eemm + 4j Event! “Passed VBF Selection” Is there bias even in ZZ*? h = -2.20 h = 1.19 ATLAS-CONF-2013-013, (extra) Fig. 38 [thanks to Bill Murray is there a b?

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