vor / H igg gg s Era Exptl NTU NTU George W.S. Hou (NTU) - PowerPoint PPT Presentation

Decadal Decadal Mission for the New H igg ggs / F lavo avor Era Sept 22, 2020, Colloquium @ NTU Disclaimer: In this talk, not all wordings are precise. George W.S. Hou (NTU) Colloquium 09/22/20 1 Flav/HIG

Decadal Mission Decadal for the New F lavor vor / H igg gg s Era Expt’l NTU NTU George W.S. Hou (NTU) Colloquium 09/22/20 2 Flav/HIG

Decadal Mission Decadal for the New H igg ggs / F lavo avor Era I. Prelude: Dynamics, Mass, “ Flavor ” , Universe m e e + μ e II. Standard Model, the Higgs , and Mass Generation e ; g ; W, Z vs γ , g g s Φ  h V( Φ ) V KM III. “ Totalitarian Principle ” & a Second Higgs  Φ' ?  H , A , H  V( Φ , Φ' ) IV. Big Issues & New Higgs / Flavor Era Heaven / Earth; Spectrum for LHC; Nature ’s Design V. Conclusion: Decadal Mission George W.S. Hou (NTU) Colloquium 09/22/20 3 Flav/HIG

I. Prelude: Dynamics, Mass, “ F l avor ” , Universe Decadal Prehistory: 1896 – 1911 J.J. Thomson Our Common Heritage Ernest Rutherford electron Henri Becqurel a, b, g radioactivity H. Kamerlingh Onnes Weak Interaction “ Four-Fermi ” superconductivity George W.S. Hou (NTU) Colloquium 09/22/20 4 Flav/HIG

The Constituents of Matter Decadal m μ /m e ≃ 207 e : Why Real? m e : What Gives? I.I. Rabi e + : Where Gone? μ : Who Ordered? George W.S. Hou (NTU) Colloquium 09/22/20 5 Flav/HIG

The Fundamental Fermions Decadal structureless Heav eavy Fla lavor vor m t e u c t 1895 1936 1975 1974 1995 3 copies n e n m n t The Problem of Mass d s b 1956 1962 2000 1977 1947 six leptons six quarks George W.S. Hou (NTU) Colloquium 09/22/20 6 Flav/HIG

e + μ the start of Particle Physics Decadal anti-electron m μ /m e ≃ 207 Pb 1 February 1948 1948 Phys. Rev. 73 73 μ ≠ e * μ → e γ e + : Where Gone? Baryon Asymmetry of the Universe (BAU) 1932 – 1947: Birth of Particle Physics George W.S. Hou (NTU) Colloquium 09/22/20 7 Flav/HIG

Discovery of CP V iolation  BaryoGenesis Decadal Sakharov Conditions Backdrop: Parity Violation ( 宇稱不守恆 , Lee-Yang − C.S. Wu , 1956 ) Penzias & Wilson , ApJ ’ 65 [CMB] (1967) CPV & BAU (& U) : The Sakharov View • Baryon ryon Number er Violatio lation • ( C &) CP Violation • Deviation from Equilibrium (H-bomb ...) Peace Prize George W.S. Hou (NTU) Colloquium 09/22/20 8 Flav/HIG

Decadal β / μ Decay, Weak Interaction, W/Z Vector Bosons Rutherford M W ≃ 80.4 GeV/c 2 M Z ≃ 91.2 GeV/c 2 Fermi S.S.B. SU(2)xU(1) U Q (1) g e e e M γ  0 quark/parton p Deeply Inelastic Scattering George W.S. Hou (NTU) Colloquium 09/22/20 9 Flav/HIG

Decadal Meissner Effect ― Photon Massive in Superconductor Phil Anderson (R.I.P.) saw through it ... Anderson Haldane (1977) (2016) Magnetic Field damped ~ Photon acquires “ Mass ” Absence of B in SC Higgs Mechanism ! Attentuation, or 1964 penetration depth George W.S. Hou (NTU) Colloquium 09/22/20 10 Flav/HIG

II. Standard Model, the H iggs , and Mass Generation Decadal My picture taken with “ God ” ... George W.S. Hou (NTU) Colloquium 09/22/20 11 Flav/HIG

The “God” Particle: the Origin of Mass Decadal h (125): observed 7/2012 3 copies George W.S. Hou (NTU) Colloquium 09/22/20 12 Flav/HIG

The “God” Particle: the Origin of Mass Decadal h (125): observed 7/2012 l f : Yukawa Couplings to ~ 173 GeV G 0 Unbroken m f = λ f υ / √2 3 copies massless G + from ~ 80 – 90 GeV (/c 2 ) ! ~ 0.5 MeV m V = g υ / 2 υ ≈ 246 GeV G + , G 0 φ +  φ 0  ≠ 0 G + “ eaten ” by Φ = φ 0 υ +h 0 +G 0 S.S.B. W, Z Higgs Mechanism George W.S. Hou (NTU) Colloquium 09/22/20 13 Flav/HIG

The “God” Particle: the Origin of Mass Decadal h (125): observed 7/2012 l f : Yukawa Couplings Expt’lly Affirmed! g ≃ 2m V / υ ca. 2015 t/b/ τ : 2018 λ f ≃ √2 m f / υ μ : 2020 υ ≈ 246 GeV υ ≈ 246 GeV φ +  φ 0  ≠ 0 G + Φ = φ 0 υ +h 0 +G 0 S.S.B. Higgs “potential”: Simple !! V( Φ ) ~ - m 2 | Φ | 2  l | Φ | 4 | φ 0 | 2 = υ 2 ~ m 2 / l  nobelprize.org George W.S. Hou (NTU) Colloquium 09/22/20 14 Flav/HIG

Complex Dynamics : K obayashi- M askawa Sector of SM Decadal rooted in Yukawa Coupli 小林 - 益川 plings ngs Only Charged Current Interactions Change Flavor u i longitudinal W W – J m g V ij l i ~ √2m i / υ d j Wolfenstein parametrization 3x3 “Rotation” Unitary Need presence of all 3 generations ( expt’lly affirmed) to exhibit CPV in Standard Model George W.S. Hou (NTU) Colloquium 09/22/20 15 Flav/HIG

“ Totalitarian Principle ” & a Second Higgs Decadal III. Origin We know of No Reason to Gell-Mann, Nuovo Cim. 4 (1956) S2, 848-866 forbid a Second Higgs, so ... Tot.:  New Scalars ... φ ' + H +  φ ' 0  = 0 Φ' = φ ' 0 H 0 + i A Where Are They? What do They Do? George W.S. Hou (NTU) Colloquium 09/22/20 16 Flav/HIG

Totalitarian-ism Everywhere, then OverKill ...? Decadal Tot.-0 : Weinberg ’ s “ Yukawa ” Term — include in L all terms allowed by symmetry Not forbidden ! Φ ‾ λ e ℓ L Φ e R + h.c. fermion mass generation ! ‾ ~ ‾ Yukawa matrices Y f : q L Y d Φ d R ‾ q L Y u Φ u R ℓ L Y e Φ e R diagonlize Y f : fermion masses Tot.-2 : [ Tot. : found h , remnant of Φ , so  Φ ' , i.e. 2 nd Higgs] 2 nd Yukawa matrices Ρ f : ‾ ~ ‾ q L P d Φ' d R ‾ ℓ L Ρ e Φ' e R q L Ρ u Φ' u R diagonlize Ρ f : ρ f Yuk. matrices (Flavor Changing Neutral Higgs) in general Glashow feared FCNH Couplings too dangerous , and with nondiagonal Weinberg proposed Natural Flavor Conservation: ~ Edict (& Compl plex ex ) Absence of 2 nd Yukawa! [Authoritarian] [ ad hoc ] • Usually implemented by a Z 2 symmetry • “ Model II” automatic w/ Supersymmetry — Popular! George W.S. Hou (NTU) Colloquium 09/22/20 17 Flav/HIG

Unbeknownst to Glashow-Weinberg in 1977 Decadal 1995 Ca. 1983, w/ advent of Si-sensor: B decays |V ub | 2 << |V cb | 2 << |V us | 2 << |V tb | 2  1 Fermion Mass Hierarchy Quark Mixing Hierarchy m 1 << m 2 << m 3 m b << m t λ t ≃ 1 1977 Wolfenstein parametrization (1983) Cheng-Sher 1987: ρ f ~ FCNH may be “ OK ” , if Echoes Mass-Mixing Hierarchy George W.S. Hou (NTU) Colloquium 09/22/20 18 Flav/HIG

Flavor Changing Neutral Higgs FCNH — an Experimental Question Decadal PLB ’ 92 per mille ... sub% H here is h(125) per mille ... % hint! George W.S. Hou (NTU) Colloquium 09/22/20 19 Flav/HIG

Decadal O Lord, our Lord, How Majestic is Thy Name in all the Earth, Who have set Thy Splendor above the Heavens! Psalm 8:1 (of David) IV. Big Issues & New Higgs / Flavor Era 1. Heaven (Baryogenesis) & Earth (e EDM?) 2. H , A , H  Spectrum @ LHC Leading Production Modes 3. Nature ’s Design : What Replaces (Un) Natural Flavor Conservation glimpse of the coming Era George W.S. Hou (NTU) Colloquium 09/22/20 20 Flav/HIG

Decadal George W.S. Hou (NTU) Colloquium 09/22/20 21 Flav/HIG

EWBG & ThO EDM Decadal comp mplex lex ρ t t ACME14 FHS’18 e EDM: λ e Im ρ tt EWBG λ t Im ρ tt robust driver Ruled Out by ACME18! O ( λ t ) ≈ 1 [ ρ tc as backup Mech. to render small? Yes! George W.S. Hou (NTU) Colloquium 09/22/20 22 Flav/HIG

the A dvanced C old M olecule E lectron EDM Experiment Decadal JILA’ 17 (Cornell): < 13 x 10 − 29 e ∙ cm George W.S. Hou (NTU) Colloquium 09/22/20 23 Flav/HIG

comp mplex lex Mech. to render ρ t t Decadal d ThO small ? Yes ! FHS’20 t Splendor in the Heavens ρ ee eN scattering CPV ρ ee simplified “Ansatz” Beautiful on Earth Follow SM Hierarchy ! N.B. r depend on loop functions George W.S. Hou (NTU) Colloquium 09/22/20 24 Flav/HIG

14 TeV (c.m.s.) H , A , H + Spectrum Fit for the LHC Decadal “ min. cond. ” WSH&Kikuchi, EPL’18 unnatural η 6 : sole param. for h-H mixing (c γ ) Dim ’ less params. O (1) (Naturalness): H , A , H + incredulous N.B. O (1) η i ’ s needed for 1 st order Phase Trans., prerequisite for ElectroWeak BaryoGenesis. George W.S. Hou (NTU) Colloquium 09/22/20 25 Flav/HIG

14 TeV (c.m.s.) Leading Search Modes at the LHC Decadal Efe Yazgan @ CERN (NTU since 2/2020 ) Kohda, Modak , WSH, PLB’18 ρ tc ρ tc cg → tH/A → ttc(bar) Same-Sign Top ρ tt → ttt(bar) Triple-Top (High Lumi LHC; H , A , H + higher mass, more exquisite, tiny SM) cg → bH + → btb(bar) Top w/ two p T b-jets (H + ) Ghosh, WSH, Modak, 1912,10613 (PRL pending) √ HKM, PLB’18 enhanced George W.S. Hou (NTU) Colloquium 09/22/20 26 Flav/HIG

Example: take CMS “ A → tt ( bar ) ” hint Decadal CMS JHEP’20 35.6 fb − 1 (2016 data) “ a signal-like excess for the pseudoscalar hypotheses (largest) at 400 GeV, Γ tot = 4% , 3.5 σ local (1.9 σ LEE) ” “ multiple testing ” Single-state analysis / Custodial A , H + Consistent with ρ tt = 1.1 , ρ tc = 0.9 ! • H Could be due to H if ρ tt imaginary . • WSH, Kohda, Modak, PLB’19 N.B. A near-perfect (Yukawa’s a bit large) scenario now being checked by Kumar ( flavor ) and Jain ( collider ) . ATLAS and Full Dataset to come ! George W.S. Hou (NTU) Colloquium 09/22/20 27 Flav/HIG