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Outlook: Higgs, SUSY, flavor. Ken-ichi Hikasa (Tohoku U.). Fourth Workshop, Origin of Mass and SUSY March 8, 2006, Epochal Tsukuba. Apology. This is not designed to be a summary talk … , so no reference to most of the talks. Standard Model. SM = GHY. Three elements G: gauge H: Higgs
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Outlook:Higgs, SUSY, flavor Ken-ichi Hikasa (Tohoku U.) Fourth Workshop, Origin of Mass and SUSY March 8, 2006, Epochal Tsukuba
Apology This is not designed to be a summary talk…, so no reference to most of the talks
SM = GHY • Three elements • G: gauge • H: Higgs • Y: Yukawa
SM = GHY • Three elements • G: gauge Dm • H: Higgs • Y: Yukawa • All gauge interactions from Dm = m + ig Am Universality: unique coupling, blindness to generations
SM = GHY • Three elements • G: gauge • H: Higgs l j4 • Y: Yukawa • Symmetry breaking, W,Z masses • Higgs mass term m2: only dimensional parameter in SM (classically) sets the weak scale
SM = GHY • Three elements • G: gauge • H: Higgs • Y: Yukawa y f fj • Fermion couplings to Higgs field • give masses to quarks/leptons
SM = GHY • Three elements • G: gauge Dm • H: Higgs • Y: Yukawa • Only interaction experimentally confirmed: 2/3 of SM still to be tested
SM = GHY • Three elements • G: gauge • H: Higgs • Y: Yukawa yij fi fjj • No ‘universality’: origin of flavor difference and mixing • Most # of parameters in SM
u2 d2 u1 d1 Generation mixing If no Yukawa coupling, generation labels has no meaning
u2 d2 u1 d1 Generation mixing Charged current interactions connects ups and downs W±
u2 c u1 u d2 s d1 d Generation mixing Yukawa couplings breaks the generation symmetry
Generation mixing Mismatch of ups and downs gives the Cabibbo mixing u2 c u1 u d2 W s d1 C d
Leptons If the neutrinos were massless… n2 n1 2 m 1 e
Leptons Neutrino eigenstates can be defined only by charged current and the lepton flavors are conserved n2 nm n1 ne 2 m 1 e
Neutrino mass (side remark) • In SM, n is made to be massless • Quark-lepton correspondence • Naturally expect nR & Yukawa • nR : gauge blind particle (hard to see) • Ultratiny mass suggests different origin • Important question: Dirac or Majorana?
DIweak = ½ Rule • Quark/lepton masses have to be DIweak = ½ • W, Z masses can have any DIweak • Precision measurements: experimental evidence for DIweak = ½ dominance
DIweak = ½ Rule r=1 to high precision doublet vev dominance
80.5 80.4 80.3 MW (GeV) 150 175 200 Mtop (GeV) Indirect Higgs limit
Direct Higgs searches • Still a long way to go, but worth pursueing
MSSM/two doublet • Large tan b region started to be excluded at Tevatron A0 t+t-
Beyond SM Standard Model is not the final story
(Observational)reasons we need FBSM • Gravity • Dark Matter • Dark Energy • Baryon asymmetry • CMB • Neutrino mass
(Theoretical)reasons we need FBSM • No strong CP violation • Hierarchy problem? • Too many parameters? • Unification of gravity
Where to seek for FBSM • New particles • Energy frontier • Faint interactions (can be light) • Forbidden processes • baryon # violation • lepton # violation • lepton flavor violation (seen in n oscillations, but very small) • Suppressed processes
Weak interaction processes • Superallowed t b, c s • CKM suppressed (tree-allowed but small) b c, u; s u • GIM suppressed (tree-forbidden) FCNC b s, d; s d Good place to look for new physics
Supersymmetry Raison d’être aka excuse: Unique nontrivial extension of the Poincaré group (= Einstein’s relativity) Motivation @ weak scale: Stabilize Fermi-Planck hierarchy by cancelling loop corrections
Extra Dimensions Raison d’être aka excuse: Superstrings require 10 spacetime dimensions for consistency Motivation @ weak scale: (Originally) trading the Fermi-Planck hierarchy for large extra-dim size More recently, branes, Randall-Sundrum hierarchy, …
Extra Dimensions All SM interactions are nonrenormalizable for D>5 Couplings tend to blow up above weak scale: Strong-coupling phenomena at TeV (Technicolor-type physics) Higgsless models: Heavy W,Z recurrences should appear
MSSM • Many parameters (>100) • New sources of flavor structure • Sfermion masses (left and right) • LR mixing (A term) • New sources of CP violation • LSP neutralino: good DM candidate
D-squark mass matrix One new source of flavor mixing
D-squark mass matrix Chiral substructure of sfermion mass
Vast parameter space • Most regions contradict with neutral Kaon mixing • mSUGRA, CMSSM: tiny regions in the parameter space • Useful as a guideline • Should not trust too much
Varied phenomenology • Different mass patterns • Generally: colored > noncolored • Split SUSY: scalars > gauginos • Focus point: light higgsinos • Interesting alternatives • Gauge mediation: stau LSP • Anomaly mediation: light wino • R parity violation: exotic resonances
Rare b decays • In SM, b s is much more suppressed than b c good place for new physics • b-s sfermion mixing can contribute to CP asymmetry
Sign of SUSY contributions • Extra contribution to sL Same sign deviation for B fK and h’K • New mixing of sR Opposite sign deviation for B fK and h’K
Consequence of possible deviation • If both fK and h’K deviates in the same direction, new physics are in the left-handed sector (the data are old) Endo, Mishima, Yamaguchi
Lepton-flavor violation • Neutrino mass mixing: way too small effect on charged lepton FV • Supersymmetry: slepton mass matrix gives new LFV source • GUT: quark mixing lepton mixing • Right-handed n new mixing source • Observable effect expected in t mg, m eg etc.
Conclusions • Tevatron has plunged into new luminosity frontier • SM Higgs: important target to pursue • MSSM/Two doublet: already started to constrain parameter space • Supersymmetry, XD, etc: Don’t wait for LHC
Conclusions (cont’d) • B factories • Very rich physics output • Good measurements of all 3 angles • Hint of new physics?? • t LFV: unique place to seek for FBSM • Kaon physics • should not be discontinued
Future LHC, ILC K physics B physics
One final remark ‘Mass-origin’ priority-area grant ends in one month, but We are still on the way!