Outlook: Higgs, SUSY, flavor

Ken-ichi Hikasa (Tohoku U.)

Fourth Workshop, Origin of Mass and SUSYMarch 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 Y: Yukawa

SM = GHY

Three elements G: gauge D

H: Higgs Y: Yukawa

All gauge interactions from D = + ig A

Universality: unique coupling, blindness to generations

SM = GHY Three elements

G: gauge H: Higgs 4

Y: Yukawa

Symmetry breaking, W,Z masses Higgs mass term 2: only dimensional

parameter in SM (classically) sets the weak scale

SM = GHY

Three elements G: gauge H: Higgs Y: Yukawa y f f

Fermion couplings to Higgs field give masses to quarks/leptons

SM = GHY

Three elements G: gauge D

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 fj

No ‘universality’: origin of flavor difference and mixing

Most # of parameters in SM

Generation mixing

u1

u2

d1

d2

If no Yukawa coupling, generation labels has no meaning

Generation mixing

u1

u2

d1

d2

Charged current interactions connects ups and downs

W±

Generation mixing

Yukawa couplings breaks the generation symmetry

u1

u2

d1

d2

u

c

d

s

Generation mixing

Mismatch of ups and downs gives the Cabibbo mixing

u1

u2

d1

d2

u

c

d

s

C

W

Leptons

If the neutrinos were massless…

1

2

1

2

e

Leptons

Neutrino eigenstates can be defined only by charged currentand the lepton flavors are conserved

1

2

1

2

e

e

Neutrino mass (side remark)

In SM, is made to be massless Quark-lepton correspondence

Naturally expect R & Yukawa R : gauge blind particle (hard to see)

Ultratiny mass suggests different origin Important question: Dirac or Majorana?

Higgs sector

Iweak = ½ Rule

Quark/lepton masses have to be Iweak = ½ W, Z masses can have any Iweak

Precision measurements: experimental evidence for Iweak = ½ dominance

Iweak = ½ Rule

=1 to high precision doublet vev dominance

Indirect Higgs limit

Mtop (GeV)

MW

(GeV

)

150 175 200

80.5

80.4

80.3

Direct Higgs searches Still a long way to go, but worth pursueing

MSSM implies light Higgs

MSSM/two doublet Large tan region started to be excluded at Tevatron

A0 +-

Beyond SM

Standard Model is not the final story

(Observational) reasons we need BSM

Gravity Dark Matter Dark Energy Baryon asymmetry CMB Neutrino mass

(Theoretical) reasons we need BSM

No strong CP violation Hierarchy problem? Too many parameters? Unification of gravity

Where to seek for BSM New particles

Energy frontier Faint interactions (can be light)

Forbidden processes baryon # violation lepton # violation lepton flavor violation (seen in oscillations, but very small)

Suppressed processes

Weak interaction processes

Superallowedt b, c s

CKM suppressed (tree-allowed but small) b c, u; s u

GIM suppressed (tree-forbidden) FCNC b s, d; s dGood place to look for new physics

BSM Scenarios

SupersymmetryRaison 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 DimensionsRaison 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

And many others

Minimal Supersymmetric Standard Model

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

2 2 2

2 2 2

2 2 2

dd ds db

sd ss sb

bd bs bb

m m m

m m m

m m m

One new source of flavor mixing

D-squark mass matrix

2 2 2

2 2 2

2 2 2

dd ds db

sd ss sb

bd bs bb

m m m

m m m

m m m

Chiral substructure of sfermion mass

2 2

2 2bLsL bLsR

bRsL bRsR

m m

m m

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

Dark Matter

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 asym

metry

New physics effects on b s

Sign of SUSY contributions

Extra contribution to sL

Same sign deviation for B K and ’K New mixing of sR

Opposite sign deviation for B K and ’K

Consequence of possible deviation

If both K and ’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 new mixing source Observable effect expected in , e etc.

Conclusions

Conclusions

Tevatron has plunged into new luminosity frontier SM Higgs: important target to pursue MSSM/Two doublet: already started to constrai

n 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?? LFV: unique place to seek for BSM

Kaon physics should not be discontinued

Future

2 2 2

2 2 2

2 2 2

dd ds db

sd ss sb

bd bs bb

m m m

m m m

m m m

LHC, ILC

B physics

K physics

One final remark

‘Mass-origin’ priority-area grant ends in one month,

but

We are still on the way!