Prospect after discoveries of Higgs/SUSY

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Prospect after discoveries of Higgs/SUSY

• Yasuhiro Okada (KEK)
• Discoveries of Higgs and Supersymmetry to
  Pioneer Particle Physics in the 21st Century
• November 25, 2005, Univ. of Tokyo

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(1) Higgs Physics

• Finding the mass-generation mechanism for gauge
  bosons, quarks and leptons the most urgent
  question of the present particle physics.
• Discovery of the Higgs boson is the first step.
• The answer is most probably related to what is
  physics beyond the standard model. The
  electroweak symmetry breaking requires dynamics
  beyond the SU(3)xSU(2)xU(1) gauge interactions.
  

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How we have come to understand the strong
interaction.
Structure of a nucleus (proton / neutron)
Discovery of Yukawa meson
Quark model
QCD
Discovery of the Higgs boson is similar to
discovery of the Yukawa meson in understanding
the weak interaction.
Weak interaction
Higgs mechanism
Dynamics behind the EW symmetry breaking
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A Higgs sector is unknown How many Higgs
bosons? (is there any?) What is the mass ? What
is SU(2) representation?
Even if one Higgs doublet model is a good
description,
What is f? What physics determines m2? What
physics determines l?
Different scenarios provides different
answers. SUSY, String Theory Composite model,
Little Higgs model TeV scale extra dimension
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Composite model
SUSY GUT
Extra dimension
Various new physics signals are expected in the
TeV region, depending on different signals.
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Higgs mass
Large Higgs mass ? Large self-coupling ? Strong
dynamics
If we require that the SM is valid up to 1019
GeV,
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Two interesting cases
(2) High mass Higgs boson (gt300 GeV)
(1) Low mass Higgs boson (lt 130 GeV)
M.Peskin and J.Wells
SUSY
(mhlt 135 GeV for MSSM)
or
Higgs potential is generated at low energy scale
(lt 0(10) TeV ) Ex. Pseudo Nambu-Goldstone boson
Something is needed to be consistent with the EW
precision data.
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Higgs coupling
LHC 0(10) for ratio of the coupling
constants
ILC A few for absolute values of various
coupling
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Indirect constraint on the heavy Higgs boson mass
in MSSM
Direct search at LHC
Direct search at 1TeV LC
ACFA Higgs WG S. Kiyoura, et al
ACFA report
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SUSY loop contributions to the hbb Yukawa
coupling
B(h-gtbb)/B(h-gttt) nomalized by SM value
B(h-gtbb)/B(h-gttt) is sensitive to the SUSY loop
correction to the bottom Yukawa coupling for
a large tanb region.
LC
LHC
K.S.Babu, C.Kolda M.Carena, D.Garcia,
U.Nierste, C.E.M.Wagner
J.Guasch, W.Hollik,S.Penaranda
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Higgs self-coupling measurement
Access to the Higgs potential. Precision at 1/ab
for 120 GeV Higgs boson 20 for 500GeV ILC
10 for 1 TeV ILC
Y.Yasui, et al, LCWS 02
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Electroweak baryogenesis and Higgs potential
The Higgs potential at zero temperature is also
modified. gt Self coupling measurement
Model with dim 6 potential
2HDM
S.Kaenmura, Y. Okada, E.Senaha
C.Grojean,G.Servant, J.D.Wells
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(2) Supersymmetry

• Supersymmetry is a revolution of physics similar
  to relativity, if it is found.
• SUSY provides a coherent picture of particle
  physics and cosmology

SUSY GUT gt Gauge coupling unification SUSY R
parity gt Dark matter SUSY Seesaw neutrino gt
Leptogenesis
(Baryon number of the Universe)
After we confirm the supersymmetry, whether these
ideas are realized could be central issues.
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SUSY and GUT
LHC/LC combined analysis
SUSY breaking scenario
G.A.Blair, W.Porod,and P.M.Zerwas
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Dark matter
ALCPG cosmology subgroup
SUSY mass and coupling measurements gt
Identification of dark matter
PLANCK
WMAP
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SUSY Seesaw model
Large Lepton flavor violation processes are
expected.
m-gteg in SU(5) SUSY GUT with seesaw neutrino
Slepton flavor mixing
J.Hisano, M.M.Nojiri, Y.Shimizu, M.Tanaka
T.Goto,Y.Shimizu,T.Shindo,M.Tanaka and Y.Okada.
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Conclusions

• Discovery of the Higgs boson is the first step to
  understand the dynamics of the electroweak
  symmetry breaking.
• Measurements of the Higgs coupling constants can
  provide hints to new physics.
• SUSY, if it exists, has far-reaching consequences
  in particle physics and cosmology.