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10 March 2013Aspen Winter School

Higgs Quo Vadis

Department of Physics, School of Science, and International Center for Elementary Particle Physics, The University of Tokyo Chair: High Energy Physics Committee of Japan Sachio Komamiya

The Rising Sun of the Linear Collider

There was a revolution in particle physics ！ The 1974 November Revolution

Discovery of J/ψ （ charm quark ）

e+e- →ψ SLAC Richter et al.

J→ e+e- 　

BNL 　 Ting（丁） et al.

J/ψ ＝ｃｃ　 bound stateIt becomes evident even for experimental physicists that quarks and leptons are the elementary particles of the same level. ⇒ base of The Standard Model

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Gauge Bosons

Higgs BosonQ

uark

sLe

pton

s

Eve of the Revolution

ICHEP 1974 Summer Fermilab

B.Richter

J.Ellis

4

Until 4th July 2012, for more than 20 years, we keep agitating that a Revolution in the field of particle physics is inevitable.

⇒ Discovery of “Higgs Boson” = The July revolution has started

⇒ This is just a start of an enormous revolutionary era overwhelming the Standard Model = the Ancien Regime.

Elementary Higgs BosonSupersymmetry ?

Composite Higgs BosonTechnicolor etc. ???

Light Higgs Boson

Heavy Higgs Boson

Higgs Boson mass is responsible for a big branching in the particle physics history

～ 125 GeV Higgs Boson is categorized as a light Higgs Boson

Supersymmetry (SUSY) solves Supersymmetry (SUSY) solves miltiple problemsmiltiple problems

FermionsFermions BosonsBosons

electron spin =1/2

selectronspin = 0

Supersymmetric partner of electron

Wave function of spin1/2 Fermion

・ ・ The lightest SUSY particle is a good candidate of the Dark MatterThe lightest SUSY particle is a good candidate of the Dark Matter　　　　　　　　　　　　⇒ ⇒ We gain the understanding of the structure of the We gain the understanding of the structure of the

universeuniverse・　・　 SUSY is a space-time symmetrySUSY is a space-time symmetry　　　　　　　　　　　　 It plays a crucial role for the unification of 3 forces with It plays a crucial role for the unification of 3 forces with

gravitygravity Number of extra-dimensions in the string theory is Number of extra-dimensions in the string theory is

determineddetermined

+f f~

h h h h_

・　 Stabilization of Higgs Boson Mass due to a cancellation　　　　　　⇒ Numbers of Fermion and Boson fields are identical

Investigation of Higgs boson (scalar particle has the same quantum numbers as for the vacuum) can be the zeroth step to understand inflation of the universe and dark energy.

From Higgs to the Universe

e

e+

-

　Z

Ｚ

H bb

μ ＋ μ-

-

Electron-positron collider

Electron and positrons are pont-like elementary particles

⇒ Clean environment Process is simple Prediction ：　 O(0.1%)

Ex. Higgs Boson

p

pbb-

g

g

t

Proton-Proton Collider

H

hadrons

hadrons

Proton is a composite particle 　 ⇒　　Complicated process NNLO 　 O(10%)

High radiation 　 High event rate

⇒ need a high tech detector

pp-collisionpp-collision 　ｖｓ　　ｖｓ　 ee++ee−− collisioncollision 8

Propaganda plot of LHC for MEXT

LHC overlooks new phenomena including Higgs Boson and SUSY

Actual situation would be ……..

LHC overlooks new phenomena including Higgs Boson and SUSY

Since LHC physicists are excellent

LHC overlooks new phenomena including Higgs Boson and SUSY

Story of Top Quark and Higgs Boson

From precise electro-weak measurements at LEP, top mass was predicted

Precise Measurement of Top mass at the TEVATRON

Higgs mass is restricted into a narrow mass range using precise top mass and LEP/SLC electro-weak data 　　 114 GeV <MH< 160 GeV

Discovery to Top

Discovery of “Higgs” at LHC

Precise measurements of Higgs properties at ILC

top

Higgs

Z ZZZ

~

Importance of interplay between hadron and e+e- colliders

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Limit of High Energy Circular Limit of High Energy Circular e+e- Colliderse+e- Colliders

Reaction is simple, experiment is clean 　　　 but… 　　　 Electron 　 and positrons

loose energy due to synchrotron radiation 　　　　　　　　　　　

Energy loss per trun ΔE is given by

　　　 ΔE ∝ （ E/m ）４ /Ｒ

E ： particle energy 　　　　　　　　 ｍ： particle mass　　Ｒ： radius

Like a bankruptcy by loan interest 　　　　　　　　

E, m

Recover the energy loss and obtain higher collision energy

（１） Use heavier particle (proton mass/electron mass ＝ 1800 ）⇒ LHC

（２）　 Larger radius 　 ⇒　ＬＥＰ（２７ｋｍ）　⇒　large radius

２Ｒ

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Electron Positron Linear Collider is Electron Positron Linear Collider is inevitableinevitable

Straight beam line ⇒ 　 No synchrotron radiation 　（ Linear Collider ）

e+

e-

Electrons are accelerated from one side positon from the other side. Collide the beams at the center

Reduce construction cost ⇒ 　 High acceleration gradient Reduce running cost (electric power) ⇒ 　 Squeeze the beam size as small as possible at the interaction point 　　　⇒　round beam is unstable ⇒ 　 very flat beam

Large radius R 　 ⇒　 Ultimate radius R=∞ 　！　

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~ ３0 km

~ 1km

e- e+

～ 30 km

Damping Ring

SC Accelerator

Detector

International　Linear　ColliderInternational　Linear　Collider ：Ｆ１：Ｆ１ --machine　　machine　　

Technical　Design　Report　has　been　Technical　Design　Report　has　been　issued　end　issued　end　 ２０１２２０１２

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Tunnel design for Mountain Range site

TDR design of ILCfor Ecm = 500 GeV

ILC

σ (

fb)

# ev

ents

for

L=50

0 fb

-1

LHCTevatron LEP

Cross Sectionse+e− cross sections

√s (GeV)

Higgs BosonHiggs Boson　　

ILC in the first phase is the Higgs Boson FactoryILC in the first phase is the Higgs Boson Factory

O(10 ) such events will be collected and studied.O(10 ) such events will be collected and studied.

Origin of mass Structure of the ‘vacuum`.Origin of mass Structure of the ‘vacuum`.

Precise measurement of Higgs Boson ⇒ Deduce Principal Low in the Nature

e e Z + H e e + b b -++ --

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Recoil Mass MeasurementReconstruct Zl+l−independent of Higgs decaysensitive to invisible Higgs decays

gHZZ

ILC TDR, √s=250 GeV, L=250 fb−1

Model-independent,absolute measurements(Ze+e−,μ+μ− combined):

ΔmH ≤ 32 MeVσZH ≤ 2.5%gHZZ ≤ 1.2%

Gauss. width ≈ 650 MeV

=560 MeV 330 MeV

beam energyspread

detectorresolution

Higgs Measurements at ILC (1)

ILC TDR, mH=125 GeV, BRs from LHC HXSWG assumed.

250 GeV~Higgs-strahlung

350 GeV~WW fusion

Higgs Measurements at ILC (2)

ILC TDR, mH=125 GeV, BRs from LHC HXSWG assumed.Higgs is reconstructed in the hbb mode only.

H

H

H

H

t

t

H

500 GeV~Top Yukawa Coupling

500 GeV~Higgs Self-Coupling

Higgs Couplings at ILC

Measurement of σ×BR Input to global fit Extract Higgs couplingsExploit LHC / ILC synergy. M. Peskin hep-ph 1207.2516

Deviations from SM prediction is expected to be small O(%) level

t

t

H

250 GeV~Higgs BR viaHiggs-strahlung

350 GeV~Higgs BR viaWW fusion

500 GeV~Top YukawaCoupling

M. Peskin

LHC 14 TeV 300 fb-1

ILC 250 GeV 250 fb-1 500 GeV 500 fb-1 1TeV 1000fb-1

LHC 14 TeV 300 fb-1

ILC 250 GeV 250 fb-1 500 GeV 500 fb-1 1TeV 1000fb-1

COBE 1990 　　 Angular resolution = 10° Temperature fluctuation 10-5K

WMAP 2003 Angular resolution = 10’ Age of the Universe =13.69±0.13 Gyr Polarization measurement

Impact of Precise Impact of Precise MeasurementMeasurement A. WagnerA. Wagner

ILC Detector R&D

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HCAL

ECAL

TPC

Beam line

VTXSITFTD

ETD

SET

Return Yoke

Coil

Forwardcomponents

~15 m

• Vertex Detector: pixel detectors & low material budget

• Time Projection Chamber: high resolution & low material budget, MPGD readout

• Calorimeters: high granularity sensors, 5x5mm2 (ECAL) 、 3x3cm2 (HCAL)

Sensor Size ILC ATLAS Ratio

Vertex 5×5 mm2 400×50 mm2 x800

Tracker 1×6 mm2 13 mm2 x2.2

ECAL 5×5 mm2 (Si) 39×39 mm2 x61

Particle Flow AlgorithmCharged particles Tracker,Photons ECAL, Neutral Hadrons HCALSeparate calorimeter clusters at particle leveluse best energy measurement for each particle.offers unprecedented jet energy resolution

State-of-the-art detectors can be designed for ILC

Tanabe, ICEPP

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背振Sefuri

北上Kitakami

Possibility of Japan to be a host of ILC

Some facts to believeJapan to host ILC, if we work very hard for the next few years.1) Discovery of “Higgs Boson” at LHC2) TDR of ILC project will be issued NOW.3) CERN is expected to work on LHC upgrade Support from international community4) Supports of Political and Industrial sectors ・ Advanced Accelerator Association of Japan5) Started site studies with dedicated funding6) Agreement in the HEP community ・ Report from subcommittee of future HEP projects of Japan (March 2012)　 ・ Phased Excecution of ILC （ October 2012)　

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A Proposal for a Phased Execution of the International Linear Collider ProjectThe Japan Association of High Energy Physicists (JAHEP) endorsed the document on 18 October 2012

ILC shall be constructed in Japan as a global project based on agreement and participation by the international community.

Physics : Precision study of “Higgs Boson” , top quark, “dark matter” particles, and Higgs self-couplings,

Scenario : Start with a Higgs Boson Factory ~250 GeV. Upgraded in stages up to a center-of-mass energy of ~500 GeV, which is the baseline energy of the overall project. Technical extendability to a 1 TeV region shall be secured.

Japan covers 50% of the expenses (construction) of the overall project of a 500 GeV machine. The actual contributions, however, should be left to negotiations among the governments.

Advanced Accelerator Association of Japan (AAA) 　

Industry: 85 companies （ Mitsubishi HI 、 Toshiba 、 Hitachi 、 Mitsubishi Electric 、 Kyoto Ceramic et al. ） Academy: ３８ institutes （ KEK ， Tokyo 、 Kyoto 、 Tohoku, Kyushu, RIKEN, JAEA et al.)

as of December 2011

Industry: 85 companies （ Mitsubishi HI 、 Toshiba 、 Hitachi 、 Mitsubishi Electric 、 Kyoto Ceramic et al. ） Academy: ３８ institutes （ KEK ， Tokyo 、 Kyoto 、 Tohoku, Kyushu, RIKEN, JAEA et al.)

as of December 2011

Union of Diet members to promote a construction of international laboratory for LC

31st July 2008 established a suprapartisan ILC supporters

(July 2008 〜 )President Kaoru Yosano 　　Deputy Yukio HatoyamaSecretary-General Take Kawamura、 Yoshihiko NodaDirector 　 Norihisa Tamura 　　　　 Masamitsu Naito

Akihito Ohhata 、 Koji Omi 、 Ikuo Kamei, Takeo Kawamura, Tetsuo Saito, Yoshiaki Takagi, Norihiko Tamura, Masamitsu Naito, Yoshihiko Noda, Yukio Hatoyama 、 Fumuhiro Himori, Kosuke Hori, Eisuke Mori, Kaoru Yosano 、 Hidekatsu Yoshii

proposers

December 2011 at AAA symposium

Supreme advisor 　 Kaoru YosanoPresident Emeritus Masatoshi KoshibaPresident Takashi Nishioka (Mitsubishi HI ）Trustee Atsuto Suzuki （ KEK) 〃　　 Akira Maru （ Hitachi ）、 〃 Yoshiaki Nakaya （ Mitsubishi Electric ）　 〃　 　　　 Yasuji Igarashi （ Toshiba ）、 〃 Akira Noda （ Kyoto University ）　 〃　　　　 Keijiro Minami （ Kyoto ceramic ）Auditor Sachio Komamiya (University of Tokyo ）

Supreme advisor 　 Kaoru YosanoPresident Emeritus Masatoshi KoshibaPresident Takashi Nishioka (Mitsubishi HI ）Trustee Atsuto Suzuki （ KEK) 〃　　 Akira Maru （ Hitachi ）、 〃 Yoshiaki Nakaya （ Mitsubishi Electric ）　 〃　 　　　 Yasuji Igarashi （ Toshiba ）、 〃 Akira Noda （ Kyoto University ）　 〃　　　　 Keijiro Minami （ Kyoto ceramic ）Auditor Sachio Komamiya (University of Tokyo ）

New Officers (October 2011 〜 )Supreme advisor 　 Kaoru YosanoPresident 　　　　 Yukio HatoyamaActing president Takeo KawamuraSecretary-general 　 Tatsuo KawabataDeputy 　 Tatsu ShionoyaDupty President 　　 Tetsuo Saito President of bureau Norihisa TamuraDirector of bureau 　 Keisuke TsumuraDeputy Takeshi Kai

AAA homepage http://aaa-sentan.org

June 2008 established an industry-academy collaboration

Renewed on 1st Feb 2013

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History of International LC Community1980s LC accelerator R&D starts at DESY, KEK, SLAC , CERN, …1990s 5 different designs: TESLA , S-band, C-band, X-band, CLIC1998 World-wide-studies of physics and detector for LCs was established2003 ILC Steering Committee (ILCSC) formed 2004 Selected superconducting RF for the main linac2005 Global Design Effort (GDE) formed (Barry Barish)2007 Reference Design Report2009 LOI process validated two detector concepts (ILD and SiD) 2012 Technical Design Report2013 Feb. LCC formed (Lyn Evans)2013 June TDR review will be completed

The Jump-Start Scenario (Very optimistic but not impossible) 2013 July Site evaluation by scientists will complete in Japan 2013 fall New organization within Japanese government is expected to be formed and in preparation to bid to host the ILC2014-15 Intergovernmental negotiation Linear Collider Collaboration (Lyn Evans and ILC sector) continue to refine the design and organization of the global lab for ILC2015 International Review of the ILC project (LHC physics @13-14 TeV) 2015-16 Construction starts2026-27 Commissioning of the ILC machine

Europe Asia Americas

DORIS

PETRA

HERA

ISR

SppS

LEP/LHC

TEVATRON

TRISTAN

SPEAR

SLCPEP

ISABELLE RHIC⇒

SSC

Energy frontier Colliders

Europe Asia Americas

DORIS

PETRA

HERA

ISR

SppS

LEP/LHC

TEVATRON

TRISTAN

SPEAR

SLCPEP

ISABELLE

SSC

Energy Frontier CollidersFuture Colliders must be planned and constructed by

global efforts

ILC

Lepto

n

Qu

ark

ee

Lepton CPLepton CP AsymmetryAsymmetry Beyond Standard PhysicsBeyond Standard Physics

KEK-BKEK-B

LHCLHC

J-PARCJ-PARC

Power-Upgrade

[Origin of Force]

Higgs Particle [Origin of Mass]

Quest for Quest for Birth-EvolutionBirth-Evolution

of Universe of Universe

Quest for UnifyingQuest for UnifyingMatter and Force Matter and Force

Super-KEKB

International Linear Collider（ ILC ）

Quark CP Quark CP AsymmetryAsymmetry

[Origin of Matter]

Quest for 6 QuarksQuest for 6 QuarksQuest for NeutrinosQuest for Neutrinos

Scientific ActivitiesTechnology InnovationEncouraging Human

Resources

KEK DG is keep showing this ugly slide

Lepto

n

Qu

ark

ee

Lepton CPLepton CP AsymmetryAsymmetry Beyond Standard PhysicsBeyond Standard Physics

KEK-BKEK-B

LHCLHC

J-PARCJ-PARC

Power-Upgrade

[Origin of Force]

Higgs Particle [Origin of Mass]

Quest for Quest for Birth-EvolutionBirth-Evolution

of Universe of Universe

Quest for UnifyingQuest for UnifyingMatter and Force Matter and Force

Super-KEKB

International Linear Collider（ ILC ）

Quark CP Quark CP AsymmetryAsymmetry

[Origin of Matter]

Quest for 6 QuarksQuest for 6 QuarksQuest for NeutrinosQuest for Neutrinos

Scientific ActivitiesTechnology InnovationEncouraging Human

Resources

All roads lead to ILC

Higgs Branching Ratios

Supersymmetry Supersymmetry (SUSY)(SUSY)

Lept

ons

and

Qua

rks

Ordinary particles

Gauge bosons

Higgs boson

Ordinary particlesGauge bosons

SUSY partners

Higgs bosons

Gauginos

Dark Matter Candidates

Higgs and SUSY are undiscovered

Lept

ons

and

Qua

rks

Sca

lar

Fer

mio

ns

Higgsinos

・ ・ Every Elementary Particle has SUSY partner, Every Elementary Particle has SUSY partner, their masses their masses 　＜　＜ TeVTeV

⇒ ⇒ The value of the SUSY discovery is that for the The value of the SUSY discovery is that for the Anti-particlesAnti-particles

～

Power of electron polarization at ILCPower of electron polarization at ILC

Unpolarized

Scalar muon production

Background signalPolarized (90% e-R)

μ

μ

beam

θacop μ

μR~

ILCILC budget (German budget (German version)version)

（（ for a host country/regiofor a host country/regionn ））

Bier　vom　Fass

Euro/Yen/Dollar per person per year

~10 years

Eine Wurst mit Sauerkraut

Since cost review of TDR is not completed I cannot tell you the price now.

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Fingerprinting BSMSinglet Mixing

+5%

0%

-5%

-10%

-15%

+10%

+15%

Hig

gs

Co

up

lin

g D

ev

iati

on c τ b t W Z HΓh

+5%

0%

-5%

-10%

-15%

+10%

+15%

Hig

gs

Co

up

lin

g D

ev

iati

on c τ b t W Z HΓh

MSSM / Type II 2HDM

Composite Higgs

+5%

0%

-5%

-10%

-15%

+10%

+15%

Hig

gs

Co

up

lin

g D

ev

iati

on c τ b t W Z HΓh

Electroweak Baryogenesis

+5%

0%

-5%

-10%

-15%

+10%

+15%

Hig

gs

Co

up

lin

g D

ev

iati

on c τ b t W Z HΓh

If you want to know more on Higgs at ILC, please read TDR volume 1

Coupling measurements at ILCCoupling measurements at ILCGauge Coupling

Yukawa coupling

Self-coupling Top Yukawa coupling

SUSY