ILC Project

Hitoshi Yamamoto

Tohoku University

New Higgs Working Group 8th Annual Meeting

Toyama, January 11, 2014

ILC (International Linear Collider)

500 GeV CM with 31 km → upgrade later to ~ 1TeV CM with 50 km IP beam size : 6 nm high, 500 nm wide 300 mm long (@500 GeV CM) Luminosity 1.8 x 1034 /cm2s (@500 GeV CM） First stage : 250 GeV Higgs Factory

e+ e- collider

ILC TDR Completion June 12, 2013

‘A World-wide Event – from design to reality’

Tokyo

Fermilab

Fermilab

CERN

4

LC Collaboration Director Lyn Evans

ILC accelerator Mike Harrison

ILC/CLIC Phys./Det. Hitoshi Yamamoto

CLIC accelerator Steinar Stapnes

LC Board Chair : Sachio Komamiya

Deputy Director Hitoshi Murayama

LCC (LC Collaboration)

New International LC Organization

In full operation since June, 2013

ILC Timeline Proposed by LCC

• 2013 - 2016 – Negotiations among governments – Accelerator detailed design, R&Ds for cost-effective production, site

study, CFS designs etc. – Prepare for the international lab.

• 2016 – 2018 – ‘Green-sign’ for the ILC construction to be given (in early 2016 ) – International agreement reached to go ahead with the ILC – Formation of the ILC lab. – Preparation for biddings etc.

• 2018 – Construction start (9 yrs)

• 2027 – Construction (500 GeV) complete, (and commissioning start) (250 GeV is slightly shorter)

ILC Physics

ILC features : cleanliness

■ Collision of two elementary particles proton + proton at LHC

Proton = 3 quarks + gluons

electron + positron at ILC

→ Signal is clearly seen without much noises

LHC ILC

All from Higgs

→ Theoretically clean (less theoretical uncertainties)

→ Trigger-less data taking

proton

quark

gluon

proton

electron positron

LHC

ILC

ILC features : control

■ Initial state of electron-positron interaction : Energy-momentum 4-vector is specified

Electron polarization (80%~90%) is specified

Positron polarization (60%) is optional (30% comes for free)

LHC ILC

Energy-momentum 4-vector → e.g. recoil mass analysis: tagged Higgs Higgs to ALL (including invisible final state)

H⇾gg

H⇾ZZ

Electron polarization

e+

e-

g,Z

(B,A0)

Specify the intermediate state

e.g. Right-handed e- turns off A0

Information on the gauge structure

of the final state

Increase rates

e.g. P- /P+ = -0.8/0.3 :

Increases the H production mode

s(nnH) by X 2.34 (=1.8 x1.3 )

Background rejection

Right-handed e- turns off W

e-

e+ W+

W-

e.g. acoplanar muon pair produciton such as smuon pair production

ILC @1 TeV

• At higher Ecm – W fusion dominant

– More Higgs

– New particles !

W fusion Higgsstrahlung

Luminosity each energy for ~3 years

• Good for Higgs self coupling

e+e- ⇾ nnHH

– Effect of irreducible diagrams less important

dl/l = 0.76 ds/s @ 1 TeV

(dl/l = 1.66 ds/s @500 GeV)

dl/l = 13% (2.5 ab-1 @ 1 TeV)

Higgs production

Higgs Reconstruction

At 250 GeV Recoil mass analysis dMH = 32 MeV (TDR)

At 500 GeV 2 jet events Main background = nnZ

ILC Luminosity Upgrade Options

• 250 GeV CM (Higgs factory)

– X4 luminosity @ 3E34/cm2s

– x2 Nbunch, x2 rep rate; 120 ⇾ 200 MW wall plug

• 500 GeV CM

– x2 luminosity @3.6E34/cm2s

– x2 Nbunch; 160 ⇾ 200 MW wall plug

• 1 TeV CM

– x1.4 luminosity @5E34/cm2s

– Aggressive beam params;

Same wall plug power

Measurement errors of Higgs Couplings (Snowmass study – Higgs WG)

• All assume generation universality, no BSM → Fit – LHC ranges : optimistic (sys.err: theory = 1/2, exp. N-1/2), pessimistic (no change)

• Apart from g, ILC is 1/3 ~ 1/10 of HL-LHC

• With luminosity upgrade, additional ~1/2

• ILC can measure model-independently w/o assumptions above.

Top Yukawa Coupling

Direct measurements

• Gtot to 5%

– Br(H ⇾ WW) & g(HWW) by e+e- ⇾ nnH

– Br(H ⇾ ZZ) & g(HZZ) by e+e- ⇾ HZ

• CP

– 3~4% (on mixing coeff) by HZ

• cross sestion and production/decay angles

– Or by H → tt (t polarization)

• a to 6゜ w/ ab-1 at 350 GeV

Higgs Width and CP

mt(msbar) to 100 MeV

Sensitivity to ttH coupling at threshold

Anomalous ttZ, tbW, ttg coup

Top

New Particle Search

LHC Difficulty when mass difference is small

ILC Good sensitivity up to kinematic limit for (essentially) any mass difference

pp ˜ 20 ˜ 3

0

Fermion Compositeness

ILC 500 GeV : e+ e- → ff

+ - : initial helicity

Z’ couplings to identify a model

MZ’ = 2 TeV MZ’ = 4 TeV

1000 fb-1 at 500 GeV P- = 0.8, P+ = 0.6

e+ e- → l+l-

Dark Matter

■ Lightest super particle (LSP) is the dark matter?

■ Key: can the theory with measured parameters explain the ‘measured’ relic density?

■ Creation and annihilation → relic density

■ Need to know processes contributing to LSP annihilation

Relic density estimation by LHC (red) and ILC(blue) (SUSY B’ model)

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Dark Matter

21

Origin of Neutrino Mass

Bilinear R-parity violation model ILC measurement is consistent with sinq23 by neutrino experiment ? → neutrino mass mechanism

ILC Accelerat or

ILC: How it works

Produce：electron source

Produce：Positron source

Accelerate：main linac

Align：damping ring

Focus：final focus System

Detect：high-res detectors

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• Low emittance : KEK ATF (Accelerator

Test Facility)

– Achieved the ILC goal.

• Small vertical beam size : KEK ATF2

– Goal = 37 nm, 65 nm achieved • Limit is in measurement. No basic problem seen.

• Stabilize the beam at nm scale: KEK ATF2

– Feedback system successful (FONT)

Align and Focus

• Principle of acceleration – Generate strong RF wave in a

cavity – Synchronize such that particle

is always accelerated forward

• ILC accelerating cavity – Superconducting (niobium) – 1.3 GHz (L band） – 9 cell, 1 m – Accelerting gradient

• Average 31.5 MV/m • 250 GeV/31.5 MeV = 8000

cavities needed → ８km (In reality 11 km/side）

Accelerate : Main LINAC

超電導加速空洞 (Ichiro cavity)

1 m

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• Accelerating cavity

– Spec: 31.5 MV/m ±(<20%)

– >80% yield achieved (RDR goal achieved)

• Cryomodule assembly

– Combine cavities from all over the world

• KEK S1-global successful

Main LINAC Achievements

ILC technology is now ‘ready’

ILC Det ect ors

ILC Detector Performances

■ Vertexing ~1/5 rbeampipe,1/50~1/1000 pixel size, ~1/10 resolution (wrt LHC)

■ Tracking ~1/6 material, ~1/10 resolution (wrt LHC)

■ Jet energy (quark reconstruction by PFA) 1000x granularity, ~1/2 resolution (wrt LHC)

sE /E = 0.3/ E(GeV)

(h bb ,cc ,t +t-)

(e+e- Zh + -X; incl. h nothing)

sIP = 5 10

psin3 / 2 q(mm)

s(1/ p) = 2 10-5(GeV-1)

Above performances achieved in realistic simulations based on actual detector R&Ds.

Impact parameter resolution

ILC

Belle ATLAS

LHCb

Alice

• Charged part icles – Use t rackers

• Neut ral part icles – Use calorimet ers

• Remove double-count ing of charged showers – Requires high granularit y

PFA (part icle f low algorit hm)

#ch ECAL HCAL

ILC (ILD) 100M 10M

LHC 76K(CMS) 10K(ATLAS)

X103 for ILC Need new technologies !

ILD

Jet energy resolution

Jet Energy (GeV)

Jet

Ene

rgy

Res

olu

tio

n s

/Eje

t (%

)

PFA simulation 0

0.05

0.1

0.15

0.2

0.25

0.3

E 50 100 150 200 250

ATLAS simulation

ALEPH measured

CDF measured

DREAM measured

General Considerations (1)

Calorimeters inside solenoid For good jet reconstruction (track-cluster matching)

Low mass for tracking&vertexing Thin silicon sensors

e.g. ~50 mm for pixel vertex detectors

Light support structures

e.g. advanced endplate for TPC

High granularity esp. for calorimeters&vertexing Fine-granularity calorimeter readout: new technologies

Silicon pad, SiPM, RPC, GEM etc.

State-of-the-art pixel technologies for vertexing

CMOS, FPCCD, DEPFET, SOI, 3D…

Front-end electronics embedded in/near the active area (cabling!)

General Considerations (2)

As hermetic as possible

Forward calorimetry/tracking important

Vertex detector as close as possible to beam

Limit: e+e- pair background

Low heat generation (cooling eats up material budget)

Low-power front-end electronics

Power pulsing

Turn off power during bunch train gap

Density of pairs near IP - High B field helps

- Worse for high ECM

Beam pipe

#bunch/train train length train gap duty factor

ILC 1312 727ms 200ms 0.36%

CLIC

• SiD

– High B field (5 Tesla)

– Small ECAL ID (p resolution)

– Small calorimeter volume • Finer ECAL granularity

– Silicon main tracker

• ILD

– Medium B field (3.5 Tesla)

– Large ECAL ID (cost) • Particle separation for PFA

– TPC for main tracker

Design St rat egies

Det ect or Hall and Push-Pull

Lucie Linssen, LCWS12 Arlington, Oct. 22 2012

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Japanese underground hall Design

Status of the ILC Mostly in Japan

International Supports

• Europe : ‘European Strategy’ (March 22, 2013)

– There is a strong scientific case for an electron-positron collider, complementary to the LHC, that can study the properties of the Higgs boson and other particles with unprecedented precision and whose energy can be upgraded … The initiative from the Japanese particle physics community to host the ILC in Japan is most welcome, and European groups are eager to participate. Europe looks forward to a proposal from Japan to discuss a possible participation.

• US : HEPAP facilities subpanel report (March 22, 2013)

– The initiative from the Japanese particle physics community to host the ILC in Japan is very welcome, and the U.S. particle physics community looks forward to a proposal from Japan to discuss possible participation.

– For the final US strategy, wait for the HEPAP subpanel (P5) report (March-May, 2014)

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32 Rebuilding true command tower functions that strongly advance science and technology policies

– …We will actively promote the critical fields of energy creation, energy conservation, energy storage, etc. as knowledge-concentrated national strategies - for example, our country should be able to play a leading role in creation of international centers for scientific innovations such as the ILC (the international linear collider) project which is a grand project in the field of particle physics.

92 Creation of globally top-class centers for research and development

– …We will significantly strengthen supports for universities and public research facilities that perform studies at levels above the intentional standards, such as significant expansion of WPIs and playing a leading role in creation of international centers for scientific innovations such as the ILC (the international linear collider construction) project which is a grand project in the field of particle physics.

39

Political support : LDP (Liberal Democratic Party : New Ruling Party) election platform

‘ILC’ appears twice explicitly

40

Press conference by

the MEXT minister Shimomura Jan 18, 2013

‘(On ILC) We would like to consider the

plan for the near future, while as the

government actively negotiating with

relevant countries in the first half of this

year … we are now studying the legal

framework.’

The Japanese government did start to talk to other governments (informally).

Science Council of Japan Report submitted : Sep 30, 2013

41

• …we fully acknowledge the necessity and academic value of an electron-positron collider that is complementary to the LHC.

• …the Science Council of Japan proposes that the Japanese government appropriate necessary fund to study various issues toward deciding the implementation of the ILC project, and intensively conduct examinations and studies for 2 to 3 years by a group including experts outside of the relevant field and related government offices.

• In parallel with the above study and examination, negotiations should be conducted with research laboratories and funding authorities of relevant countries and regions to clarify the issues such as the international cost sharing.

(Unofficial translation)

MEXT has requested ~$0.5M for the investigatory study which was approved on Dec 24, 2013 !

A Letter to the DOE Secretary from the Federation of Diet Members for the ILC

Jan 8, 2014

42

…

In Japan, for the first time ever, the government has allocated a budget for the coming Japanese fiscal year to investigate and examine the ILC itself… This has great significance in that the Japanese government has shown a vital interest in the ILC project.

…

The ultimate decision to host the ILC project rests with the Japanese government and the Diet. Both houses of the Diet are strongly in support of the ILC project.

We have reached the stage where we must now work together with the other government for the realization of the ILC. The Japanese government intends to perform concentrated investigations and address the major issues and arrive at a conclusion about hosting the ILC by the end of JFY 2015.

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The most important issue for the realization of the ILC is whether it can become a truly global project. For this purpose, the Japanese government is currently gathering information from abroad and is starting talks with the United States and European countries about forming a partnership.

…

All 3 have served as the MEXT minister

ILC Candidate Sites in Japan

• Kyushu

– Sefuri mountains

• Tohoku

– Kitakami mountains

‘ILC site evaluation committee’ (JAHEP) Co-chairs: Kawagoe, Yamamoto

evaluated them based on

1. Geology and other technical aspects

2. Socio-economic conditions

Selected the Tohoku Site (Aug 23, 2013)

Sefuri

Kitakami

Kitakami Site • Flexibility in positioning the 50 km route

• Shorter access tunnels

• Natural Drainage

• etc…

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Sefuri Site

０．５% tilt

ILC route vertical cross section

Kitakami

Sefuri

Matsuura River

Below sea level

~100m above sea level

Summary

• With the discovery of Higgs, the physics case for the ILC is now

stronger than ever

• ILC accelerator design is ‘ready’ with the completion of TDR

• The ILC detectors are pushing the state of the art of particle

detection technologies

• Japanese government is now negotiating with other governments

toward realization of a truly global ILC lab

• There are strong supports from the international scientific

community. (will they translate to real commitments?)

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Backups

Accelerating cavity Challenge：

How to obtain high gradient? • State-of-the-art at early 1990’s: 5 MV/m

• 35 MV/m → Accelerator length 1/7 → cost ~ 1/5

– Problem • Discharge

– Physical defects、inpurity (particles)

• Local heating – Around welded areas etc.

– R&D goal (Vertical test) • 2010 : 50% >35 MV/m by 2nd test

• 2012 : 90% >35 MV/m by 2nd test

– ILC specification • (vertical test) average 35 MV/m, < ±20%

• (operation) average 31.5 MV/m, < ±20%

Accelerate : Main LINAC

空洞の垂直テスト（KEK）

• Cavity : discharge and heating

– Production process • Systematic QC of niobium plates

• High-pressure water rinsing

• Electro-polishing

– Diagnosis • Exterior temperature measurements

• Kyoto-KEK camera

– Examine inside of cavity

• Silicone molding

• OST (Oscillating Superleak Transducer)

– Quench location finder

– Repair • Mini-grinder

– Grind inside of cavity

• Electro-polishing, rinsing

電解研磨装置（KEK）

京都・KEKカメラとそのイメージ

ミニ研磨機

Accelerate : Main LINAC

Positron Source

Challenge:

• Undulator

– Short period (1 cm), High B field (0.9 T), superconducting

• Rutherford Alleton (UK) and Cornell (USA)

– 1.75 m prototype successful

• Titanium target

– Radius 1 m, 100 m/s rotation in vacuum and B field

• Cockroft Lab. (UK)

– Life-size prototype made

Eddy current is OK

– Rotation seal in vacuum

~ OK

アンジュレータ試作機

チタン標的試作機

• Cavity system tests – TTF/FLASH (DESY)

• A small version of FLASH: European-XFEL(2014~)

• 6 cryomodules, ８cavities each (22.4 MV/m)

• ILC-like high-current beam（9mA) successful

– STF (Superconducting RF Test Facility, KEK) • STF 1 (done) : ２ Cryomodules, 4 cavities each

• S1 global (done) ：cavities from all over the world

• STF 2 (now)： Accelerating unit test

（actual acceleration）

– NML (New Meson Lab, Fermilab) • Project X (high –intensity proton beam）R&D

STF (KEK)

NML (Fermilab)

Accelerate : Main LINAC

Vertexing

By D. Dunnheim

Technology for the ILC is largely open.

FPCCD (Japanese Group)

• FPCCD (fine pixel CCD)

– 5 mm x 5 mm pixel (inner layers)

– Signal integrated over a whole train

– Fully-depleted • Reduce diffusion (thus occupancy)

– Operated at -40°C

FPCCD R&D Status

• 6 mm x 6 mm pixel works – Full well capacity is still to be

improved (>10000 e)

• Large prototype works – 12mm x 64 mm (~real one)

• Fe55 X-ray signal seen – w/ 2.5 MHz RO speed (goal :

10MHz)

• New readout ASICs being developed – AFFROC-1

• Neutron test done – being analysed

Main Tracker

• Silicon strips (SiD)

– Chip-on-sensor design (KPIX chip)

– Si-strip tracker is used also for ILD in intermediate, forward, and endcaps

• TPC (ILD)

– Readout methods • MicroMEGAS

• GEM

• Silicon pixel (InGrid)

InGrid chip : 55 μm pitch

KPIX chip on sensor

MicroMEGAS

GEM

Asian TPC Efforts

• Within LC-TPC collaboration

– Asia: Japan, China, Philippines

• GEM-TPC

– Double GEM (laser-etched)

• 100 mm thick, 140 mm pitch

– 1.2 mm x 5.4 mm readout pads • 5152 channels/module

– Readout electronics • (S-)ALTRO chip (originally for ALICE TPC)

– Tested on the ‘Large Prototype’ • w/ PCMAG from KEK brought to DESY

Large prototype endplate

GEM module

PCMAG

Asian GEMTPC Beam tests DESY T24 Beamline (Pe = 5 GeV)

• 2010 (Sep 1 – 16) – B = 1T – GEM model partition = 2 – Discharge problem

• 2012 (Nov 19 – Dec 18) – B = 0T, 1T – GEM module partition = 4

• To suppress discharge

– Protection circuits etc. – More region in area/angle of

beam

• Spatial resolutions: – Understood from 1st principles – ILD requirement is more or less

met

Calorimetry

• Mostly done within the framework of CALICE collaboration

Calorimeter Activities in Japan

• CALICE framework • Scintillator calorimeter

– ECAL • Strip : 2 x 5 x 45 mm3

• Read out by MPPC (Hamamatsu ~ SiPM)

– Beam tests done

• Silicon calorimeter – Testing Si sensors – Beam tests done

• Hybrid ECAL calorimeter – Si and Sci – Optimization simulation study

• Software – PFA by strips (Strip-splitting algorithm)

Strip-splitting algorithm works!

Beam Tests

• ECAL beamtests – DESY, July&Oct 2013 (Recent ones of many)

– 2 lyrs Sci ECAL + 7 kyrs Si ECAL

• Not a true ‘hybrid’

– Sci ECAL technological prototype

• Being prepared Beam test setup

Sci ECAL hit distribution Si ECAL 2-track event

Next: 電子、陽電子衝突

e+

e-

T. Yoshioka

Find the photons and remove them

T. Yoshioka

Identify the showers associated with charged tracks and remove them.

T. Yoshioka

Clean up the noise The rest: neutral hadrons

T. Yoshioka

KEK roadmaps

• 2007

– ILC at the top of the

pyramid

• 2013

– KEK will play a central role in creating an international preparatory group and will lead the effort on advanced R&D, the engineering design of the apparatus and facility, and the organizational design toward groundbreaking for the linear collider project to be hosted in Japan, within the framework of a global collaboration.

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JAHEP (Japan Association of High Energy Physicists)

• A report on large projects (March 2012)

– On ILC: Should a new particle such as a Higgs boson with a mass below

approximately 1~TeV be confirmed at LHC, Japan should take the leadership role in an early realization of an e+e- linear collider. In particular, if the particle is light, experiments at low collision energy should be started at the earliest possible time.

(Now, Higgs particle has been found and it is ‘light’)

• A proposal for staging of ILC (October 2012)

– Staging • A Higgs factory with a CM energy of ~250 GeV to start

• Upgraded in stages to ~500 GeV (TDR baseline)

• Technical expandability to ~1 TeV to be secured

– Guideline for cost sharing • The host country to cover 50% of the expenses (construction) of

the overall project of the 500 GeV machine. The actual contributions left to negotiations among the governments.

68

Support by Industries: A report by the Association of Corporate Executives (経済同友会: one of the two such groups in Japan）

69

‘… The Japanese government should announce the intention to site the ILC in Japan, and propose to related countries to begin discussions toward its realization. ‘

• B: 3.5 T

• Vertex pixel detectors

– 6 (3 pairs) or 5 layers (no disks)

– Technology open

• Si-strip trackers

– 2 barrel + 7 forward disks/side (2 of the disks are pixel)

– Outer and endcap of TPC

• TPC

– GEM or MicroMEGAS

– Pad (or si-pixel) readout

• ECAL

– Si-W or Scint-W (or hybrid)

• HCAL

– Scint-tile or Digital-HCAL

ILD

All above inside solenoid

• B: 5T

• Vertex pixel detectors

– 5 barrel lyrs +

(7 disks)/side

– Technology open (3D)

• Si-strip-trackers

– 5 barrel lyrs + 4 forward disks/side

• EMCAL

– Si-W 30 lyrs, pixel ~(4mm)2

• HCAL

– Digital HCAL with RPC or GEM with (1cm)2 cell

– 40 lyrs

SiD

All above inside solenoid