Prospect of Ingot Nb Cavities for International Linear Collider...

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Prospect of Ingot Nb Cavities for International Linear Collider (ILC) Akira Yamamoto (KEK/CERN) for the Linear Collider Collaboration (LCC) To be presented at ADS-2014, Richmond, 15 Oct., 2014 1

Transcript of Prospect of Ingot Nb Cavities for International Linear Collider...

Page 1: Prospect of Ingot Nb Cavities for International Linear Collider …adsthu.org/2014.ADSThU/1.06.YAMAMOTO.pdfITRP Recommendation Progress and Prospect in SRF Cavity Gradient 14 JLab

Prospect of Ingot Nb Cavities for

International Linear Collider (ILC)

Akira Yamamoto (KEK/CERN) for the

Linear Collider Collaboration (LCC)

To be presented at ADS-2014, Richmond, 15 Oct., 2014 1

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Outline • Introduction

• Progress in SRF Accelerator R&D and Design

• Toward Realization

• Summary

2014/08/26, A. Yamamoto ILC 2

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d ν

Atom: 4E5 yrs

Proton, 1E-4 sec

Star 10E8 yrs

Nucleus 3 min.

Elementary Particles

Study of Universe/Cosmos

Hist

ory

of t

he U

nive

rse

~ 300 k Years - Limit of optical astronomical

observation Earlier Period - Elementary particle physics taking a major role, Very early universe Time range: 10-10 – 10-34 seconds being investigated by using particle accelerators

A. Yamamoto, 2014/10/15 3

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Becoming inevitable fundamental technology

Applied Superconductivy Particle Acceleratoes

SC magnet technology

Electron Acc.

SRF technology

LHC

Proton Acc.

ILC

A. Yamamoto, 2014/10/15 4

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Circular Accelerators to Linear Accelerators for Energy Frontier e+-e- Colliders

A. Yamamoto, 13/04/17 ILC Accelerator 5

SC Magnet

2T、limit

Proton

Electron

SC Cavity

ILC

For overcoming Synchroton Radiation

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ILC Technical Design Phase

A. Yamamoto, 2014/10/15 6

ILC-GDE

2005 2006 2007 2008 2012 2009 2010 2011 2013

Tech. Design:TDP1

Higgs discovered

126 GeV

Selection of SC Technology

TDP 2

Ref. Design (RDR) LCC

LHC

2004

TDR

1980’ ~ Basic Study

2013.6.12 2012.12.15

TDR completion

2014

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ILC TDR Layout

2014/08/26, A. Yamamoto

Damping Rings Polarised electron source

E+ source

Ring to Main Linac (RTML) (including bunch compressors)

e- Main Linac

e+ Main Linac

Parameters Value

C.M. Energy 500 GeV

Peak luminosity 1.8 x1034 cm-2s-1

Beam Rep. rate 5 Hz

Pulse duration 0.73 ms

Average current 5.8 mA (in pulse)

E gradient in SCRF acc. cavity

31.5 MV/m +/-20% Q0 = 1E10

ILC 7

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Higgs Boson?

Z Z boson

W W boson

γ photon

g gluon

ν τ τ-neutrino

τ tau

b bottom

t top

ν µ µ-neutrino

µ muon

s strange

c charm

νe

e-neutrino

e electron

d down

up u

Lept

ons

Qua

rks

© Brian Foster

Particles and

Forces

Discovered at LHC Precise study by ILC

A full set of Fundamental Particles

A. Yamamoto, 2014/10/15 8

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Outline • Introduction

• Progress in SRF Accelerator R&D and Design

• Toward Realization

• Summary

2014/08/26, A. Yamamoto ILC 9

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main linacbunchcompressor

dampingring

source

pre-accelerator

collimation

final focus

IP

extraction& dump

KeV

few GeV

few GeVfew GeV

250-500 GeV

ILC Accelerator Concept

SRF Technology

Nano-beam Technology

- Electron and Positron Sources (e-, e+) : - Damping Ring (DR): - Ring to ML beam transport (RTML): - Main Linac (ML):SCRF Technology - Beam Delivery System (BDS) 2014/08/26, A. Yamamoto ILC 10

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Technical Highlight in TD Phase and beyond

• SCRF Technology – Cavity: High Gradient R&D (EU, Ams, AS) :

• 35 MV/m with 50% yield by 2010 , and 90% by 2012 (TDR) • Manufacturing with cost effective design

– Cryomodule performance (EU, Ams, AS) – Beam Acceleration

• 9 mA: FLASH (DESY) • 1 ms: STF2 (KEK)- Quantum Beam

– E-XFEL construction in progress (beyond TDR) – LCLS at SLAC to be constructed

• Nano-beam handling – ILC-like beam acceleration

• Ultra-low beam emittance: Cesr-TA, ATF • Ultra-small beam size at Final Focusing, 44 nm: ATF2

2014/08/26, A. Yamamoto ILC 11

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Technical Highlight in TD Phase and beyond

• SCRF Technology – Cavity: High Gradient R&D (EU, Ams, AS) :

• 35 MV/m with 50% yield by 2010 , and 90% by 2012 (TDR) • Manufacturing with cost effective design

– Cryomodule performance (EU, Ams, AS) – Beam Acceleration

• 9 mA: FLASH (DESY) • 1 ms: STF2 (KEK)- Quantum Beam

– E-XFEL construction in progress (beyond TDR) – LCLS at SLAC to be constructed

• Nano-beam handling – ILC-like beam acceleration

• Ultra-low beam emittance: Cesr-TA, ATF • Ultra-small beam size at Final Focusing, 44 nm: ATF2

2014/08/26, A. Yamamoto ILC 12

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Björn Wiik vision

Under construction

Under construction

TDR by 2012

R&D needed

ITRP Recommendation

Progress and Prospect in SRF Cavity Gradient

2014/08/26, A. Yamamoto ILC 13

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Björn Wiik vision

Under construction

Under construction

TDR by 2012

R&D needed

ITRP Recommendation

Progress and Prospect in SRF Cavity Gradient

14 JLab and DESY leading the SRF technology and the accelerator applications

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Progress in 1.3 GHz 9-cell Cavity Production

2014/08/26, A. Yamamoto

year Capable Lab. Capable Industry 2006 1

DESY 2

ACCEL, ZANON 2011 4

DESY, JLAB, FNAL, KEK 4

RI, ZANON, AES, MHI,

2012 5 DESY, JLAB, FNAL, KEK, Cornell

5 RI, ZANON, AES, MHI, Hitachi

ILC

- One Lab (2 vendor) in 2006, and - 5 Lab (5 vendor) in 2012 may handle it

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SCRF Linac Technology

1.3 GHz Nb 9-cellCavities 16,024

Cryomodules 1,855

SC quadrupole pkg 673

10 MW MB Klystrons & modulators 436 *

Approximately 20 years of R&D worldwide Mature technology, overall design and cost

* site dependent

2014/08/26, A. Yamamoto 16 ILC

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2014/08/26, A. Yamamoto ILC

IPAC14: Courtesy: H. Weise

E-XFEL: under construction 800 Cavities under production (at RI, Zanon) , and assembled / Tested at CEA-Saclay, DESY

17

SC Linac (~ 1 km)

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SCRF Cavity Production

2014/08/26, A. Yamamoto ILC

IPAC14: Courtesy: H. Weise

2014.6: # cavities produced > 300. Usable Gradient: ~ < 30 > MV/m

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2011 disassemble S1-Global, start construction of STF accelerator(Injector + QB) 2012 Feb: QB accelerator commissioning Apr: beam acceleration Jun: beam focus for Laser-Compton Jul to Mar: experiment of Laser-Compton (QB) 2013 Apr: disassemble Laser-Compton start installation of CM-1 Sep: two set of 4-cavity train completed Oct: Cryomodule assembly in STF tunnel Dec: CM-1 completed 2014 Apr: start CM-2a assembly Jul: CM-1 and CM-2a connection will be completed Oct: Cool-down test

19

CM-1

STF Accelerator

CM-2a

CM-1

CM-2a

Will it work ? System Tests - KEK

90 % yield for 31/5 MV/m

2014/08/26, A. Yamamoto ILC

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SCRF Main Linac Parameters, Demonstrated Characteristics Parameter Unit Demonstrated

Average accelerating gradient 31.5 (±20%) MV/m DESY, FNAL, JLab, Cornell, KEK,

Cavity Q0 1010

(Cavity qualification gradient 35 (±20%) MV/m)

Beam current 5.8 mA DESY-FLASH, KEK-STF

Number of bunches per pulse 1312

Charge per bunch 3.2 nC

Bunch spacing 554 ns

Beam pulse length 730 ms DESY-FLASH, KEK-STF

RF pulse length (incl. fill time) 1.65 ms DESY-FLASH, KEK-STF, FNAL-ASTA

Efficiency (RFbeam) 0.44

Pulse repetition rate 5 Hz

Peak beam power per cavity 190* kW * at 31.5 MV/m 20 2014/08/26, A. Yamamoto ILC

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ILC Candidate Location: Kitakami Area

Oshu

Ichinoseki

Ofunato

Kesen-numa

A. Yamamoto, 2014/10/15 21

Sendai

Express- Rail

High-way

IP Region

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TDR handed to LCC Director Lyn Evans

U. Tokyo

CERN

Fermilab

ILC TDR published in a Worldwide Event: Tokyo Geneva Chicago

2014/08/26, A. Yamamoto ILC 22

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Outline • Introduction

• Accelerator R&D and Baseline Design

• Toward Realization

• Summary

2014/08/26, A. Yamamoto ILC 23

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ILC in Linear Collider Collaboration ICFA

Chair: N. Lockyer

Program Adv. Committee PAC – Chair: N. Holtkamp

FALC Chair: Y. Okada

Physics & Detectors – H. Yamamoto

CLIC – S. Stapnes

Linear Collider Board LCB – Chair: S. Komamiya

ILC – M. Harrison

Tech. Board

Linear Collider Collab. LCC Directorate

- Director: L. Evans

Deputy (Physics) – H. Murayama

Regional Directors - B. Foster (EU) - H. Weerts (AMs) - A. Yamamoto (AS)

KEK LC Project Office

KEK

ILC 2014/08/26, A. Yamamoto 24

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ILC Time Line: Progress and Prospect

A. Yamamoto, 2014/05/12

Expecting ~ (2+ 4) year Being re-studied

25

Preparation Phase

We are here, 2014 AWLC14

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SCRF Procurement/Manufacturing Model

Regional hub-laboratories responsible to regional procurements to be open for any world-wide industry participation

Regional Hub-Lab: E, & …

Regional Hub-Lab:

A

Regional Hub-Lab:

B

Regional Hub-Lab:

D

World-wide Industry responsible to

‘Build-to-Print’ manufacturing

ILC Host-Lab

Regional Hub-Lab: C: responsible to

Hosting System Test and Gradient Performance

Technical Coordination for Lab-Consortium

: Technical coordination link : Procurement link

A. Yamamoto, 2014/10/15 26

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Cavity/Cryomodule Fabrication

A. Yamamoto, 2014/10/15 27

Purchasing Material/Sub-component

Manufacturing Cavity:

Processing Surface

Assembling LHe-Tank :

Qualifying Cavity, 100 %:

Cryomodule Assembly:: CM 組立

Cavity String Assembly:

Qualifying CMs, 33 + 5 %:

Page 28: Prospect of Ingot Nb Cavities for International Linear Collider …adsthu.org/2014.ADSThU/1.06.YAMAMOTO.pdfITRP Recommendation Progress and Prospect in SRF Cavity Gradient 14 JLab

Short End group HOM1

× 8

12 EBW place

Long End group

Dumbbell x8

End cell : long side

End cell : short side

HOM2 pickup port beam pipe

beam pipe input port

center cell x8

Cavity Fabrication (TESLA Cavity)

A. Yamamoto, 2014/10/15 28

56 parts: - Nb = 46, Nb-Ti = 10, by using press, de-burring, machining 75 Electron Beam Welding (EBW) :

Page 29: Prospect of Ingot Nb Cavities for International Linear Collider …adsthu.org/2014.ADSThU/1.06.YAMAMOTO.pdfITRP Recommendation Progress and Prospect in SRF Cavity Gradient 14 JLab

SCRF Fabrication Process at KEK

29

High Pressure Code Applied

A. Yamamoto, 2014/10/15

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Process steps - fine grain Niobium

During this process foreign materials can be embedded so QA is required

A. Yamamoto, 2014/10/15 30

Courtesy: G. Myneni

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A New High Resolution, Optical Inspection System

camera

white LED half mirror

EL EL

mirror

motor & gear for mirror

camera & lens

sliding mechanism of camera

tilted sheet illumination by Electro-Luminescence

perpendicular illumination by LED & half mirror

Camera system (7µm/pix) in 50mm diameter pipe.

For visual inspection of cavity inner surface.

~600µm beads on Nb cavity

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Iwashita (Kyoto) and Hayano (KEK) et al.

DESYand FNAL also using this system in cooperation with KEK

A. Yamamoto, 2014/10/15

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Progress in SCRF Cavity Gradient in ILC Technical Design Phase

2014/08/26, A. Yamamoto

Production yield: 94 % at > 35+/-20% Average gradient: 37.1 MV/m > R&D goal of 35 MV/m reached (2012)

ILC 32

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A Direction to be Investigated for the Nb disk Mass-production

Clean surface from the beginning of Nb sheets Direct slicing from Nb Ingot (having high purity)

Proposed and patentend in the US, by G. Myneni, P. Kneisel (Jlab) and T. Carneiro (CBMM)

(Patented in Japan and in Europe, by KEK, Tokyo-Denkai, and others)

Keep clean surface w/ directly sliced Nb-sheets w/o additional rolling causing contamination and defects

On the other hand, necessary mechanical uniformity and stability for press-work

with tighter tolerance in assembly.

33 A. Yamamoto, 2014/10/15

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A Direction to be Investigated for the Nb disk Mass-production

Clean surface from the beginning of Nb sheets Direct slicing from Nb Ingot (having high purity)

Proposed and patentend in the US, by G. Myneni, P. Kneisel (Jlab) and T. Carneiro (CBMM)

(Patented in Japan and in Europe, by KEK, Tokyo-Denkai, and others)

Keep clean surface w/ directly sliced Nb-sheets w/o additional rolling causing contamination and defects

On the other hand, necessary mechanical uniformity and stability for press-work

with tighter tolerance in assembly.

34 A. Yamamoto, 2014/10/15

Page 35: Prospect of Ingot Nb Cavities for International Linear Collider …adsthu.org/2014.ADSThU/1.06.YAMAMOTO.pdfITRP Recommendation Progress and Prospect in SRF Cavity Gradient 14 JLab

A Direction to be Investigated for the Nb disk Mass-production

Clean surface from the beginning of Nb sheets Direct slicing from Nb Ingot (having high purity)

Proposed and patentend in the US, by G. Myneni, P. Kneisel (Jlab) and T. Carneiro (CBMM)

(Patented in Japan and in Europe, by KEK, Tokyo-Denkai, and others)

Keep clean surface w/ directly sliced Nb-sheets w/o additional rolling causing contamination and defects

On the other hand, necessary mechanical uniformity and stability for press-work

with tighter tolerance in assembly.

35 A. Yamamoto, 2014/10/15

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Technical Specification Example for Nb Sheet

Electrical Properties RRR: > 300

Chemical contents see table

Microstructure Re-crystalized 100 % Grain-size: ASTM 6 or finer Local grain size: ASTM 4-5

Mechanical Properties Ultimate strength: > 140 N/mm2, RT Yield strength: TBD (> xx N/mm2, RT) Elogation; > 30 % Hardness: ≤ 60

Shape/size: TBD Rect. Sheet : ~ 300 mm sq. or Circular sheet: ~280 mm dia. with a center-hole

Possibility of Blanking (in consortium: to be discussed) Thickness : 2.8 mm +/- 0.1 mm Flatness: 2 % or better Surface roughness: < 15 µm (RF side)

A. Yamamoto, 2014/10/15 36

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Technical Specification Example for Nb Sheet

Electrical Properties RRR: > 300

Chemical contents see table

Microstructure Re-crystalized 100 % Grain-size: ASTM 6 or finer to be updated to ~ 1 cm Local grain size: ASTM 4-5 to be updated

Mechanical Properties Ultimate strength: > 140 N/mm2, RT Yield strength: TBD (> 40 ~ 50 N/mm2, RT) Elogation; > 30 % Hardness: ≤ 60

Shape/size: TBD Rect. Sheet : ~ 300 mm sq. or Circular sheet: ~280 mm dia. with a center-hole

Possibility of Blanking (in consortium: to be discussed) Thickness : 2.8 mm +/- 0.1 mm Flatness: 2 % or better Surface roughness: < 15 µm (RF side)

A. Yamamoto, 2014/10/15 37

Personal comment: - Ta, fraction can be more relaxed. - However Fe fraction should be well kept very low.

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Nb Sheet directly cut out anticipated with medium grain size

RRR: ~ 200 with well controlled impurities with a level of < 10 ppm.

Grain size : ~ 1 cm (a few cm also acceptable) To be optimized for press-work,

Size: > 260 mm Thickness: ~ 2.8 mm Cleanness:

Min. surface work No rolling !!

38 A. Yamamoto, 2014/10/15

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An R&D work in progress w/CBMM/JLab-KEK Collaboration

Motivation and Progress: Comparing sliced Nb sheets with rolled Nb sheets Fabricating a single-cell cavity and Performing RF test,

Fine-grain, rolled, high RRR (300) : sample from TD Large-grain, sliced, high RRR (300) : sample from TD Large-grain, sliced, lower RRR (TBD) : sample from CBMM

We need to evaluate RRR of this sample, and KEK is planning to do

Future plan to be added: Medium-grain, sliced, lower RRR

39 A. Yamamoto, 2014/10/15

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A Slice from a Medium Grain Ingot

A. Yamamoto, 2014/10/15 40

Courtesy: CBMM

Ingot Nb with additive of Zr (~ 0.1 %)

Page 41: Prospect of Ingot Nb Cavities for International Linear Collider …adsthu.org/2014.ADSThU/1.06.YAMAMOTO.pdfITRP Recommendation Progress and Prospect in SRF Cavity Gradient 14 JLab

CBMM Ingot received and preparation in progress at KEK

41 A. Yamamoto, 2014/10/15

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R&D Plan for LG, lower RRR ingot (CBMM)

Slicing: by August, 2014

Fabrication: by December, 2014 Including Nb sample RRR measurement

Evaluation: in (early) 2015

Sincere thanks to CBMM proving the sample ingot, and to Dr. G. Myneni for this cooperation established

42 A. Yamamoto, 2014/10/15

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RRR Measurement Set-up at KEK He gas to/from Compressor

Signals

Vac. pumping

Radiation shield Sample Plat-form

Compressor Pump

G10 plate (150×100×1mm) Nb Samples to be (120×4×1mm)

T-sensor

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Process of Nb sheet from ingot

KEK, Masashi YAMANAKA 44

After wire-slicing After mechanical polishing After chemical polishing

Polishing machine Multi-wire saw

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Key Issues to be figured out Fabrication of Nb sheets

Size: 260 mm diameter, ~ 3 mm thick Quantity: ~ 18,000 x 20 = 360,000 disks (~1.2 kg/disk) Purity, Residual Resistance Ratio

RRR ~ 200 with control of impurity to be investigated (currently > 300 )

Mechanical uniformity Grain-size : to be optimized How it can be expected with industrial process?

Best solution expected Nb Ingot with medium grain-size to be optimized

45 A. Yamamoto, 2014/10/15

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Summary ILC has reached the TDR completed, and been in an

official process,by Japanese Government, for “Science justification” and “TDR validation”.

SRF cavity fabrication (industrialization) process needs to be optimized with the best cost effective approach,

Ingot Nb with a medum grain-size would be one of very logical and practical approaches, anticipated.

A. Yamamoto, 2014/10/15 46

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Acknowledgments

I would thank Dr. G Myneni for his kindest guidance and leading me to realize this opportunity.

I would thank Mr. R. Ribas and CBMM, for the kindest cooperation to provide a sample ingot and for the fruitful discussions during our visiting CBMM..

47 A. Yamamoto, 2014/10/15