ILC Accelerator Activities in North America (cooperation with - PowerPoint PPT Presentation

ILC Accelerator Activities in North America (cooperation with France) Presentation at IRFU Linear Collider Days prepared by: Marc Ross (SLAC) November 29, 2013 2013 IRFU Linear Collider Days 1

Completing the ILC Technical Design Phase  TDP Goals: » R & D to enable Project Proposal and updated Value estimate – with Cost Containment » SC RF Technology Transfer • development of a strong industrial base  Technical Design Report: » Consists of two parts: 1) R & D Report and 2) Design Description  Beam Test Facilities: » SRF Linac: Fermilab NML, DESY E-XFEL and FLASH, KEK STF » Beam Dynamics: Cornell CesrTA (2008 – 2010) » Beam Tuning: KEK ATF2  Production / Industrialization: » CEBAF Upgrade and E-XFEL January 2013 2013 IRFU Linear Collider Days 2

Completing the TDP: Outline  TDP Goals: » R & D to enable Project Proposal and updated Value estimate – with Cost Containment » SC RF Technology Transfer • development of a strong industrial base  Technical Design Report: » Consists of two parts: 1) R & D Report and 2) Design Description  Beam Test Facilities: » SRF Linac: Fermilab NML, DESY E-XFEL and FLASH, KEK STF » Beam Dynamics: Cornell CesrTA (2008 – 2010) » Beam Tuning: KEK ATF2  Production / Industrialization: » CEBAF Upgrade and E-XFEL Present 2013 IRFU Linear Collider Days 3

ILC Accelerator Activities: Outline By the end of the XFEL  SC RF Technology Transfer Production > 1000 cavities » Development of a strong industrial base will have been fabricated by industry and processed  Production / Industrialization: using the basic TESLA – » CEBAF Upgrade and E-XFEL recipe.  Beam Test Facilities: » SRF Linac: Fermilab NML, DESY E-XFEL and FLASH, KEK STF » Beam Dynamics: Cornell CesrTA (2008 – 2010) » Beam Tuning: KEK ATF2 US contribution to ‘Linear Collider Collaboration’ (LCC)  ‘P5’ prioritization activity  2013 IRFU Linear Collider Days 4

EU - XFEL  Cavity production lines fully functioning: 8 cavities / week » Two companies  Cryomodule production: • Three pre-series CM (XM-3, XM-2, XM-1) in process; typical time to construct 4 months; time to test unknown • Production series of 81 each started Sep. 02, 2013; • One CM / week nominal; one production line (CEA-Saclay) 24 cavities to be used for high – gradient development  » (See E. Elsen) 2013 IRFU Linear Collider Days 5

Jefferson Lab CEBAF 12 GeV Upgrade 'BB Lunch', M. Ross (SLAC) 6

'BB Lunch', M. Ross (SLAC) 7

Slide dated late 09.2013 All C100 cryomodules are now installed (11.2013) 'BB Lunch', M. Ross (SLAC) 8

'BB Lunch', M. Ross (SLAC) 9

SLAC Proposal:  Following BESAC (Basic Energy Sciences Advisory) report in late July 2013: » Shakeup of US accelerator construction projects: » SLAC LCLS-II project redefined » ANL APS upgrade program redefined  SLAC Proposal: » 4 GeV CW SRF Linac-based FEL » Use ILC / XFEL 1.3 GHz technology » Installed in the upstream 1/3 of the SLAC linac housing » (50 year old S-band linac to be completely removed) » First light end of FY 2019 2013 IRFU Linear Collider Days 10

SLAC Director Chi-Chang Kao, 27 September 2013: 11

Chi-Chang Kao, 27 September 2013: 12

LCLS-II and ILC Much LCLS-II construction will be done at Fermilab, using infrastructure intended for ILC 18 CM? (50%) Other CM to be made at JLab (and Cornell) Saclay CM assembly industrial experience unique US team have made ~ two ILC CM. LCLS-II effort will help understand US-domestic technical, cost, and industrialization 13

RF Parameters: 14 2013 IRFU Linear Collider Days

RF Parameters (2) 15 2013 IRFU Linear Collider Days

LCLS-II - Linac and Compressor Layout for 4 GeV L0 L1 HL L2 L3 j  0 j = - 26 ° j = - 170 ° j = - 28 ° j = 0 V 0  97 MV V 0 =235 MV V 0 =40 MV V 0 = 1448 MV V 0 = 2460 MV CM01 CM2,3 CM04 CM15 CM16 CM35 3.9 GHz LTU LH BC1 BC2 4.0 GeV GUN 98 MeV 270 MeV 1550 MeV R 56 = 0 0.75 MeV R 56 = -5 mm R 56 = -65 mm R 56 = -65 mm I pk = 1000 A I pk = 12 A I pk = 60 A I pk = 1000 A L b = 0.024 mm L b = 0.024 mm L b = 2.0 mm L b = 0.40 mm s d  0.02 % s d = 0.006 % s d = 1.4 % s d = 0.50 % 100 pC ; Machine layout 26SEP2013; Bunch length L b is FWHM j Linac V Acc. No. Cryo No. Spare Cavities (MV) Grad. Mod’s Cav’s Cav’s per (deg) (MV/m) Amplifier Includes 2-km RW wake L0 97 * 14.6 1 8 1 1 L1 235 -26 15.1 2 16 1 ? HL -40 -170 - 3 (3.9GHz) 12 0 12? L2 1448 -28 15.5 12 96 6 32? L3 2460 0 15.7 20 160 10 32? * L0 phases: (-40  , -52  , 0, 0, 0, 13  , 33  ), with cav-2 at 20% of other L0 cav’s . 2013 IRFU Linear Collider Days 16

First 800 m of SLAC linac (1964): September 6, 2013 Marc Ross, SLAC LCLS-II 17

ILC R & D initiative: Power Coupler development Mandated by PAC (12.2012) technical review Common activity with Orsay /LAL Issues: • Cost • Copper coating / flaking • Complex Assembly • Plug-compatibility 18

(1) Deep Technical Review of Input Couplers TTF3/XFEL coupler TDR coupler STF-2 coupler

ILC specification • Power requirements – We recommend to match the coupler to 30 MV/m for reduced filling time and smaller Qext range – Max coupler power at operation 450 kW (for 8.8 mA, 10Hz, Eacc=31.5 MV/m ±20%) – RF processing to at least four times max input power ~ 1.8 MW up to 500 us at test stand TW – Surface field not a problem for both designs, i.e. 40mm and 60mm are both ok – Should check flattop regulation at 25 MV/m and Qext ~ 1e7 (LFD) – TW testing on test stand up to 1.8MW has to be done for both: TTF3 and STF2 • Q-ext – Variable coupling is needed, remote operation – QL tuning range: 2-7x10 6 is needed, but we recommend 1-10 x 10 6 – 1- 10∙10 6 is achieved with TTF3 – STF2 has to be improved • Antenna alignment: – Design should be +-2mm – For TTF3 coupler the most sensitive parameter is a horizontal antenna shift/tilt. 3mm shift change QL by ~20%. Vertical tolerances are relaxed. – For STF-2 coupler this is not issue, mechanical design guarantee small shift. – TTF3 has to be improved

• Cryogenic loss: – Coupler contribution to cryogenic losses at 2K is ~5%. = not critical. – Major contribution from coupler is 70K • Conditioning time – Both designs are ok – The nominal conditioning time of < 50h is achieved/demonstrated. • Multipacting – DESY and SLAC simulations, tests and operation show no problem with TTF3 – STF2 will be simulated, tests show no problem • One vs. two windows – Many single window coupler are successful under operation – The single window would need to seal-off the cavity before the cavity-string installation into the cryomodule. – Single window coupler for ILC would need complete new development and test program of coupler (and module) – But it could be a significant cost saving • Compatibility – Cavity and attached parts (power coupler, tuner, HOM coupler, feedthroughs, He vessel, thermal connections, magnetic shield…) are tuned/balanced, it is not easy to exchange only parts of this composition – STF2 coupler design does not fit in the compatibility requirements of the TDR (40mm cavity coupler flange)

• Cost – CPI: STF2 price is 1.9 higher – Toshiba: STF2 slightly lower price – RI: about same price – Industrial study of STF2 for design optimization and cost reduction is recommended – The TTF3 coupler mass fabrication has to be investigated Recommendation: • STF2 coupler has to demonstrate stable long time (>6 month) beam operation in a CM (TTF3 coupler has a long history in FLASH) • The ILC management recommend an adapted STF2 design with 40mm cavity flange. In this case more development steps have to follow in order to realize the compatible design. The new design has to be proven with beam operation. • The concept of plug compatibility has to be further developed in view of a spare part concept. We recommend spare modules, not individual parts. • An industrial study of mass production for both designs is recommended • Industrial study of STF2 for design optimization and cost reduction is recommended.

ATF2 Program Status Glen White, SLAC January 2013 2013 IRFU Linear Collider Days 23

Detector measures measurable range signal Modulation Depth “M” determined by fringe pitch    -   N N    -   - s 2 d M cos( ) exp 2 ( k )   y y N N k 2 sin( / 2 )  - y    cos( ) d    s  2 ln depend on    y 2  M  crossing angle θ (and λ ) Focused Beam ： large M N + Small σ y N - [rad] N: no. of Compton photons Convolution between e- beam profile and fringe intensity Dilluted Beam ： small M Large σ y [rad] 13/05/29 24 2013 IRFU Linear Collider Days

174 ° 30 ° 8 ° 2 ° Crossing Expected Performance angle θ Fringe pitch 266 nm 1.03 μm 3.81 μm 15.2 μm    Measure s  d  σy* = 20 nm 〜 few μm k 2 sin( / 2 ) y with < 10% resolution Lower limit 20 nm 80 nm 350 nm 1.2 μm    cos( ) d Upper limit 110 nm 400 nm 1.4 μm 6 μm   s  2 ln    y 2  M  σ y and M for each θ mode select appropriate mode according to beam focusing 13/05/29 25 2013 IRFU Linear Collider Days