IHEP02 1 3 GHz 9 cell Cavity RD

IHEP-02 1. 3 GHz 9 -cell Cavity R&D Status and Plan GAO Jie, ZHAO Tongxian, ZHAI Jiyuan, LI Zhongquan, LI Dazhang, LIU Zhenchao Institute of High Energy Physics, Chinese Academy of Sciences CHEN Jinzhe, QIAO Jianqiang Beijing Hejieli Science and Technology Development Co. Ltd. YUAN Hong, YU Huai, WANG Jinxue Beijing Institute of Aviation Materials The Third IHEP-KEK 1. 3 GHz SC Technology Collaboration Meeting Dec. 7 -8, 2010, IHEP, Beijing

OUTLINE • Backgound of the IHEP 9 -cell cavity • IHEP-02 R&D goal and schedule • IHEP-02 Fabrication Procedure • HOM coupler

BACKGROUND IHEP-01 First Vertical Test Result Of IHEP 01 20 MV/m (2010. 07. 01@KEK, STF) Ø IHEP-01: Low-Loss Type 9 -cell Cavity with Bare Tubes (VT) Ø IHEP-02: Low-Loss Type 9 -cell Cavity with Full End Groups (VT&HT)

IHEP-02 R&D GOAL, SCHEDULE • IHEP-02 with full end groups for the horizontal test • Achieve the requirement of ILC Ø 25 -35 MV/m for the vertical test Ø 20 -31. 5 MV/m for the horizontal test IHEP-02 2010 -1011 2010 2011 Fabrication 2010. 06 -2011. 01 IHEP Surface treatment 2011. 02 -03 IHEP Vertical test 2011. 04 -06 Other Lab weld helium vessel 2011. 07 assemble and HT 2011. 08 -12 IHEP

OUTLINE • Backgound of the IHEP 9 -cell cavity • IHEP-02 R&D goal and schedule • IHEP-02 Fabrication Procedure • HOM coupler

Large Grain Niobium Sheets The cavity material • disks from Ningxia OTIC (Nov. , 2008) • inspection, CP, annealing • ultrasonic and eddy current scanning tests • mechanical behavior sample test at room temp. and 4 K • RRR measurement • We do that when we made the IHEP-01

Nb sheets thickness measurement 1: NOT GOOD 2: GOOD The problem：uneven thickness like the above sketch map(1) will lead to large crack, the Uniform thickness maybe good, but we think uneven thickness like the good cketch map(2) may be better.

IHEP-02 Progress 1: deep drawing 3: Annealing after first trimming 2: trimming Some half cells After trimming, Waiting for measurement Annealing @900 OC, 3 Hours Heating and cooling speed： 300 OC/H 4: After annealing, we deep drawing the half cell again.

Comparing of the twice deep drawing 37# 6# 1# 9# 15# 36# 11# 43# 17# 4# After the first After the second deep drawing 0. 26 0. 33 0. 15 0. 22 0. 16 0. 14 0. 03 0. 22 0. 10 0. 19 0. 22 0. 11 0. 10 0. 17 0. 05 0. 16 0. 10 0. 09 Standard deviation 0. 35 0. 3 Equatorial dimensions Half cell No. 0. 25 0. 2 0. 15 0. 1 0. 05 0 0 2 4 6 half cell 8 10 12

IHEP-02 Progress The half cells Frequency measurement of the half cell length, iris and equator diameter measurement

The measurement data 2. 13 0. 26 2. 62 2. 59 2. 47 0. 16 0. 35 0. 11 0. 21 2. 64 0. 09 2. 61 2. 42 2. 55 2. 60 0. 20 0. 12 Standard Cell Average deviation / mm No. / mm 6 60. 47 0. 23 2 60. 25 0. 17 8 60. 28 0. 24 15 60. 55 0. 05 34 60. 28 0. 25 11 60. 62 0. 25 20 60. 56 0. 14 18 60. 53 0. 15 36 60. 29 0. 15 42 60. 40 0. 27 43 60. 74 0. 23 13 60. 60 0. 24 4 60. 43 0. 24 35 60. 24 0. 15 19 60. 49 0. 16 9 60. 52 0. 12 17 60. 35 0. 22 1 60. 39 0. 23 7 60. 64 0. 19 33 60. 51 0. 15 37 60. 30 0. 04 Frequency of the half cell 6 2 8 15 34 11 20 18 36 42 43 13 4 35 19 9 17 1 7 33 37 Standard deviation / mm 2. 63 0. 19 2. 43 0. 21 2. 57 0. 24 2. 59 0. 06 2. 43 0. 25 2. 53 0. 19 2. 33 0. 33 2. 50 0. 10 2. 54 0. 11 2. 59 0. 21 2. 55 0. 16 Average / mm Iris diameter Iris wall thickness Cell No. 7 4 36 33 20 17 15 34 6 9 11 1 42 13 43 19 37 35 8 18 2 Freq. MHz 1275. 25 1275. 23 1273. 90 1277. 40 1274. 08 1272. 96 1275. 57 1275. 62 1275. 48 1274. 27 1274. 71 1274. 70 1273. 64 1273. 90 1274. 53 1280. 45 1274. 73 1273. 32 1275. 91 Q 　 2300. 00 2000. 00 1900. 00 2000. 00 2200. 00 2100. 00 2090. 00 2150. 00 2350. 00 2800. 00 2100. 00 3000. 00 2700. 00 2900. 00 2200. 00 2400. 00 2900. 00 2680. 00 2700. 00

IHEP-02 Progress Ø Equator roundness reshaping Ø 20 μm chemical polishing of half cells, ultrasonic cleaning, rinsing, 3 μm chemical polishing at iris area, Rinsing, Ø EBW. New Fixtures for cell equator roundness reshaping

equator roundness reshaping result Before reshaping 37# 6# 1# 9# 15# 36# 11# 17# 4# 18# 0. 22 0. 11 0. 10 0. 17 0. 05 0. 16 0. 10 0. 09 0. 04 after reshaping 0. 06 0. 03 0. 04 0. 03 0. 06 0. 05 0. 03 0. 04 Standard deviation 0. 25 0. 2 reshaping result No. 0. 15 0. 1 0. 05 0 0 2 4 6 half cell 8 10 12

IHEP-02 Progress Dumbell without stiffening ring Dumbell with stiffening ring

stiffening rings forming

stiffening rings forming

OUTLINE • Backgound of the IHEP 9 -cell cavity • IHEP-02 R&D goal and schedule • IHEP-02 Fabrication Procedure • HOM coupler

IHEP-01 Mode; Freq. --- R/Q Boundary conditions: Electric-Electric & Magnetic-Magnetic

IHEP 01 QE CALCULATION TM 010： 1. 3 GHz，Qe 2. 88 e+010 TE 111：Freq. 1. 6023 GHz，1. 6034 GHz Qe: 4. 24 e+004，7. 85 e+004 CST Model TM 110： 1. 87 GHz，Qe 1. 37 e+004 TM 011： 2. 16 GHz Qe： 2. 97 e+004 LL cavity with Tesla HOM coupler Lines per wavelength 55 Lower mesh limit 15 Mesh line ratio limit 10

HOM coupler material Nb Stick RRR 300 D 60，L 500 5 couplers housing Nb sheet RRR 300 200× 150× 8. 8 6 Inner conductors 5 Tesla HOM couplers

IHEP-02 next plan • HOM coupler fabrication will be speed up. • End groups fabrication • Cavity Welding • IHEP-02 will be finished at early 2011

Summary • The multi-cell cavity is one of the key components for 1. 3 GHz SRF technology R&D of IHEP. • We have developed effective methods, procedures, tools and facilities to fabricate and tune the 9 -cell cavity. • The IHEP-01 finished fabrication and EBW, surface treated at IHEP and tested at KEK STF in July 2010. 20 MV/m. It will be test at kek again in early 2011. • The IHEP-02 will finish in early 2011, surface treated at IHEP and test in middle 2011.

Thanks for your attention