1. MHI#16 号機の３回目の EP2  Process log  Condition of EP2 & Rinsing process  Status of working  Monitor data during EP & Rinsing process Period : 2012/1/5~ 1/16 Process : CP @flanges, EP2(20μm) under low current density, Improved 1 st Water Rinsing, Brushing @HOM & Flange using FM-20, Degreasing(FM-20, 2%) [15min], Brushing @Flange, HPR x 2 [7 hours], Assembly in C.R., Vacuum evacuation, Leak check, Baking >100 ℃ (48hours) Preparation : Washing vacuum components with ultrasonic, Cleaning in C.R. Workers : M. Sawabe, Kirk, T. Shishido (KEK), K. Nakamura, F. Tsukada, T. Kitajima (Assist Engineering Co.), T. Okada, M. Iitake (K-VAC), M. Asano, S. Imada, T. Yanagimachi (Nihon Advanced Technology) Kirk 1 STF Cavity Group Meeting @2012/1/16

2. 2 EP acid (12/26 のサンプルを使用 ) Nb ingredient : 7.8g/ℓ HF ingredient : ? g/ℓ ( 全体 ?g/ℓ の 65% が反応に使われる ) Al ingredient : <?mg/ℓ Current density : ～ 37mA/cm 2 ( 最近の傾向より ) Cavity surface temperature : <35 ℃ Control Voltage : 温度と電流密度を見ながら制御 With normal N 2 gas flow during extracting EP acid (8ℓ/min) 1 st water rinsing (1.5hours) Improved version (25ℓ/min で 20 分間上下から流し続ける ) 1 分毎に 1 秒間水抜きを繰り返す (40 分間 ) 最後の 30 分は 10min (storing)/3min (flushing) で行う Degreasing (15 min) FM-20(2%) HPR ( ～ 7 hours) 3h32m (4 turns, w/o blind flanges) 3h32m (4 turns, w/ blind flanges) Condition of EP2 & Rinsing Brushing @HOM & Flange using FM-20 Brushing @Flange using FM-20 MHI#15 の時の方針と同じ

3. Process log ① STF Cavity Group Meeting @2012/1/16 3 1/514:00MHI#16 is carried in EP area Check every flange Polishing every flange by scotch bright 1/10 9:10Check every flange [O.K.] 10:00CP @every flange 10:37Check every flange [O.K.] / Attachment of jigs for EP HPR operation starts without cavity 11:27Set cavity to EP bed with crane 11:28Meeting for tomorrow’s working procedure 11:50Installation of cathode bar to cavity [O.K.] 13:00Set data logger to cavity (totally 12ch) 13:10Leak check with N 2 gas [O.K.] Preparation for EP is completed 13:30fin.

4. STF Cavity Group Meeting @2012/1/16 1/11 9:34Cavity rotation starts / EP acid flow starts 10:02EP2 starts / Area monitor around EP area 11:10EP2 stops [1h08m] / Idling rotation (3 rpm / 20min) / Plastic case detachment 11:30Idling rotation stops 11:31EP acid is removed from cavity with N 2 gas flow(0.020MPa) 11:43First rinsing with ultra pure water starts 13:13First rinsing with ultra pure water stops [1h30m] 13:37Detachment of restriction jigs / Data logger detached 13:48Un-installation of cathode bar from cavity / washing cathode bar (No black mark) 14:00transferring cavity from EP bed to wagon 14:10Detachment of jigs for EP / Detaching every blind teflon flange (black points exist @Bottom HOM & Probe) 14:23Brushing at every flange and HOM couplers using FM-20 / Shower rinsing 14:35Checking inside cavity [O.K.] Attachment of flanges for degreasing 14:45Flowing FM-20 into cavity 14:49Degreasing with ultrasonic starts 15:05Degreasing with ultrasonic stops [15min] 15:10Removing FM-20 from cavity Detachment of flanges for degreasing 15:35Brushing at every flange using FM-20 / Shower rinsing 15:30~Vacuum parts rinsing with ultrasonic in C.R. Process log ② 4

5. STF Cavity Group Meeting @2012/1/16 1/1115:40Transferring cavity from wagon on turntable for HPR using crane 15:48Checking tolerance between position of nozzle and center of beam pipe 15:501 st HPR for inside cavity starts 19:241 st HPR for inside cavity stops [3h32m] (4 turns) 19:28Attaching every blank flange in C.R. 20:00fin. 1/12 9:08HPR outside cavity with blind flanges starts [20mins] 9:402 nd HPR for inside cavity with blind flanges starts 13:122 nd HPR for inside cavity with blind flanges stops [3h32m] (4 turns) 13:15Cavity enters into C.R. 13:40Assembly in C.R. (Class 10) starts 14:40Assembly in C.R. (Class 10) finishes / Moving out from Class10 to Class1000 14:45Vacuum evacuation starts with heat gun warming 14:50Turbo pump ON @~200Pa 14:55Turbo pump status 100% 15:07Metal gauge ON @1.0x10 -1 Pa 15:30Leak check thoroughly @~1.0x10 -3 Pa (Leak from ICF) [O.K.] 15:45Baking @100 ℃ starts (Max Vacuum Level just after baking start : ~1.55 x 10 -3 Pa) 17:35Cavity vacuum : 4.86 x 10 -4 Pa @92 ℃ /105 ℃ /105 ℃ /115 ℃ /95 ℃ /79 ℃ /79 ℃ /19 ℃ (Cell#3/Cell#7/Top/Input/Cell#5/Probe/Bottom/Room) Process log ③ 5

6. Process log ④ STF Cavity Group Meeting @2012/1/16 6 1/13 8:45Cavity vacuum : 4.29 x 10 -5 Pa @100 ℃ /105 ℃ /131 ℃ /136 ℃ /100 ℃ /89 ℃ /90 ℃ /18 ℃ (Cell#3/Cell#7/Top/Input/Cell#5/Probe/Bottom/Room) 17:50Cavity vacuum : 3.40 x 10 -5 Pa @100 ℃ /105 ℃ /122 ℃ /130 ℃ /100 ℃ /91 ℃ /92 ℃ /19 ℃ (Cell#3/Cell#7/Top/Input/Cell#5/Probe/Bottom/Room) 1/1422:20Cavity vacuum : 2.60 x 10 -5 Pa @100 ℃ /105 ℃ /123 ℃ /131 ℃ /101 ℃ /90 ℃ /91 ℃ /19 ℃ (Cell#3/Cell#7/Top/Input/Cell#5/Probe/Bottom/Room) 22:25Baking Off Ion Pump ON 22:55Cavity vacuum : 2.42 x 10 -6 Pa @78 ℃ /81 ℃ (Cell#3/Cell#7) 1/16 8:55Cavity vacuum : 1.02 x 10 -7 Pa @21 ℃ (4.2 x 10 -8 Pa @I.P.) 9:15MHI#16 moves to V.T. stand

7. STF Cavity Group Meeting @2012/1/16 Status of 3 rd EP2 for MHI#16 ① 7 current voltage T cavity T reservoir T room T cavity average current density 平均電流密度が 37mA/cm 2 程度になる ように電圧を調整する。 (low current density EP)

8. 8 STF Cavity Group Meeting @2012/1/16 Status of 3 rd EP2 for MHI#16 ② 左図は平均電流密度と電圧の相関 右図は定常状態での分布 target

9. 最近の定常状態の比較 9 ※ MHI#12, 13, 16 号機の２回目の EP2 は 5μm しか行っていない。 Cavity Mean temp. [ ℃ ]R.M.S. temp. [ ℃ ] Mean i [mA/cm 2 ]R.M.S. i [mA/cm 2 ] MHI-A 1 st 26.10.836.51.5 MHI#12 1 st 25.60.934.51.4 MHI#13 1 st 26.90.937.41.5 MHI#12 2 nd 26.20.536.31.4 MHI#13 2 nd 26.60.737.61.6 MHI#14 1 st 26.90.537.31.6 MHI#15 1 st 27.90.936.21.5 MHI#14 2 nd 29.00.838.01.2 MHI#15 2 nd 28.10.737.30.9 MHI#16 1 st 27.41.037.41.0 MHI#16 2 nd 29.20.236.00.7 MHI#17 1 st 31.20.536.90.9 MHI#14 3 rd 31.10.536.80.7 MHI#15 3 rd 26.30.736.21.7 MHI#16 3 rd 28.90.936.61.5

10. 空洞内と外部温度との比較 STF Cavity Group Meeting @2012/1/16 10 Cavity 空洞内 上流 BP Cell#1Cell#2Cell#3Cell#4Cell#5Cell#6Cell#7Cell#8Cell#9 下流 BP 環境 MHI-A 1 st 26.1 MHI#12 1 st 25.6 MHI#13 1 st 26.9 MHI#12 2 nd 26.2 MHI#13 2 nd 26.6 MHI#14 1 st 26.935.727.134.327.832.425.525.024.823.627.132.39.6 MHI#15 1 st 27.935.428.833.431.332.829.029.226.627.228.730.010.9 MHI#14 2 nd 29.036.129.934.931.631.928.630.126.829.129.735.810.6 MHI#15 2 nd 28.133.729.128.528.033.030.030.828.830.730.238.29.5 MHI#16 1 st 27.434.326.427.327.431.829.227.728.229.424.635.310.8 MHI#16 2 nd 29.234.029.031.429.130.628.125.431.129.728.728.911.3 MHI#17 1 st 31.231.030.630.331.530.928.630.829.330.532.232.812.2 MHI#14 3 rd 31.135.530.434.730.431.1 28.931.429.632.136.914.0 MHI#15 3 rd 26.338.429.130.629.428.924.326.629.727.922.325.810.9 MHI#16 3 rd 28.940.031.234.233.535.327.431.631.532.131.828.510.8

11. Status of 3 rd EP2 for MHI#16 ③ STF Cavity Group Meeting @2012/1/16 11 #1#2#3#4#5 #6#7#8#9#10 EP2 の間の空洞表面温度の状況。 #11 #12 Steady state: 40.0 31.2 34.2 33.5 35.3 27.4 31.6 31.5 32.1 31.8 28.5 10.8 28.9 ℃

12. STF Cavity Group Meeting @2012/1/16 Status of 3 rd EP2 for MHI#16 ④ 12 #1#2#3#4#5 #6#7#8#9#10 EP2 の間の空洞表面温度の状況（前ページの最後の拡大図）。 #11 #12

13. STF Cavity Group Meeting @2012/1/16 13 #1#2#3#4#5 #6#7#8#9#10#11 #12 Status of UWR for MHI#16 ① Steady state: 14.3 12.9 13.6 12.2 12.7 12.6 12.2 13.6 12.5 12.1 14.0 17.1

14. STF Cavity Group Meeting @2012/1/16 14 一次洗浄中の空洞温度の状況（前ページの拡大図） #1#2#3#4#5 #6#7#8#9#10#11 #12 Status of UWR for MHI#16 ②

15. Status of UWR for MHI#16 ③ STF Cavity Group Meeting @2012/1/16 15

16. STF Cavity Group Meeting @2012/1/16 Status of HPR for MHI#16 16 ノズルは 1st HPR では４往復、 2nd HPR でも４往復させた。 Particle counter は修理中のためデータ無し。