Alcator C-Mod Run 1060505 Information

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Miniproposals
Miniproposal:355
Date Filed:11/12/2003
Title:ICRF Testing & Conditioning
First Author:Steve Wukitch
Session Leader:Steve Wukitch (shots 1-13)

Operators
Session leader(s):Steve Wukitch
Physics operator(s):Steve Wolfe,Ian Hutchinson
Engineering operator(s):Gary Dekow,Bill Byford

Engineering Operator Run Comment
MP355 ICRF troubleshooting; SL:Wukitch; PO:Hutch/Wolfe; EO:Dekow/Byford

Session Leader Plans
Entered: May 4 2006 04:44:59:613PM
Author: Steve Wukitch
Engineering setup for Friday 05-May-2006

MP ICRF Testing and Conditioning

Session leader: Wukitch
Physics operator: Hutchison

Overnight ECDC in D2, and bake at 60 C.

Run expected to begins at 11:00 and ends at 17:00
Begin lock-up at 10:30 (please check with SL for changes)
expect a delay to perform testing on J3 and install quarter wave
transformers on E

Power systems as on 1060421007 (1.0 MA fiducial, 5.4 T, LSN)

A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled.

Gas Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar + 2 psi Ne Hybrid DISABLED (PG1)
fill B-side upper as is, Hybrid DISABLED (PG2)
fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3)
fill NINJA with 12 psi D2 Enabled
Please have He on standby for B-main

Enable the following gate valves and shutters, assuming no vacuum problems:
ECE, VUV, Z-bolo shutters

Important Diagnostics: standard impurity spectroscopy, Mo source
monitor, McPherson, emissive probe
SL plan:
Prior to run:
measure J3 spectrum
depending on spectrum results - modify FMIT#3 operational point
vacuum test with 0.1 T field
multipactor discharge clean antenna
vacuum test
begin plasma ops

1. Standard fidicial discharge to test J performance
run J3 and J4 separately
maximum power in D
2. switch to He plasmas
maximum power in He
3. Current, gap, and Bt scan

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries
Entered: May 5 2006 05:02:51:780PM
Author: Ian Hutchinson
Not a bad PO day considering we didn't start till 12:30pm and had a break.
Quite a few disruptions but all were radiative injections and appeared attributable to RF.

Scorecard
__________
  Shot,Duration(s),Ipmax(MA),Result  Shot,Duration(s),Ipmax,Result
  |   01   1.976   1.017   Plasma  |   02   0.936   1.045   Plasma  |
  |   03   1.975   1.012   Plasma  |   04   1.971   1.009   Plasma  |
  |   05   1.973   1.016   Plasma  |   06   1.006   1.042   Plasma  |
  |   07   1.976   1.013   Plasma  |   08   1.134   1.059   Plasma  |
  |   09   1.975   1.017   Plasma  |   10   1.977   1.015   Plasma  |
  |   11   1.244   0.759   Plasma  |   12   1.978   0.744   Plasma  |
  |   13   0.925   0.740   Plasma 
Date 1060505:  13 shots.  13 plasmas.   0 fizzles.   0 duds.   0 System Error.
        (Plasma = Ip gt 50.0 kA   Dud = H_alpha lt  0.40 V)
Total plasma duration: 21.05 s (exceeding -101 kA)


Session Leader Comments
May 5 2006 12:47:27:787PM1060505001Steve Wukitch001 5.4 T, 1.0 MA, nl 0.75e20 m^-3
D: 0 MW
E: 0.5 MW [.7, 1.4] sec.
J: 2 MW [.7, 1.4] sec 200 msec each
Result: plasma
E: no kalmus
J: J3 ran mismatch
J4 gate locked
next: reset J4 and turnon kalmus

May 5 2006 12:50:14:753PM1060505001Steve Wukitch002 5.4 T, 1.0 MA, nl 0.75e20 m^-3
D: 0 MW
E: 0.5 MW [.7, 1.4] sec.
J: 2 MW [.7, 1.4] sec 200 msec each
Result: plasma - early disruption
E: mismatch
J: J3 ran 1 fault - ran better than yesterday
J4 briefly ran before disruption
next: different RF timing


May 5 2006 01:37:17:200PM1060505002Steve Wukitch002 5.4 T, 1.0 MA, nl 0.75e20 m^-3
D: 0 MW
E: 0.5 MW [.7, 1.4] sec.
J: 2 MW [.7, 1.4] sec 200 msec each
Result: plasma - early disruption
E: mismatch
J: J3 ran 1 fault - ran better than yesterday
J4 briefly ran before disruption
next: different RF timing

May 5 2006 01:41:59:690PM1060505003Steve Wukitch003 5.4 T, 1.0 MA, nl 0.9e20 m^-3
D: 0 MW
E: 0.5 MW [.65, 0.8] sec.
J: 2 MW [.8, 1.2] sec 100 msec each isolated
Result: plasma
E: mismatch
J: ran - 3 faults 2 MW!

May 5 2006 01:42:11:987PM1060505004Steve Wukitch004 5.4 T, 1.0 MA, nl 0.9e20 m^-3
D: 0 MW
E: 0.5 MW [.65, 0.8] sec.
J: 2 MW [.8, 1.2] sec
Result: plasma
E: mismatch
J: ran - max faults - match off - having problem with tuning
program reading data properly

May 5 2006 01:42:28:987PM1060505005Steve Wukitch005 5.4 T, 1.0 MA, nl 0.8e20 m^-3
D: 0 MW
E: 0.5 MW [.65, 0.8] sec.
J: 2 MW [.8, 1.2] sec
Result: plasma
E: mismatch but why?
J: ran -

May 5 2006 01:42:43:207PM1060505006Steve Wukitch006 5.4 T, 1.0 MA, nl 0.8e20 m^-3
D: 0 MW
E: 0.5 MW [.65, 0.8] sec.
J: 2 MW [.8, 1.2] sec
Result: plasma - early disruption
E: mismatch but why?
J: ran -

Physics Operator Comments
May 5 2006 11:43:55:593AMSteve Wolfe
Setting up for ICRF run
Import seg2 from 1060421007 (1MA,7e19,150kA)
In seg1, delay start of TF waveform to -1.0. 
Note: PG4=18ms, Br0=-.0003, IC_EF4=-1350
Load at  5-May-2006 11:43:27.00
Open tree /home/wolfe/pcs_scratch      -1
Open tree done



May 5 2006 12:32:51:893PM1060505001Steve Wolfe
Shot#1: plasma,
One small early xray burst, several injections.
RF practically non-existent. No H-mode.
Startup not bad. 
Next: repeat (after rf power room access)

May 5 2006 12:54:50:257PM1060505002Steve Wolfe
Shot#2: plasma,disrupts at 0.935sec, in H-mode during RF
J3 ran at 1MW, J4 just on before killer injection
E faulting out. Injection starts at .922
Early injection around 0.13 takes a small bite out of current. 
next: raise nl04 to 0.9e20

May 5 2006 01:03:32:333PM1060505003Steve Wolfe
Shot#3: nl04 to 0.9 
plasma, hmodes
Injection around 0.13 may be associated with current rise mhd
J3, J4 both running at 1MW, with overlap. E still otl. 
H=port side of J antenna lighting up on video view
Still getting some early runaway dump. 
Bz way too negative, so is Br
next: raise bz,br

May 5 2006 01:14:12:050PM1060505004Steve Wolfe
Shot#4: ic_ef4 from -1350 to -1335, br0 from -.0003 to 0. 
plasma, early hards much worse, this one bounced in startup
one h-mode, followed by continuous dithers(?)
J3+J4 short pulses, then faults out on retries. E still nothing but faults

next: raise pg4 to 20msec

May 5 2006 01:27:36:050PM1060505005Steve Wolfe
Shot#5: raise pg4 to 20msec
plasma. less runaway but still bouncing.
Three h-modes this time. J3&4 ramp to 2.6MW, 2faults.
E still faulting

next: raise ef4 again
May 5 2006 01:42:24:847PM1060505006Steve Wolfe
Shot#6:  raise ic_ef4 -1335 to -1325
Disrupted at ~1sec.
Still has a bounce, maybe worse; bz now looks too positive.
E still bad, J faults once at 2.4MW, coming back on at disruption

Next: EF4 back down to -1335, br0 to -.0002
May 5 2006 02:00:52:787PM1060505007Steve Wolfe
Shot#7: ic_ef4 -1325 to -1335, br0 from 0 to -.0002
plasma. Startup better, no bounce. No runaways
One short h-mode. RF crowbar on J. E has something wrong. 

J has a control power problem. E trans. line needs to be
partially disassembled to check what's wrong. Estimating
an hour of down time (I'd guess longer). 
May 5 2006 04:09:12:380PM1060505008Ian HutchinsonPlasma disrupts at 1.12s because of a big brick during RF faulting.
Some initial runaways.

No changes.
May 5 2006 04:25:55:977PM1060505009Ian HutchinsonPlasma to rampdown.
May 5 2006 04:33:03:773PM1060505010Ian HutchinsonPlasma to rampdown.

Load segment 2 from 1060504001.
May 5 2006 04:42:32:130PM1060505011Ian HutchinsonPlasma disrupts at 1.23s caused by radiation.
May 5 2006 04:59:42:900PM1060505012Ian HutchinsonPlasma to rampdown. Decent J-port operation at 2 MW.
May 5 2006 05:00:54:963PM1060505013Ian HutchinsonPlasma disrupts at 0.92s. Monster injection.

Engineering Operator Comments
ShotTimeTypeStatusComment
112:26:52:157PMPlasmaOk
212:44:34:223PMPlasmaOk
312:57:32:707PMPlasmaOk
401:09:55:397PMPlasmaOk
501:22:32:707PMPlasmaOk
601:35:56:103PMPlasmaOk
701:50:02:647PMPlasmaOk
803:55:01:163PMPlasmaOk
904:07:44:020PMPlasmaOk
1004:20:10:770PMPlasmaOk
1104:33:04:540PMPlasmaOk
1204:45:24:193PMPlasmaOk
1304:57:54:070PMPlasmaOk