Alcator C-Mod Run 1030618 Information

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Miniproposals
Miniproposal:339
Date Filed: 5/22/2003
Title:Mode Locking Studies at Lower Current
First Author:Ian Hutchinson
Session Leader:Ian Hutchinson (shots 1-35)

Operators
Session leader(s):Ian Hutchinson
Physics operator(s):Ron Parker
Engineering operator(s): Unknown

Engineering Operator Run Comment
Purpose: MP339, Mode locking Studies at Lower Current/Hutchinson/Parker

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:33:320PM
Author: Ian Hutchinson
Session Leader 1020618. Mode Locking at Lower Current MP 339.
_____________________________________________________________
SL Hutch. PO Parker.

This was a very successful run. About 80% of the miniproposal was
completed. We demonstrated locked mode suppression and causation
using several new coil configurations corresponding to a good range
of phases.

Locked modes were easily obtained at 0.6MA current for NL04 ~0.25e20,
but somewhat harder to diagnose than at higher current. In general we
confirm that configuration A is close to being aligned with the
intrinsic error, but there are others near it that are also
effective. We were able to push the current in the D and A
configurations sufficiently past its optimum stabilizing value to
cause a locked mode on the other side (shots 10, 34). These and other
observations should enable us to place much better quantitative limits
on the intrinsic and locking field levels. But more careful analysis
is needed than this brief summary.

The following table summarizes the immediate observations of this
day's run. The configurations are specified in the logbook and in the
miniproposal.


(These coil currents are cited using -160A as offset. Too small. Add 100A.)

shot config I_acoil set nl04 locked phase Iacmax
at lock (A) (s) (deg) (A)
1 A 0 0 .16 1.205 23 0
2 A 2300 4000 .36 0 23 2300
3 A 1160 2000 .4 0 23 1160
4 A 0 0 .4 0 23 0
5 A 0 0 .21 1.38 23 0
6 A 0 2000 .24 -2 23 1160
7 A 360 1000 .24 0 23 360
8 -D 2160 4000 .2 .66 -110 2660
9 -D 1650 3000 .23 .95 -110 1880
10 D 2770 5000 .28 1.32 70 2770
11 D 1920 3000 .22 0 70 1920
12 -E 1670 5000 .22 .79 -146 2770
13 -E 1150 2000 .22 .95 -146 1200

15 E 0 5000 .21 -2 34 2830
16 E 0 0 .21 1.30 34 0
17 -F 1700 5000 .21 .79 -129 2300
18 -F 900 2000 .19 .94 -129 1150

20 F 0 5000 .25 -2 51 2300
21 G 2340 5000 .21 .89 8 2730
22 G 0 2000 .23 0 8 1150
23 -G 0 5000 .21 -1 -172 2770
24 -G 0 2000 .20 -1 -172 1200
25 -G 0 2000 .27 -1 -172 1200
26 -H 2280 5000 .31 .88 -75 2740
27 -H 0 2000 .22 -1 -75 1220
28 H 2820 5000 .32 1.2 105 2820
29 H 1620 2500 .31 1.41 105 1620
30 H 0 1500 .27 -1 105 820

33 E 0 5000 .30 0 34 2930
34 A 2300 5000 .32 1.05 23 2300
35 -G 1200? 5000 .27 0.73? -172 2780

-1 locked time implies possible permanent lock.
-2 implies initially possibly locked, then possibly unlocking.

6 20 start locked and unlock later.
15 is disputed whether it unlocks.
23-25 27 30 permanently locked.
35 may be permanently locked.


Physics Operator Summaries
Entered: Jul 7 2004 04:37:18:397PM
Author: Ron Parker
Engineering Setup & Run Plan for Wednesday, June 18, 2003

PURPOSE: MP339, Mode Locking Studies at Lower Current

Session Leader: Hutchinson

Physop: Parker

ENGINEERING SETUP

NO ECDC. 60 C Bake Overnight

Run Starts at 9:00 AM and Ends at 5:00 PM

Power Systems as for 1030612004

Gas setup:

Fill B-Top with 6 psi of D2 hybrid enabled (PG4)
Fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
Fill B-side upper with 10 psi D2 Hybrid Disabled (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

ICRF:No ICRF required for this run.

Enable the ECE and DNB gate-valves, assuming no vacuum problems

RUN PLAN

We will begin with a low density, 600 kA shot similar to shot 1030612004.
However, pulsed gas operation during the shot will be disabled and we
will only inject the prepulse gas in order to keep the density low.The
plan is to establish locked modes and use the locked-mode coils to
determine their hopefully beneficial effect.


Run Summary

The machine ran exceptionally well for this run, although the conditions
were not very demanding: I ~ 600 kA, B ~ 4 T, n ~ 2-3e19 m-3.Locked modes
were produced with these plasma parameters and the effect of various
configurations of the locked mode coils were investigated at different
current levels.See session leader's summary.

Scorecard: 35 shots, 1 disruption due to interferometer problem and 3 duds:
1 due to pulsed gas failing to fire, 1 due to EF3 not turning on and 1 due to
EF3 breaker pulling.


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1030618001 PARKER PHYSICS_OPERATOR Jun 18 2003 9:39:37:153AM
. . . . . . . . . . . . . . . . . . . .
Shot 1 was a low density shot with flat top at 4 T, 600 kA. Hard x-rays were strong.
A coil was not energized.
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1030618002 PARKER PHYSICS_OPERATOR Jun 18 2003 9:39:08:403AM
. . . . . . . . . . . . . . . . . . . .
Shot 2 was similar, except A coil was on with setting 4000 on PCS.
Density was higher at 3.5e13. Same current and field as in shot 1.
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1030618003 PARKER PHYSICS_OPERATOR Jun 18 2003 9:47:56:526AM
. . . . . . . . . . . . . . . . . . . .
Shot 3 was similar to shot 2 except A coil PCS setting was 2000.

Density was 4e13, somewhat less overshoot on Ip as it approached 600 kA.

Hard X-rays were much reduced relative to first two shots.

Next shot: A coil current set to 0, triangularity reduced.
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1030618004 PARKER PHYSICS_OPERATOR Jun 18 2003 10:01:25:060AM
. . . . . . . . . . . . . . . . . . . .
Shot 4 ran as programmed.

Next shot: Density will be programmed for 2.5e13, RCLEAR reduced by 6mm,
RCUR by 3mm, so outer gap should not change. Trying to improve stability.
----------------------------------------------------------------------------
1030618005 PARKER PHYSICS_OPERATOR Jun 18 2003 10:12:36:066AM
. . . . . . . . . . . . . . . . . . . .
Shot 5 ran as programmed with density ~ 2e19. Lock mode appeared at t=1.38 s

Next shot: A coil on and set to 2000 on PCS.
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1030618006 PARKER PHYSICS_OPERATOR Jun 18 2003 10:22:41:333AM
. . . . . . . . . . . . . . . . . . . .
Shot 6 ran as programmed, density ~ 2.3-2.4e19.
No locked mode. Next shot: A coil at 1000 (PCS), 5 ms more Argon.

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1030618007 PARKER PHYSICS_OPERATOR Jun 18 2003 10:46:20:853AM
. . . . . . . . . . . . . . . . . . . .
Shot 7 ran as programmed. Very similar to shot 6.


Next shot: Locked mode coil configuration changed.
A coil current set at 4000. Argon pulse increased by
5 msec to 30 msec.
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1030618008 PARKER PHYSICS_OPERATOR Jun 18 2003 10:59:42:806AM
. . . . . . . . . . . . . . . . . . . .
Shot 8 ran well. Locked mode appeared during ramp up of "correction coil" current.
This was expected.

Next shot: A coil current will be ramped, starting at 0.5 s, ramping to 3000 at
1.0 s and held there until 1.5 s.
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1030618009 PARKER PHYSICS_OPERATOR Jun 18 2003 11:19:41:266AM
. . . . . . . . . . . . . . . . . . . .
Shot 9 ran well. Locked mode appeared at 0.9 s.

Next shot: A-coil current will be reversed and the height of
the ramp will be 5000 on PCS.
There was a slight delay to check an indicated fuse outage. No fuses were blown.
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1030618010 PARKER PHYSICS_OPERATOR Jun 18 2003 11:32:31:326AM
. . . . . . . . . . . . . . . . . . . .
The shots continue to run well. Locked mode occured at ~ 1.35 sec.
Next shot: Max A Coil current reduced to 3000.
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1030618011 PARKER PHYSICS_OPERATOR Jun 18 2003 11:48:15:740AM
. . . . . . . . . . . . . . . . . . . .
Shot 11 ran as programmed. New A Coil configuration for next shot.
A coil setting = 5000.
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1030618012 PARKER PHYSICS_OPERATOR Jun 18 2003 11:59:43:310AM
. . . . . . . . . . . . . . . . . . . .
Shot 12 ran well with a locked mode occuring at ~ 0.8 sec.
Next shot: A coil current = 2000, same configuration as in shot 12.
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1030618013 PARKER PHYSICS_OPERATOR Jun 18 2003 12:08:18:653PM
. . . . . . . . . . . . . . . . . . . .
Shot 13 ran without locked mode.

Nextshot: A coil current will be reversed from shot 13, amplitude = 5000.
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1030618014 PARKER PHYSICS_OPERATOR Jun 18 2003 12:22:47:796PM
. . . . . . . . . . . . . . . . . . . .
We lost density control on that shot due to laser failure before shot.
Shot disrupted at 0.95 msec. We'll repeat shot on shot 15.
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1030618015 PARKER PHYSICS_OPERATOR Jun 18 2003 12:38:54:760PM
. . . . . . . . . . . . . . . . . . . .
Shot 15 recovered and was a normal shot.
Next shot: A-coil current = 0.
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1030618016 PARKER PHYSICS_OPERATOR Jun 18 2003 12:58:43:890PM
. . . . . . . . . . . . . . . . . . . .
Shot 16 ran well. Mysterious density bump occurs from .18 - .35 sec, as in a few
previous shots. This is not due to any gas valve programming. Instead it is
due to problems with interferometer feedback signal.

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1030618017 PARKER PHYSICS_OPERATOR Jun 18 2003 1:06:29:650PM
. . . . . . . . . . . . . . . . . . . .
Shot 17 ran well, with small plasma-wall interaction during rampdown.

Next shot, A coil current = 2000.


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1030618018 PARKER PHYSICS_OPERATOR Jun 18 2003 1:15:47:446PM
. . . . . . . . . . . . . . . . . . . .
Shot 18 ran well.
Next shot: reverse current direction in A coil, I = 5000.
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1030618019 PARKER PHYSICS_OPERATOR Jun 18 2003 1:28:43:366PM
. . . . . . . . . . . . . . . . . . . .
Ooops - no EF 3, no plasma. Repeat on next shot.
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1030618020 PARKER PHYSICS_OPERATOR Jun 18 2003 1:46:09:366PM
. . . . . . . . . . . . . . . . . . . .
Shot 20 ran again, similar to preceeding shots. No locked mode.
Next shot: New configuration of locked mode coils.
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1030618021 PARKER PHYSICS_OPERATOR Jun 18 2003 2:01:38:153PM
. . . . . . . . . . . . . . . . . . . .

Shot 21 ran well with good locked mode supression.
Next shot: A coil current = 2000.
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1030618022 PARKER PHYSICS_OPERATOR Jun 18 2003 2:19:01:746PM
. . . . . . . . . . . . . . . . . . . .
Shot 22 ran well, no locked mode apparent.
Next shot: same as 22 but with reversed polarity and current = 5000.
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1030618023 PARKER PHYSICS_OPERATOR Jun 18 2003 2:28:47:136PM
. . . . . . . . . . . . . . . . . . . .
Shot 23 ran uneventfully.
Next shot: 2000 on A coil supply.
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1030618024 PARKER PHYSICS_OPERATOR Jun 18 2003 3:37:15:306PM
. . . . . . . . . . . . . . . . . . . .
Shot 24 ran as programmed. Small sawteeth -- maybe locked for the whole
shot? Next shot: nl04 = 3.2e19.
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1030618025 PARKER PHYSICS_OPERATOR Jun 18 2003 3:37:31:400PM
. . . . . . . . . . . . . . . . . . . .
Shot 25 ran well with slightly higher density. Still no or very small
sawteeth. Next shot: new configuration of A coils.
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1030618026 PARKER PHYSICS_OPERATOR Jun 18 2003 3:20:06:166PM
. . . . . . . . . . . . . . . . . . . .
Shot 26 ran, but interferometer did not track density.
Next shot: lower nl04 program to 2.5e19 and reduce current
in A Coil to 2000.
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1030618027 PARKER PHYSICS_OPERATOR Jun 18 2003 3:36:07:760PM
. . . . . . . . . . . . . . . . . . . .
Shot 27 ran well, with density =2.0e19.
Next shot: new A-coil configuration, setting = 5000.
Density will be programmed for 3.0e19.
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1030618028 PARKER PHYSICS_OPERATOR Jun 18 2003 3:45:03:576PM
. . . . . . . . . . . . . . . . . . . .
Shot 28 ran with nel4 = 3e19. Nice example of locking at ~1.2 sec.
Next shot: Same A - coil configuration reduce current to 2500.
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1030618029 PARKER PHYSICS_OPERATOR Jun 18 2003 4:12:23:473PM
. . . . . . . . . . . . . . . . . . . .
Shot 29 ran well, with loced mode occurring toward end of flat top.
Next shot: reduced A-Coil current - 1500.
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1030618030 PARKER PHYSICS_OPERATOR Jun 18 2003 4:13:25:223PM
. . . . . . . . . . . . . . . . . . . .
Shot 30 ran well, current in a-coil was 1500 on PCS.
next shot: new configuration of A-coil, current =5000.
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1030618031 PARKER PHYSICS_OPERATOR Jun 18 2003 4:26:22:326PM
. . . . . . . . . . . . . . . . . . . .
Shot 31 was a dud -- no pulsed gas. It's not clear why.
Repeat the settings for next shot.
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1030618032 PARKER PHYSICS_OPERATOR Jun 18 2003 4:36:18:646PM
. . . . . . . . . . . . . . . . . . . .
Again, no plasma. This time EF3 breaker pulled before shot.
But pulsed gas fired normally. We'll keep trying.
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1030618033 PARKER PHYSICS_OPERATOR Jun 18 2003 4:54:58:083PM
. . . . . . . . . . . . . . . . . . . .
Shot 33 ran well, strong sawtooth, no locked mode.
Next shot: Configuration A, 5000 setting for current.
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1030618034 PARKER PHYSICS_OPERATOR Jun 18 2003 5:10:17:033PM
. . . . . . . . . . . . . . . . . . . .
Shot ran, there seemed to be a locked mode, but only from about 1.15 - 1.25 sec

Next (and last) shot: -G configuration, full current.
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1030618035 PARKER PHYSICS_OPERATOR Jun 18 2003 5:24:45:870PM
. . . . . . . . . . . . . . . . . . . .
The shot ran and for most of the discharge a locked mode seemed to be present.


Session Leader Comments
Jun 18 2003 08:32:55:160AMIan HutchinsonMP 339 Mode Locking Studies at Lower Current.

Ohmic run. Trying to demonstrate the induction of a
locked mode using different phasing, and to establish
the threshold for locking more quantitatively.
Jun 18 2003 12:40:52:267PMIan HutchinsonFor logbook reference here are the tables of signals
Each coil by itself:
Coil (1,1) T/A Phase (2,1) T/A Phase
BTOP 1.79e-07 0.151 6.56e-08 -0.496
BBOT 2.47e-07 1.118 8.65e-08 1.772
DTOP 2.38e-07 1.500 8.24e-08 0.933
DBOT 2.47e-07 2.374 8.65e-08 3.028
GTOP 2.38e-07 -2.898 8.24e-08 2.818
GBOT 2.47e-07 -2.024 8.65e-08 -1.370
JTOP 2.38e-07 -1.641 8.24e-08 -2.209
JBOT 2.47e-07 -0.767 8.65e-08 -0.113

The planned configurations:
Bt Bb Dt Db Gt Gb Jt Jb (1,1) T/A Phase (2,1) T/A Phase B21 mT
A 0 0 1 -1 0 0 -1 1 4.11e-07 0.3255 2.93e-07 0.3957 0.6649
B 0 0 1 1 0 0 -1 -1 8.80e-07 1.9461 1.69e-07 2.0230 0.3839
C -1 0 0 1 1 0 0 -1 8.06e-07 2.8144 3.17e-07 2.8963 0.7209
D 0 0 1 0 0 -1 -1 0 7.12e-07 1.3700 2.32e-07 1.2144 0.6950
E 0 0 1 0 0 0 -1 1 3.70e-07 0.9614 2.21e-07 0.5875 0.6633
F 0 0 1 -1 0 -1 -1 0 6.15e-07 1.0240 2.66e-07 0.8934 0.6047
G 0 0 1 -1 -1 0 0 0 4.43e-07 0.2815 2.15e-07 0.1408 0.6456
H 0 0 1 0 1 -1 0 0 4.16e-07 1.8282 1.83e-07 1.8265 0.5492
I -1 0 0 0 1 -1 0 0 3.30e-07 2.7093 2.09e-07 2.3929 0.6267
J 1 0 1 -1 0 0 0 0 3.83e-07 0.2442 1.94e-07 0.1297 0.5830
K -1 0 1 0 1 0 0 -1 6.55e-07 2.6226 2.18e-07 2.4839 0.4960
L 1 0 0 0 -1 -1 0 0 6.00e-07 0.5361 1.22e-07 0.2265 0.3650
M 0 0 1 -1 0 0 -1 0 3.70e-07 0.9614 2.21e-07 0.5875 0.6633

Jun 18 2003 09:32:53:287AM1030618001Ian HutchinsonConfig A, Iac=0.
nl04=.16, locked at 1.2s
Jun 18 2003 09:33:39:227AM1030618002Ian HutchinsonConfig A set 4000 got 2300
nl04=.36, no lock.
Jun 18 2003 09:47:58:950AM1030618003Ian HutchinsonConfig A. Iac=1160. nl04=.4, No lock.
Jun 18 2003 09:57:08:637AM1030618004Ian HutchinsonConfig A, nl04=.4, Iac=0
No lock.
Jun 18 2003 10:14:30:713AM1030618005Ian HutchinsonConfig A, Iac=0, nl04=.21, lock at 1.38s.
Jun 18 2003 10:20:32:827AM1030618006Ian HutchinsonConfig A, Iac=1160, nl04=.24, no lock
Jun 18 2003 10:47:18:623AM1030618007Ian HutchinsonConfig A, Iac=360, nl04=.24, no lock.
Jun 18 2003 10:59:44:463AM1030618008Ian HutchinsonConfig -D, Iac=2660, nl04=.2, lock at .66s.
Jun 18 2003 11:13:15:557AM1030618009Ian HutchinsonUse ramp up on Iac to 1s.
Lock at .95s, Iac=1650. nl04=.23
Jun 18 2003 11:34:52:910AM1030618010Ian HutchinsonConfig +D. Iac to 2770A. nl04 .28, lock at 1.32
Jun 18 2003 11:47:17:597AM1030618011Ian HutchinsonConfig D, Iac=1920, nl04=.22, no lock.
Jun 18 2003 11:58:22:727AM1030618012Ian HutchinsonConfig -E. Iac=2770. nl04=.22, lock at .79s.
Jun 18 2003 12:39:32:743PM1030618013Ian HutchinsonConfig -E, Iac=1200, nl=.22, locked t .95s
Jun 18 2003 12:31:41:217PM1030618014Ian HutchinsonConfig +E, Iac 2770. But density control lost and nl04
fell drastically leading to nonthermal ECE. It might
be that there's a locked mode at .76s but hard to be sure.
Jun 18 2003 01:01:56:230PM1030618016Ian HutchinsonConfig E, Iac=0, nl04=.20, lock at 1.3s
Jun 18 2003 01:10:33:447PM1030618017Ian HutchinsonConfig -F. Iac=2300, nl04=.21, locked at .79s.
Jun 18 2003 01:23:43:320PM1030618018Ian HutchinsonConfig -F, Iac 1150. nl04=.19, lock at .94s
Jun 18 2003 02:03:29:830PM1030618019Ian HutchinsonDud no EF3
Jun 18 2003 02:18:45:197PM1030618020Ian HutchinsonConfig +F. Iac=2300A, nl04=.25, no lock.
There are signs that this shot is locked initially
and unlocks at crossover (around .8s)
Jun 18 2003 02:04:57:307PM1030618021Ian HutchinsonConfig +G. Iac=2730, nl04=.21, lock at .89s
Jun 18 2003 02:26:23:660PM1030618022Ian HutchinsonConfig +G, Iac=1150. No lock.
Jun 18 2003 02:40:08:630PM1030618023Ian HutchinsonConfig -G. Iac=2770, nl04=.21, no lock transition.
But might be locked throughout.
Jun 18 2003 02:49:15:757PM1030618024Ian HutchinsonConfig -G. Iac=1200, nl04=.2, no lock.
Again similar to previous shot. Small sawteeth
from the start. Locked throughout?
Jun 18 2003 03:04:04:733PM1030618025Ian HutchinsonConfig -G. Raised the density to try to unlock the
mode if it is locked early. No locking transition.
Jun 18 2003 03:26:38:140PM1030618026Ian HutchinsonConfig -H. nl04=.31, Iac=2740. Lock at .88s

Jun 18 2003 03:39:37:307PM1030618027Ian HutchinsonConfig -H. nl04=.22, Iac=1220, No locked transition.
Perhaps locked throughout?
Jun 18 2003 04:03:12:293PM1030618028Ian HutchinsonConfig H, Iac=2820. nl04=.32. Lock at 1.2s
Jun 18 2003 04:03:46:420PM1030618029Ian HutchinsonConfig H, Iac=1620, nl04=.31, lock at 1.41s
Jun 18 2003 04:18:30:633PM1030618030Ian HutchinsonConfig H, nl04=.27, Iac=829. No lock transition.
Possible permanent lock.
Jun 18 2003 04:27:23:017PM1030618031Ian HutchinsonDud
Jun 18 2003 04:46:06:187PM1030618032Ian HutchinsonDud. EF3 breaker pulled before shot.
Jun 18 2003 05:18:12:693PM1030618033Ian HutchinsonConfig +E. Iac=2930. nl04=.30. No lock.
Jun 18 2003 05:16:51:633PM1030618034Ian HutchinsonConfig +A. Iac=2300, nl03=.31, Locked at 1.05s
Then unlocked again at about 1.28s.
Jun 18 2003 05:27:05:590PM1030618035Ian HutchinsonConfig -G. Iac=2780. nl04=.27.
Possible locking at 0.73 bt might have already been locked.
Thereafter surely locked.

Physics Operator Comments
Jun 18 2003 09:39:37:153AM1030618001Ron ParkerShot 1 was a low density shot with flat top at 4 T, 600 kA. Hard x-rays were strong.
A coil was not energized.
Jun 18 2003 09:39:08:403AM1030618002Ron ParkerShot 2 was similar, except A coil was on with setting 4000 on PCS.
Density was higher at 3.5e13. Same current and field as in shot 1.
Jun 18 2003 09:47:56:527AM1030618003Ron ParkerShot 3 was similar to shot 2 except A coil PCS setting was 2000.

Density was 4e13, somewhat less overshoot on Ip as it approached 600 kA.

Hard X-rays were much reduced relative to first two shots.

Next shot: A coil current set to 0, triangularity reduced.
Jun 18 2003 10:01:25:060AM1030618004Ron ParkerShot 4 ran as programmed.

Next shot: Density will be programmed for 2.5e13, RCLEAR reduced by 6mm,
RCUR by 3mm, so outer gap should not change. Trying to improve stability.
Jun 18 2003 10:12:36:067AM1030618005Ron ParkerShot 5 ran as programmed with density ~ 2e19. Lock mode appeared at t=1.38 s

Next shot: A coil on and set to 2000 on PCS.
Jun 18 2003 10:22:41:333AM1030618006Ron ParkerShot 6 ran as programmed, density ~ 2.3-2.4e19.
No locked mode. Next shot: A coil at 1000 (PCS), 5 ms more Argon.

Jun 18 2003 10:46:20:853AM1030618007Ron ParkerShot 7 ran as programmed. Very similar to shot 6.


Next shot: Locked mode coil configuration changed.
A coil current set at 4000. Argon pulse increased by
5 msec to 30 msec.
Jun 18 2003 10:59:42:807AM1030618008Ron ParkerShot 8 ran well. Locked mode appeared during ramp up of "correction coil" current.
This was expected.

Next shot: A coil current will be ramped, starting at 0.5 s, ramping to 3000 at
1.0 s and held there until 1.5 s.
Jun 18 2003 11:19:41:267AM1030618009Ron ParkerShot 9 ran well. Locked mode appeared at 0.9 s.

Next shot: A-coil current will be reversed and the height of
the ramp will be 5000 on PCS.
There was a slight delay to check an indicated fuse outage. No fuses were blown.
Jun 18 2003 11:32:31:327AM1030618010Ron ParkerThe shots continue to run well. Locked mode occured at ~ 1.35 sec.
Next shot: Max A Coil current reduced to 3000.
Jun 18 2003 11:48:15:740AM1030618011Ron ParkerShot 11 ran as programmed. New A Coil configuration for next shot.
A coil setting = 5000.
Jun 18 2003 11:59:43:310AM1030618012Ron ParkerShot 12 ran well with a locked mode occuring at ~ 0.8 sec.
Next shot: A coil current = 2000, same configuration as in shot 12.
Jun 18 2003 12:08:18:653PM1030618013Ron ParkerShot 13 ran without locked mode.

Nextshot: A coil current will be reversed from shot 13, amplitude = 5000.
Jun 18 2003 12:22:47:797PM1030618014Ron ParkerWe lost density control on that shot due to laser failure before shot.
Shot disrupted at 0.95 msec. We'll repeat shot on shot 15.
Jun 18 2003 12:38:54:760PM1030618015Ron ParkerShot 15 recovered and was a normal shot.
Next shot: A-coil current = 0.
Jun 18 2003 12:58:43:890PM1030618016Ron ParkerShot 16 ran well. Mysterious density bump occurs from .18 - .35 sec, as in a few
previous shots. This is not due to any gas valve programming. Instead it is
due to problems with interferometer feedback signal.

Jun 18 2003 01:06:29:650PM1030618017Ron ParkerShot 17 ran well, with small plasma-wall interaction during rampdown.

Next shot, A coil current = 2000.


Jun 18 2003 01:15:47:447PM1030618018Ron ParkerShot 18 ran well.
Next shot: reverse current direction in A coil, I = 5000.
Jun 18 2003 01:28:43:367PM1030618019Ron ParkerOoops - no EF 3, no plasma. Repeat on next shot.
Jun 18 2003 01:46:09:367PM1030618020Ron ParkerShot 20 ran again, similar to preceeding shots. No locked mode.
Next shot: New configuration of locked mode coils.
Jun 18 2003 02:01:38:153PM1030618021Ron Parker
Shot 21 ran well with good locked mode supression.
Next shot: A coil current = 2000.
Jun 18 2003 02:19:01:747PM1030618022Ron ParkerShot 22 ran well, no locked mode apparent.
Next shot: same as 22 but with reversed polarity and current = 5000.
Jun 18 2003 02:28:47:137PM1030618023Ron ParkerShot 23 ran uneventfully.
Next shot: 2000 on A coil supply.
Jun 18 2003 03:37:15:307PM1030618024Ron ParkerShot 24 ran as programmed. Small sawteeth -- maybe locked for the whole
shot? Next shot: nl04 = 3.2e19.
Jun 18 2003 03:37:31:400PM1030618025Ron ParkerShot 25 ran well with slightly higher density. Still no or very small
sawteeth. Next shot: new configuration of A coils.
Jun 18 2003 03:20:06:167PM1030618026Ron ParkerShot 26 ran, but interferometer did not track density.
Next shot: lower nl04 program to 2.5e19 and reduce current
in A Coil to 2000.
Jun 18 2003 03:36:07:760PM1030618027Ron ParkerShot 27 ran well, with density =2.0e19.
Next shot: new A-coil configuration, setting = 5000.
Density will be programmed for 3.0e19.
Jun 18 2003 03:45:03:577PM1030618028Ron ParkerShot 28 ran with nel4 = 3e19. Nice example of locking at ~1.2 sec.
Next shot: Same A - coil configuration reduce current to 2500.
Jun 18 2003 04:12:23:473PM1030618029Ron ParkerShot 29 ran well, with loced mode occurring toward end of flat top.
Next shot: reduced A-Coil current - 1500.
Jun 18 2003 04:13:25:223PM1030618030Ron ParkerShot 30 ran well, current in a-coil was 1500 on PCS.
next shot: new configuration of A-coil, current =5000.
Jun 18 2003 04:26:22:327PM1030618031Ron ParkerShot 31 was a dud -- no pulsed gas. It's not clear why.
Repeat the settings for next shot.
Jun 18 2003 04:36:18:647PM1030618032Ron ParkerAgain, no plasma. This time EF3 breaker pulled before shot.
But pulsed gas fired normally. We'll keep trying.
Jun 18 2003 04:54:58:083PM1030618033Ron ParkerShot 33 ran well, strong sawtooth, no locked mode.
Next shot: Configuration A, 5000 setting for current.
Jun 18 2003 05:10:17:033PM1030618034Ron ParkerShot ran, there seemed to be a locked mode, but only from about 1.15 - 1.25 sec

Next (and last) shot: -G configuration, full current.
Jun 18 2003 05:24:45:870PM1030618035Ron ParkerThe shot ran and for most of the discharge a locked mode seemed to be present.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:04:30:860AMPlasmaOk
209:21:40:390AMPlasmaOk
309:35:34:437AMPlasmaOk
409:48:40:437AMPlasmaOk
510:01:32:027AMPlasmaOk
610:14:30:587AMPlasmaOk
710:27:16:913AMPlasmaOk
810:47:31:153AMPlasmaOk
911:01:23:453AMPlasmaOk
1011:19:36:047AMPlasmaOk
1111:32:46:437AMPlasmaOk
1211:48:40:913AMPlasmaOk
1312:01:43:630PMPlasmaOk
1412:15:06:160PMPlasmaOk
1512:28:18:520PMPlasmaOk
1612:41:12:843PMPlasmaOk
1712:59:47:860PMPlasmaOk
1801:12:59:673PMPlasmaOk
1901:25:50:810PMPlasmaBadEF3 breaker opened just before the shot
2001:38:23:120PMPlasmaOk
2101:55:23:570PMPlasmaOk
2202:09:02:710PMPlasmaOk
2302:22:11:897PMPlasmaOk
2402:34:59:207PMPlasmaOk
2502:47:54:347PMPlasmaOk
2603:07:22:703PMPlasmaOk
2703:24:56:140PMPlasmaOk
2803:37:23:697PMPlasmaOk
2903:50:00:690PMPlasmaOk
3004:02:36:733PMPlasmaOk
3104:16:50:383PMPlasmaOk
3204:31:52:287PMPlasmaBadEF3 opened juprior to shot
3304:47:52:830PMPlasmaOk
3405:02:51:137PMPlasmaOk
3505:15:39:867PMPlasmaOk