Alcator C-Mod Run 1020903 Information

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Miniproposals
Miniproposal:318
Date Filed: 8/22/2002
Title:High Performance Operation at 5 Tesla
First Author:Earl Marmar
Session Leader:Earl Marmar (shots 1-26)

Operators
Session leader(s):Earl Marmar
Physics operator(s):Jim Irby
Engineering operator(s):Ed Fitzgerald,Bill Cochran

Engineering Operator Run Comment
MP 318 High Performance Operation at 5T. Marmar/Irby/Cochran/Parkin.

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:30:397PM
Author: To Be Determined
Session leader run summary - 1020903

SL Marmar
PO Irby

Nominally we were running MP318, High performance operation at 5 Tesla. The run
was devoted to some attempts to understand the RF heating and confinement at
high input power and plasma current.

Observations:

Raising the target density seemed to make things a little worse.

1 MA was better that 1.2; the 1.0 MA shots were marginally EDA heading to
ELM-free. The 1.2 MA shots were pretty clearly ELM-free, with sub L-Mode
confinement in H-Mode.

H-factors in ohmic portions of shots were low, and systematically got lower with
increasing plasma current. This may simply be the result of EFIT getting l_i/2
slightly wrong for very low beta_p discharges, but perhaps bears further
investigation.

Best shots of the day, in terms of performance, were probably 4, 7, 17, and 19,
but they were not great. The interferometer signal was not available for shot
17, so it's not in the table of H-factors.

On shot 26, the upper triangularity was increased to 0.4 (from 0.35 on previous
shots) with no obvious benefit; q_95 only increased from 3.0 to 3.1.

shot I_p(MA) H_89(ohmic) P_RF(MW) H89(RF)

3 0.8 0.72 1.4 0.86
4 1.0 0.67 1.75 1.3
5 1.0 0.70 2.6 to 3.6 1.3 (very briefly)
7 1.0 0.67 3.9 1.27
12 1.0 0.66 3.9 1.14
19 1.0 0.65 4.4 1.24
21 1.0 0.64 4.7 0.94
23 1.2 0.57 4.6 0.90
26 1.2 0.59 4.3 0.86

Physics Operator Summaries
Entered: Jul 7 2004 04:37:16:037PM
Author: To Be Determined
MP 318 High Performance Operation at 5T

SL: Marmar
PO: Irby
EO: Cochran, Fitzgerald

ECDC was run from 6:00 to 8:00 in deuterium before the run. The run
began at 10:00 as scheduled to allow time for alternator maintenance
and warmup.

We continued to have problems with the startup. Reliability was only
50%. However, some of the fizzles probably resulted from recovery problems
following 1 to 1.2 MA disruptions. The disruptions were the result of
operator errors involved with getting a good rampdown. To get rid
of the fizzles adjustments were made to all the usual parameters
including gas, bz0, and br0. ECDC between shots, following disruptions,
also seemed to help (5 minutes, D2 at 2e-4 Torr). We also noted some
jumps in the Bz0 and Br0 following disruptions.

The rf systems supplied over 4.5 MW to the plasma today. We were not
seeing much benefit from this power however. As I'm sure Earl will
detail in his report, both ohmic and rf heated plasma performance is
poor.

We had two lost cycles because of an EF1 com bank failed to charge
indication. This problem is being debugged.


Duds 01
Fizzles 12
Plasmas 11
EF1 problems 02

Cycles 26


Entry display output on Wed Sep 4 11:40:29 2002


----------------------------------------------------------------------------
1020903001 irby PHYSICS_OPERATOR Sep 3 2002 10:12:28:200AM
. . . . . . . . . . . . . . . . . . . .
No PCS changes from Friday's run --- probably a mistake

Fizzle --- almost went > 30 kA

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3427 -13.2692 -25.6043 -22.6955
dIp/dt (kA/ms): -1.3680 -2.7374 -1.8764 -0.1759
pressure (mTorr): 0.0385 0.0403 0.0399 0.0431
Bz0 (mT): -3.6838 -1.3352 0.4601 17.6417
Br0 (mT): 0.2379 -0.1424 -0.3198 -0.2177

Bz0 is low compared to last Friday, but it may change on the next shot; so no changes.
----------------------------------------------------------------------------
1020903002 irby PHYSICS_OPERATOR Sep 3 2002 10:26:47:146AM
. . . . . . . . . . . . . . . . . . . .
Another fizzle ---

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3512 -12.2760 -27.5254 -27.5396
dIp/dt (kA/ms): -1.3685 -2.8785 -2.2607 1.4146
pressure (mTorr): 0.0344 0.0329 0.0333 0.0341
Bz0 (mT): -3.1024 -0.5092 0.5050 17.4647
Br0 (mT): 0.1988 -0.1887 -0.2317 -0.2426

Bz0 did go up.

Prepuff does look low --- increase for next shot

Got more Ip ~ 40 kA
CII level down a factor of three from first shot
----------------------------------------------------------------------------
1020903003 irby PHYSICS_OPERATOR Sep 3 2002 10:48:01:286AM
. . . . . . . . . . . . . . . . . . . .
Increased pre-puff by 2 ms to 25 ms

Plasma --- h-mode from .6 to 1.5 s

W at 72 kJ, radiated power pretty high during rf
----------------------------------------------------------------------------
1020903004 irby PHYSICS_OPERATOR Sep 3 2002 11:05:35:126AM
. . . . . . . . . . . . . . . . . . . .
Increased Ip to 1000 kA from 800 kA

Plasma --- a couple of h-modes

H/D creeping up. Will start ECDC after next shot
----------------------------------------------------------------------------
1020903005 irby PHYSICS_OPERATOR Sep 3 2002 11:19:46:256AM
. . . . . . . . . . . . . . . . . . . .
Dropped TF current from 154 to 145 kA: Field to 5.1 T from 5.4

dW 70 kJ for 2.5 MW --- not too far off the curve

----------------------------------------------------------------------------
1020903006 irby PHYSICS_OPERATOR Sep 3 2002 11:41:46:840AM
. . . . . . . . . . . . . . . . . . . .
ECDC for 5 minutes before shot --- drop H/D?

TF current from 145 to 143 to get us to 5.1 T

Pre-puff back to 23 ms ---- ecdc effect

Fizzle

Pressure was high relative to shot 5 --- .0451 vs .0417

----------------------------------------------------------------------------
1020903007 irby PHYSICS_OPERATOR Sep 3 2002 11:57:56:786AM
. . . . . . . . . . . . . . . . . . . .
RF from 0.8 to 1.3 s

Plasma, but disruption --- vertical instability

----------------------------------------------------------------------------
1020903008 irby PHYSICS_OPERATOR Sep 3 2002 12:11:09:890PM
. . . . . . . . . . . . . . . . . . . .
Moved rampdown from 1.5 to 1.3 s

strong fizzle
----------------------------------------------------------------------------
1020903009 irby PHYSICS_OPERATOR Sep 3 2002 12:28:11:870PM
. . . . . . . . . . . . . . . . . . . .
Br0 tweaked from .002 to .0015 T.

Shot 008:
Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3427 -19.1009 -33.0441 -31.1144
dIp/dt (kA/ms): -2.1017 -3.3873 -1.7491 -0.0781
pressure (mTorr): 0.0412 0.0408 0.0394 0.0385
Bz0 (mT): -2.8265 -0.5472 0.3797 14.4197
Br0 (mT): 0.1744 0.2265 0.3651 -0.2322

Fizzle --- forgot to load the Br0 tweak



Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.9888 -18.1361 -33.3770 -33.3884
dIp/dt (kA/ms): -1.9740 -3.5145 -2.2416 1.0666
Bz0 (mT): -2.0775 0.1742 1.1251 15.5779
Br0 (mT): 0.3264 0.2090 0.1928 -0.2124
----------------------------------------------------------------------------
1020903010 irby PHYSICS_OPERATOR Sep 3 2002 12:41:36:670PM
. . . . . . . . . . . . . . . . . . . .
Loaded Br0 tweak

Increased pre-puff from 23 to 24 ms

fizzle ----

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 2.0030 -17.8031 -36.3000 -33.7157
dIp/dt (kA/ms): -1.7982 -3.8668 -2.4013 1.2240
pressure (mTorr): 0.0377 0.0390 0.0385 0.0352
Bz0 (mT): -1.5421 0.2847 0.4003 14.8565
Br0 (mT): -0.2836 -0.3069 -0.1414 -0.6825
----------------------------------------------------------------------------
1020903011 irby PHYSICS_OPERATOR Sep 3 2002 12:56:59:380PM
. . . . . . . . . . . . . . . . . . . .
Increased pre-puff again to 26 ms

fizzle --- next tweak Bz0


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.6813 -19.1095 -34.3532 -32.0991
dIp/dt (kA/ms): -2.0058 -3.5805 -2.1304 1.5753
pressure (mTorr): 0.0408 0.0426 0.0408 0.0373
Bz0 (mT): -1.7336 0.1668 0.8254 15.1149
Br0 (mT): -0.2734 -0.2035 -0.2482 -0.5375
----------------------------------------------------------------------------
1020903012 irby PHYSICS_OPERATOR Sep 3 2002 1:13:04:483PM
. . . . . . . . . . . . . . . . . . . .
EF4 from -1315 to -1330 Amps

Plasma into rampdown but did disrupt ---- forgot to tweak elongation

----------------------------------------------------------------------------
1020903013 irby PHYSICS_OPERATOR Sep 3 2002 1:47:10:723PM
. . . . . . . . . . . . . . . . . . . .
Nl04 increased to 9e19 from 8e19 /m^2

moved rcur and clearin changes to 1.3 s from 1.5 s

----------------------------------------------------------------------------
1020903014 irby PHYSICS_OPERATOR Sep 3 2002 2:14:45:283PM
. . . . . . . . . . . . . . . . . . . .
Changed density feedback to Z-Meter: loaded seg 2, wire 14 --- shot 1010621001


EF1 did not charge --- waiting for igor
----------------------------------------------------------------------------
1020903015 irby PHYSICS_OPERATOR Sep 4 2002 9:00:14:166AM
. . . . . . . . . . . . . . . . . . . .
fizzle
----------------------------------------------------------------------------
1020903016 irby PHYSICS_OPERATOR Sep 4 2002 9:00:24:040AM
. . . . . . . . . . . . . . . . . . . .
fizzle
----------------------------------------------------------------------------
1020903017 irby PHYSICS_OPERATOR Sep 3 2002 2:57:19:020PM
. . . . . . . . . . . . . . . . . . . .
No changes. Try again

Plasma, but lost it at 1.48 s

Got 150 kJ

H/D at 7%

----------------------------------------------------------------------------
1020903018 irby PHYSICS_OPERATOR Sep 3 2002 3:08:10:753PM
. . . . . . . . . . . . . . . . . . . .
moved gain increase on z-meter feedback to .1 s from .2 s
ramped clearin down faster starting at 1.3
ramped rcu in faster starting at 1.3

fizzle --- looks like gas creeped up a little
----------------------------------------------------------------------------
1020903019 irby PHYSICS_OPERATOR Sep 3 2002 3:19:14:430PM
. . . . . . . . . . . . . . . . . . . .
Reduced prefill by 2 ms

Plasma --- good rampdown

140 kJ, but it takes 4.4 MW to do it.

density still low
----------------------------------------------------------------------------
1020903020 irby PHYSICS_OPERATOR Sep 3 2002 3:34:55:796PM
. . . . . . . . . . . . . . . . . . . .
increased z-meter feedback request to 0.3 from 0.25

added 1 ms to pulsed gas

dud -----
----------------------------------------------------------------------------
1020903021 irby PHYSICS_OPERATOR Sep 3 2002 3:51:05:523PM
. . . . . . . . . . . . . . . . . . . .
Turned off argon

Did 5 minutes of ECDC in D2 at 2e-4 Torr

Reduced prefill by 2 ms, now 23 ms

plasma for 1.42 s

h/d 5 to 8 % --- a little better



----------------------------------------------------------------------------
1020903022 irby PHYSICS_OPERATOR Sep 3 2002 4:06:53:800PM
. . . . . . . . . . . . . . . . . . . .
Ip to 1.2 MA from 1.0 MA

5 minutes ECDC before shot

fizzle
----------------------------------------------------------------------------
1020903023 irby PHYSICS_OPERATOR Sep 3 2002 4:27:21:236PM
. . . . . . . . . . . . . . . . . . . .
Reduced argon pressure to 1 psi from 1.8.

No PCS changes

Plasma to 1.37 s

Got 1.17 MA, but only 130 kJ with 4.5 MW
----------------------------------------------------------------------------
1020903024 irby PHYSICS_OPERATOR Sep 3 2002 4:42:45:713PM
. . . . . . . . . . . . . . . . . . . .
Changed RXU from -.02 to -.03 to increase upper triangularity

fizzle

jump in Br0 and Bz0 possibly from disruption

----------------------------------------------------------------------------
1020903025 irby PHYSICS_OPERATOR Sep 3 2002 4:54:20:683PM
. . . . . . . . . . . . . . . . . . . .
Br0 offset from 0.0015 to 0.00125

fizzle!
----------------------------------------------------------------------------
1020903026 irby PHYSICS_OPERATOR Sep 4 2002 8:57:44:803AM
. . . . . . . . . . . . . . . . . . . .
Nice Plasma, but ended in 1 MA disruption

120 kJ, 4.3 MW
----------------------------------------------------------------------------
1020903xxx irby PHYSICS_OPERATOR Sep 3 2002 7:29:01:980AM
. . . . . . . . . . . . . . . . . . . .
Did coldstart:

rtnode -- data loaded, A matrix responds
rtnode -- data loaded, M matrix responds
rtnode -- data loaded, PID matrix responds
RT_NODE Done 3-SEP-2002 07:27:02.34
----------------------------------------------------------------------------
1020903xxx irby PHYSICS_OPERATOR Sep 3 2002 8:07:58:243AM
. . . . . . . . . . . . . . . . . . . .
Engineering Setup for Tuesday, September 3,2002

MP 318 High Performance Operation at 5T

SL: Marmar
PO: Irby

ECDC from 6:00 to 8:00 in deuterium before the run.

Run Begins at 10:00 and ends at 17:00

Power systems setup as for Shot 1020830031

Gas setup:

B-Top 6 psi D2 Hybrid Enabled (PG4)
B-side lower 1 psi Ar Hybrid Enabled (PG1)
B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC)
C-Side 30 psi D2 Hybrid Enabled (PG3)
J-Bottom leave as is, Hybrid DISABLED

Enable the following gate valves

ECE, VUV

RF Setup: Transmitters 1,2,3,4 in Run On by 08:00

RUN PLAN:

Though we hope to run MP318 eventually, but we will start out
spending the time required to understand the poor performance of
the machine (low stored energy for given input power).
This process will probably involve some parameter scans at rf
levels that can be reliably produced shot-to-shot, though
I'm sure there will be many suggestions.

Session Leader Comments
Sep 3 2002 10:11:02:840AMEarl MarmarNominally running MP 318 High Performance Operation at 5T.

We'll concentrate on trying to understand the confinement and RF heating at high power.
Sep 3 2002 10:11:14:073AM1020903001Earl Marmarfizzle
Sep 3 2002 10:29:28:133AM1020903002Earl Marmarfizzle
Sep 3 2002 10:52:37:607AM1020903003Earl Marmarplasma

5.4 Tesla, .8 MA

fairly steady RF from D & J, E tripping when J is on.

70 kJ stored energy with ~2.5 MW (some on, some off axis)
Sep 3 2002 11:24:42:170AM1020903004Earl Marmarplasma

5.4 Tesla, 1 MA

First H-mode is decent; 1.7 MW, 100 kJ stored energy

H-factor looks low during initial ohmic phase (H_L ~ .7), goes up to 1.4 in first H-Mode
Sep 3 2002 11:27:13:347AM1020903005Earl Marmarplasma

5.2 Tesla, 1 MA

First H-mode is decent; 3.4 MW, 120 kJ stored energy
H_L ~ 1.4; looking somewhat ELM-free (density and Prad climbing)
Sep 3 2002 11:32:45:387AM1020903006Earl MarmarECDC for 5 minutes before shot

fizzle
Sep 3 2002 11:54:53:657AM1020903007Earl Marmarplasma

137 kJ, 3.9 MW

Radiated power rising during first H-Mode, but neutron rate is pretty flat until RF trip
Sep 3 2002 12:05:27:250PM1020903008Earl Marmarfizzle
Sep 3 2002 12:25:07:490PM1020903009Earl Marmarfizzle
Sep 3 2002 12:47:33:460PM1020903010Earl Marmarfizzle
Sep 3 2002 12:47:40:680PM1020903011Earl Marmarfizzle
Sep 3 2002 01:33:42:140PM1020903012Earl Marmarplasma

some 4 MW periods; very mediocre stored energy
Sep 3 2002 01:36:20:550PM1020903013Earl Marmarplasma

density feedback failed; gas on full the whole shot

no RF; disrupt at 1.3 s
Sep 3 2002 02:17:35:113PM1020903014Earl Marmarno power cycle
Sep 3 2002 02:17:44:287PM1020903015Earl Marmarfizzle
Sep 3 2002 02:38:17:130PM1020903016Earl Marmarno-power cycle
Sep 3 2002 03:00:35:883PM1020903017Earl Marmarplasma

150 kJ, between 2 and 4 MW; no interferometer signal
Sep 3 2002 03:00:43:743PM1020903018Earl Marmarfizzle
Sep 3 2002 03:21:54:243PM1020903019Earl Marmarplasma

~140 kJ, ~4 MW

Density was about the same as shot 17
Sep 3 2002 03:40:30:413PM1020903020Earl Marmardud
Sep 3 2002 04:07:49:143PM1020903021Earl Marmarplasma

poor stored energy; no argon
Sep 3 2002 05:29:27:880PM1020903022Earl Marmarfizzle
Sep 3 2002 04:31:24:070PM1020903023Earl Marmarplasma

1.2 MA

Short ELM-free H-Mode near start of RF (4.6 MW)
Gets to 130 kJ, then RF reduced to 3.3 MW and stored energy rolls off
Sep 3 2002 04:35:15:090PM1020903024Earl Marmarfizzle
Sep 3 2002 04:50:50:443PM1020903025Earl Marmarfizzle
Sep 3 2002 05:22:03:443PM1020903026Earl Marmarplasma

1.2 MA, higher delta_upper (0.4 vs 0.3 on previous shots)

in and out of ELM-free H-mode; RF power between 2 and 4 MW

poor confinement

(no ECE data)

Physics Operator Comments
Sep 3 2002 07:29:01:980AMJim IrbyDid coldstart:

rtnode -- data loaded, A matrix responds
rtnode -- data loaded, M matrix responds
rtnode -- data loaded, PID matrix responds
RT_NODE Done 3-SEP-2002 07:27:02.34
Sep 3 2002 08:07:58:243AMJim IrbyEngineering Setup for Tuesday, September 3,2002

MP 318 High Performance Operation at 5T

SL: Marmar
PO: Irby

ECDC from 6:00 to 8:00 in deuterium before the run.

Run Begins at 10:00 and ends at 17:00

Power systems setup as for Shot 1020830031

Gas setup:

B-Top 6 psi D2 Hybrid Enabled (PG4)
B-side lower 1 psi Ar Hybrid Enabled (PG1)
B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC)
C-Side 30 psi D2 Hybrid Enabled (PG3)
J-Bottom leave as is, Hybrid DISABLED

Enable the following gate valves

ECE, VUV

RF Setup: Transmitters 1,2,3,4 in Run On by 08:00

RUN PLAN:

Though we hope to run MP318 eventually, but we will start out
spending the time required to understand the poor performance of
the machine (low stored energy for given input power).
This process will probably involve some parameter scans at rf
levels that can be reliably produced shot-to-shot, though
I'm sure there will be many suggestions.
Sep 3 2002 10:12:28:200AM1020903001Jim IrbyNo PCS changes --- probably a mistake

Fizzle --- almost went > 30 kA

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3427 -13.2692 -25.6043 -22.6955
dIp/dt (kA/ms): -1.3680 -2.7374 -1.8764 -0.1759
pressure (mTorr): 0.0385 0.0403 0.0399 0.0431
Bz0 (mT): -3.6838 -1.3352 0.4601 17.6417
Br0 (mT): 0.2379 -0.1424 -0.3198 -0.2177

Bz0 is low compared to last Friday, but it may change on the next shot; so no changes.
Sep 3 2002 10:26:47:147AM1020903002Jim IrbyAnother fizzle ---

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3512 -12.2760 -27.5254 -27.5396
dIp/dt (kA/ms): -1.3685 -2.8785 -2.2607 1.4146
pressure (mTorr): 0.0344 0.0329 0.0333 0.0341
Bz0 (mT): -3.1024 -0.5092 0.5050 17.4647
Br0 (mT): 0.1988 -0.1887 -0.2317 -0.2426

Bz0 did go up.

Prepuff does look low --- increase for next shot

Got more Ip ~ 40 kA
CII level down a factor of three from first shot
Sep 3 2002 10:48:01:287AM1020903003Jim IrbyIncreased pre-puff by 2 ms to 25 ms

Plasma --- h-mode from .6 to 1.5 s

W at 72 kJ, radiated power pretty high during rf




Sep 3 2002 11:05:35:127AM1020903004Jim IrbyIncreased Ip to 1000 kA from 800 kA

Plasma --- a couple of h-modes

H/D creeping up. Will start ECDC after next shot
Sep 3 2002 11:19:46:257AM1020903005Jim IrbyDropped TF current from 154 to 145 kA: Field to 5.1 T from 5.4

dW 70 kJ for 2.5 MW --- not too far off the curve

Sep 3 2002 11:41:46:840AM1020903006Jim IrbyECDC for 5 minutes before shot --- drop H/D?

TF current from 145 to 143 to get us to 5.1 T

Pre-puff back to 23 ms ---- ecdc effect

Fizzle

Pressure was high relative to shot 5 --- .0451 vs .0417

Sep 3 2002 11:57:56:787AM1020903007Jim IrbyRF from 0.8 to 1.3 s

Plasma, but disruption --- vertical instability

Sep 3 2002 12:11:09:890PM1020903008Jim IrbyMoved rampdown from 1.5 to 1.3 s

strong fizzle


Sep 3 2002 12:28:11:870PM1020903009Jim IrbyBr0 tweaked from .002 to .0015 T.

Shot 008:
Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.3427 -19.1009 -33.0441 -31.1144
dIp/dt (kA/ms): -2.1017 -3.3873 -1.7491 -0.0781
pressure (mTorr): 0.0412 0.0408 0.0394 0.0385
Bz0 (mT): -2.8265 -0.5472 0.3797 14.4197
Br0 (mT): 0.1744 0.2265 0.3651 -0.2322

Fizzle --- forgot to load the Br0 tweak



Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.9888 -18.1361 -33.3770 -33.3884
dIp/dt (kA/ms): -1.9740 -3.5145 -2.2416 1.0666
Bz0 (mT): -2.0775 0.1742 1.1251 15.5779
Br0 (mT): 0.3264 0.2090 0.1928 -0.2124

Sep 3 2002 12:41:36:670PM1020903010Jim IrbyLoaded Br0 tweak

Increased pre-puff from 23 to 24 ms

fizzle ----

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 2.0030 -17.8031 -36.3000 -33.7157
dIp/dt (kA/ms): -1.7982 -3.8668 -2.4013 1.2240
pressure (mTorr): 0.0377 0.0390 0.0385 0.0352
Bz0 (mT): -1.5421 0.2847 0.4003 14.8565
Br0 (mT): -0.2836 -0.3069 -0.1414 -0.6825
Sep 3 2002 12:56:59:380PM1020903011Jim IrbyIncreased pre-puff again to 26 ms

fizzle --- next tweak Bz0


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 1.6813 -19.1095 -34.3532 -32.0991
dIp/dt (kA/ms): -2.0058 -3.5805 -2.1304 1.5753
pressure (mTorr): 0.0408 0.0426 0.0408 0.0373
Bz0 (mT): -1.7336 0.1668 0.8254 15.1149
Br0 (mT): -0.2734 -0.2035 -0.2482 -0.5375
Sep 3 2002 01:13:04:483PM1020903012Jim IrbyEF4 from -1315 to -1330 Amps

Plasma into rampdown but did disrupt ---- forgot to tweak elongation

Sep 3 2002 01:47:10:723PM1020903013Jim IrbyNl04 increased to 9e19 from 8e19 /m^2

moved rcur and clearin changes to 1.3 s from 1.5 s

Sep 3 2002 02:14:45:283PM1020903014Jim IrbyChanged density feedback to Z-Meter: loaded seg 2, wire 14 --- shot 1010621001


EF1 did not charge --- waiting for igor
Sep 4 2002 09:00:14:167AM1020903015Jim Irbyfizzle
Sep 4 2002 09:00:24:040AM1020903016Jim Irbyfizzle
Sep 3 2002 02:57:19:020PM1020903017Jim IrbyNo changes. Try again

Plasma, but lost it at 1.48 s

Got 150 kJ

H/D at 7%

Sep 3 2002 03:08:10:753PM1020903018Jim Irbymoved gain increase on z-meter feedback to .1 s from .2 s
ramped clearin down faster starting at 1.3
ramped rcu in faster starting at 1.3

fizzle --- looks like gas creeped up a little
Sep 3 2002 03:19:14:430PM1020903019Jim IrbyReduced prefill by 2 ms

Plasma --- good rampdown

140 kJ, but it takes 4.4 MW to do it.

density still low
Sep 3 2002 03:34:55:797PM1020903020Jim Irbyincreased z-meter feedback request to 0.3 from 0.25

added 1 ms to pulsed gas

dud -----
Sep 3 2002 03:51:05:523PM1020903021Jim IrbyTurned off argon

Did 5 minutes of ECDC in D2 at 2e-4 Torr

Reduced prefill by 2 ms, now 23 ms

plasma for 1.42 s

h/d 5 to 8 % --- a little better



Sep 3 2002 04:06:53:800PM1020903022Jim IrbyIp to 1.2 MA from 1.0 MA

5 minutes ECDC before shot

fizzle
Sep 3 2002 04:27:21:237PM1020903023Jim IrbyReduced argon pressure to 1 psi from 1.8.

No PCS changes

Plasma to 1.37 s

Got 1.17 MA, but only 130 kJ with 4.5 MW





Sep 3 2002 04:42:45:713PM1020903024Jim IrbyChanged RXU from -.02 to -.03 to increase upper triangularity

fizzle

jump in Br0 and Bz0 possibly from distruption

Sep 3 2002 04:54:20:683PM1020903025Jim IrbyBr0 offset from 0.0015 to 0.00125

fizzle!



Sep 4 2002 08:57:44:803AM1020903026Jim IrbyNice Plasma, but ended in 1 MA disruption

120 kJ, 4.3 MW

Engineering Operator Comments
ShotTimeTypeStatusComment
110:03:06:750AMPlasmaOk
210:16:35:740AMPlasmaOk
310:32:54:090AMPlasmaOk
410:50:02:400AMPlasmaOk
511:08:48:007AMPlasmaOk
611:30:28:320AMPlasmaOk
711:43:26:280AMPlasmaOk
812:01:50:103PMPlasmaOk
912:15:29:567PMPlasmaOk
1012:30:07:090PMPlasmaOk
1112:45:13:863PMPlasmaOk
1201:01:43:483PMPlasmaOk
1301:29:30:773PMPlasmaOk
1402:05:07:000PMPlasmaBadEF1U @ EF1L failed to charge
1502:15:34:720PMPlasmaOk
1602:28:48:240PMPlasmaBadEF1L failed to charge
1702:39:00:837PMPlasmaOk
1802:57:35:003PMPlasmaOk
1903:10:29:587PMPlasmaOk
2003:23:28:170PMPlasmaOk
2103:40:53:790PMPlasmaOk
2203:59:43:583PMPlasmaOk
2304:12:55:150PMPlasmaOk
2404:33:39:857PMPlasmaOk
2504:46:42:390PMPlasmaOk
2604:59:47:067PMPlasmaOk