Alcator C-Mod Run 1020927 Information

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Miniproposals
Miniproposal:301
Date Filed: 6/21/2002
Title:ITB Foot Location Movement via I
First Author:John Rice
Session Leader:John Rice (shots 1-32)

Operators
Session leader(s):John Rice
Physics operator(s):Jim Irby
Engineering operator(s):Gary Dekow,Bill Parkin,Ed Fitzgerald,Bill Cochran

Engineering Operator Run Comment
MP#301 ITB foot location movement via Ip scan;SL:Rice; PO:Irby; EO:Dekow

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:30:727PM
Author: To Be Determined
Session Leader Run Summary for 1020927 MP301* ITB Foot, Ip Scan

This run got off to a slow start with computer problems and 6 test shots.
There were a few decent ITBs but this run was plaqued with RF trips. On
shot 19 the current was lowered to 0.6 MA. There were the slightest hints
of ITBs on shots 22 and 29, interestingly at 4.7 T, with an apparent inward
movement of the ITB foot location, wetting our appetites.

Physics Operator Summaries
Entered: Jul 7 2004 04:37:16:317PM
Author: To Be Determined
Physop Summary for Friday, Sept 27, MP301 --- ITB Foot Location via Ip Scan

EO: Cochran, Dekow, Fitzgerald, Parkin
PO: Irby
SL: Rice

Summary
-------

The machine ran extremely well today with only one fizzle caused by a
slow upward drift in Bz0 unnoticed by the operator. Some adjustments
in the prefill were required, but only rarely.

We began the day with 6 cycle tests to debug a data system problem.
The first plasma was produced on shot 007, but without rf. On shot
008 and 009 a good eda plasma at 4.5 T and 800 kA was produced with 2
MW of rf. Some faulting in e-port did not seem to greatly affect the
plasma. Dropping the TF field to 4.4 T resulted in more elm-free like
operation with h-mode bursts, even though the rf continued to run
without faults. Some tweaks to the lower triangularity did not
improve the elm-ness as had seemed to be the case in earlier runs. On
shot 011 we had another bizarre case of 2 MW of clean rf power
producing no h-modes, very little radiation, and increased H/D. John
Rice indicated that the moly went up relative to the argon on this
shot. We obtained an h-mode again on the next shot at 4.5 T.

Later in the day, at currents of 600 kA, we had serious crossover
problem resulting in large variations in the inner and outer gaps.
Light from the inner wall seen on the wide angle video confirmed the
effect. Adjustments in the Ip gain did not cure the problem as it had
in the past. Since the rf turn-on was just before crossover, one might
have assumed the rf coupling was affected. However, delaying the rf
turn-on past the crossover time did not improve the faulting problems.
Much of the day was spent trying to get enough rf power into these low
current plasmas to produce an ITB. Some hints of the scaling of the
ITB foot location with Ip were found, but this MP will certainly need
more work.

We continue to have problems getting both d- and e-port to run
together. Shot 009 was possibly the best shot of the day in terms of
rf power, with only one fault late in the shot. On shot 017 we
reduced the request from e-port to 0.5 MW, asked for 1.5 MW from
e-port, and were able to couple 2 MW of power with some faulting in
e-port. On shot 019 we went to 600 kA, at which point operation
became even more difficult.


Score
-----

Duds 00
Fizzles 01
Plasmas 25
Test 06

---------------------------------------------------------------------------
---------------------------------------------------------------------------
1020927007 irby PHYSICS_OPERATOR Sep 27 2002 10:42:45:370AM
. . . . . . . . . . . . . . . . . . . .
Loaded shot 1020925007 into segment 2 as requested by SL

Very nice plasma --- but forgot to tell rf to run

Startup looks good
----------------------------------------------------------------------------
1020927008 irby PHYSICS_OPERATOR Sep 27 2002 10:57:35:803AM
. . . . . . . . . . . . . . . . . . . .
No PCS changes --- just added some rf

Very nice plasma --- long clean h-mode

2 MW of rf --- several trips on E

H/(H+D) upto 6% at end of h-mode


Startup good:

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -3.0537 -16.0953 -27.8191 -106.0402
dIp/dt (kA/ms): -1.3275 -2.4757 -2.8595 -6.4530
pressure (mTorr): 0.0555 0.0628 0.0607 0.0507
Bz0 (mT): -3.0484 -0.5412 1.7461 22.9528
Br0 (mT): 0.2228 -0.2866 -0.5416 0.0498

pressure up slightly

----------------------------------------------------------------------------
1020927009 irby PHYSICS_OPERATOR Sep 27 2002 11:16:32:840AM
. . . . . . . . . . . . . . . . . . . .
Prepuff from 29 to 27 ms

Reduced RXL by 2 cm ---- Increase triangularity in an attempt to make plasma less elmfree.

Plasma into rampdown

Not much change in lower triag
----------------------------------------------------------------------------
1020927010 irby PHYSICS_OPERATOR Sep 27 2002 11:37:12:473AM
. . . . . . . . . . . . . . . . . . . .
Dropped Tf from 4.53 to 4.4 T

RXL from .0130 to .005 --- too small a change was made on shot 009

Got lower field

Got increased lower triangularity --- but it's more elmfree?

rf was a solid 2 MW

----------------------------------------------------------------------------
1020927011 irby PHYSICS_OPERATOR Sep 27 2002 11:56:53:870AM
. . . . . . . . . . . . . . . . . . . .
RXL back to 0.015

Keeping TF at 4.4

Plasma into rampdown but No h-mode

good rf --- 3 e-port trips


John Rice reports lots of moly compared to the argon level on this
shot --- cause or effect?
----------------------------------------------------------------------------
1020927012 irby PHYSICS_OPERATOR Sep 27 2002 12:08:46:230PM
. . . . . . . . . . . . . . . . . . . .
Reloaded 1020927007 into seg 2 --- back to 4.5 T

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

fizzle

Bz0 drifted up

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -2.0833 -16.4355 -28.1594 -27.2069
dIp/dt (kA/ms): -1.4554 -2.5724 -1.3098 0.0813
pressure (mTorr): 0.0568 0.0543 0.0536 0.0536
Bz0 (mT): -2.0630 0.0569 1.8231 16.9981
Br0 (mT): 0.1049 -0.2090 -0.6122 -0.3415
----------------------------------------------------------------------------
1020927013 irby PHYSICS_OPERATOR Sep 27 2002 12:32:25:713PM
. . . . . . . . . . . . . . . . . . . .
EF4 from -1315 to -1330 Amps

Prepuff back to 29 ms

Plasma --- good h-mode again

John reports rotation drop
----------------------------------------------------------------------------
1020927014 irby PHYSICS_OPERATOR Sep 27 2002 12:39:06:163PM
. . . . . . . . . . . . . . . . . . . .
Repeat

h-mode, but with brief dropout during rf trip
----------------------------------------------------------------------------
1020927015 irby PHYSICS_OPERATOR Sep 27 2002 1:12:30:586PM
. . . . . . . . . . . . . . . . . . . .
EF4 to -1325 from -1330 Amps --- chase Bz0

TF to 4.7 T --- 128.653 kA

5 minutes of ecdc at 2e-4 Torr D2
Prefill from 29 to 27 ms

Plasma but several trips on E-port
----------------------------------------------------------------------------
1020927016 irby PHYSICS_OPERATOR Sep 27 2002 1:25:55:770PM
. . . . . . . . . . . . . . . . . . . .
Repeat of shot 15

Plasma --- E-port trips
----------------------------------------------------------------------------
1020927017 irby PHYSICS_OPERATOR Sep 27 2002 1:36:59:260PM
. . . . . . . . . . . . . . . . . . . .
increased d-port power and reduced e-port to try and keep more constant rf

good plasma
----------------------------------------------------------------------------
1020927018 irby PHYSICS_OPERATOR Sep 27 2002 1:46:57:840PM
. . . . . . . . . . . . . . . . . . . .
TF to 5.4T

Nice clean h-mode

Looks like .5 MW is the best we can do out of e-port
----------------------------------------------------------------------------
1020927019 irby PHYSICS_OPERATOR Sep 27 2002 2:16:22:990PM
. . . . . . . . . . . . . . . . . . . .
Ip to 600 kA; staying gat 5.4 T

plasma --- trips in d and e
----------------------------------------------------------------------------
1020927020 irby PHYSICS_OPERATOR Sep 27 2002 2:17:27:196PM
. . . . . . . . . . . . . . . . . . . .
plasam --- trips in d and e

h/(h+d) 7-8%

----------------------------------------------------------------------------
1020927021 irby PHYSICS_OPERATOR Sep 27 2002 2:23:52:240PM
. . . . . . . . . . . . . . . . . . . .
Try with just d-port

plasma
----------------------------------------------------------------------------
1020927022 irby PHYSICS_OPERATOR Sep 27 2002 2:35:08:056PM
. . . . . . . . . . . . . . . . . . . .
TF to 4.7 T, 129kA

Prefill back to 29 ms

Plasma but pretty ratty --- bad things at crossover
----------------------------------------------------------------------------
1020927023 irby PHYSICS_OPERATOR Sep 27 2002 2:58:42:963PM
. . . . . . . . . . . . . . . . . . . .
Dropped Ip gain to zero around crossover time, then increased it back to normal.

Plasma into rampdown, but still have crossover problem
----------------------------------------------------------------------------
1020927024 irby PHYSICS_OPERATOR Sep 27 2002 3:15:31:416PM
. . . . . . . . . . . . . . . . . . . .
TF to 4.5 T

Added 10 more ms of argon

Delayed gain increase in Ip another 20 ms

Ip may have looked a little better --- still lost inner gap

Heavy faulting on d-port too
----------------------------------------------------------------------------
1020927025 irby PHYSICS_OPERATOR Sep 27 2002 3:31:11:790PM
. . . . . . . . . . . . . . . . . . . .
Repeat with some rf I hope

plasma but with very little rf

move rf timing next shot to avoid crossover
----------------------------------------------------------------------------
1020927026 irby PHYSICS_OPERATOR Sep 27 2002 3:44:31:410PM
. . . . . . . . . . . . . . . . . . .
rf on at .800 ms

Delay in rf did not reduce the faulting on d-port
e-port ran cleanly at 0.5 MW
----------------------------------------------------------------------------
1020927027 irby PHYSICS_OPERATOR Sep 27 2002 3:55:13:523PM
. . . . . . . . . . . . . . . . . . . .
Ip request to 650 kA
Ip gain back to 7 to 9.

No change in crossover

Only 1.4 MW of rf
----------------------------------------------------------------------------
1020927028 irby PHYSICS_OPERATOR Sep 27 2002 4:08:11:986PM
. . . . . . . . . . . . . . . . . . . .
TF to 4.7 T

No h-modes

rf power low --- will raise for next shot
----------------------------------------------------------------------------
1020927029 irby PHYSICS_OPERATOR Sep 27 2002 4:28:21:633PM
. . . . . . . . . . . . . . . . . . . .
request more rf

better --- some h-mode activity

rotation slows --- ITB forming
----------------------------------------------------------------------------
1020927030 irby PHYSICS_OPERATOR Sep 27 2002 6:33:31:516PM
. . . . . . . . . . . . . . . . . . . .
attempt more rf

plasma ---- still only a little more than 1 MW rf --- multiple h-modes
----------------------------------------------------------------------------
1020927031 irby PHYSICS_OPERATOR Sep 27 2002 4:50:14:896PM
. . . . . . . . . . . . . . . . . . . .
repeat with more rf

plasma --- a little more rf early ---- multi h's
----------------------------------------------------------------------------
1020927032 irby PHYSICS_OPERATOR Sep 27 2002 6:32:00:590PM
. . . . . . . . . . . . . . . . . . . .
attempt to get more rf

plasma --- multiple h-modes --- no usuable ITB
---------------------------------------------------------------------------
Engineering setup for Friday, September 27th, Run 1020927

MP#301 ITB foot location movement via Ip scan
Session leader: Rice
Physics Operator: Irby

ECDC overnight in D2 stopping by 07:00.
Overnight bake at 60C

Set up for possible ECDC in D2 between shots.

Engineering setup as on 1020925007

Power systems the same as shot 1020822010 Gas setup:
fill B-Top with 6 psi 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) (for ECDC)
fill C-side with 30 psi D2 Hybrid enabled (PG3)
leave J-Bottom as is Hybrid DISABLED (PG5)

Enable the following gate valves:
ECE, VUV, DNB

-------------------------------------------------------------------------------
RF Setup: FMIT#1 and 2 transmitters in Run On by 08:00
-------------------------------------------------------------------------------




























Session Leader Comments
Sep 27 2002 10:40:54:820AM1020927001John Ricetest
Sep 27 2002 10:41:01:130AM1020927002John Ricetest
Sep 27 2002 10:41:07:977AM1020927003John Ricetest
Sep 27 2002 10:41:13:400AM1020927004John Ricetest
Sep 27 2002 10:41:18:960AM1020927005John Ricetest
Sep 27 2002 10:41:24:227AM1020927006John Ricetest
Sep 27 2002 10:41:46:460AM1020927007John Ricewould have been trophy ITB were it not for no RF
Sep 27 2002 10:56:12:490AM1020927008John Ricemoderate ITB, but multiple E port trips
Sep 27 2002 11:18:16:407AM1020927009John Riceweak ITB, good RF
Sep 27 2002 11:34:33:940AM1020927010John Riceno ITB, multiple H-L transitions, good RF
Sep 27 2002 11:50:33:970AM1020927011John Rice4.4 T, no H-mode, no ITB
Sep 27 2002 12:03:35:120PM1020927012John Ricephizzle
Sep 27 2002 12:33:29:107PM1020927013John Ricedecent ITB
Sep 27 2002 12:43:34:343PM1020927014John Ricemarginal ITB
Sep 27 2002 01:23:16:483PM1020927015John Rice4.7 T, RF trip, no ITB
Sep 27 2002 01:23:22:797PM1020927016John Rice4.7 T, RF trip, no ITB
Sep 27 2002 02:18:12:243PM1020927017John Rice4.7 T, RF trip, no ITB
Sep 27 2002 02:18:26:777PM1020927018John Rice5.4 T, RF trips, no ITB
Sep 27 2002 02:18:43:340PM1020927019John Rice5.4 T, RF trips, no ITB, 600 kA
Sep 27 2002 02:18:52:293PM1020927020John Rice5.4 T, RF trips, no ITB, 600 kA
Sep 27 2002 02:19:08:980PM1020927021John Rice5.4 T, D port only
Sep 27 2002 02:54:10:297PM1020927022John Rice4.7 T, indications of ITB
Sep 27 2002 03:03:00:457PM1020927023John Rice4.7 T, not the greatest shot ever
Sep 27 2002 03:09:20:763PM1020927024John Rice4.5 T, no H-mode, no ITB
Sep 27 2002 03:32:46:810PM1020927025John Rice4.5 T, no H-mode, no ITB
Sep 27 2002 03:41:17:750PM1020927026John Rice4.5 T, no H-mode, no ITB
Sep 27 2002 04:01:29:850PM1020927027John Rice4.5 T, no H-mode, no ITB
Sep 27 2002 04:30:29:640PM1020927028John Rice4.5 T, no H-mode, no ITB

Sep 27 2002 04:31:02:780PM1020927029John Rice4.7 T, H-mode, perhaps an ITB

Sep 27 2002 04:40:05:563PM1020927030John Rice4.7 T, no H-mode, no ITB

Sep 27 2002 04:57:58:910PM1020927031John Rice4.7 T, no ITB

Physics Operator Comments
Sep 27 2002 10:42:45:370AM1020927007Jim IrbyLoaded shot 1020925007 into segment 2 as requested by SL

Very nice plasma --- but forgot to tell rf to run

Startup looks good
Sep 27 2002 10:57:35:803AM1020927008Jim IrbyNo PCS changes --- just added some rf

Very nice plasma --- long clean h-mode

2 MW of rf --- several trips on E

H/(H+D) upto 6% at end of h-mode


Startup good:

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -3.0537 -16.0953 -27.8191 -106.0402
dIp/dt (kA/ms): -1.3275 -2.4757 -2.8595 -6.4530
pressure (mTorr): 0.0555 0.0628 0.0607 0.0507
Bz0 (mT): -3.0484 -0.5412 1.7461 22.9528
Br0 (mT): 0.2228 -0.2866 -0.5416 0.0498

pressure up slightly

Sep 27 2002 11:16:32:840AM1020927009Jim IrbyPrepuff from 29 to 27 ms

Reduced RXL by 2 cm ---- Increase triangularity in an attempt to make plasma less elmfree.

Plasma into rampdown

Not much change in lower triag
Sep 27 2002 11:37:12:473AM1020927010Jim IrbyDropped Tf from 4.53 to 4.4 T

RXL from .0130 to .005 --- too small a change was made on shot 009

Got lower field

Got increased lower triangularity --- but it's more elmfree?

rf was a solid 2 MW

Sep 27 2002 11:56:53:870AM1020927011Jim IrbyRXL back to 0.015

Keeping TF at 4.4

Plasma into rampdown but No h-mode

good rf --- 3 e-port trips


John Rice reports lots of moly compared to the argon level on this
shot --- cause or effect?
Sep 27 2002 12:08:46:230PM1020927012Jim IrbyReloaded 1020927007 into seg 2 --- back to 4.5 T

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

fizzle

Bz0 drifted up

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -2.0833 -16.4355 -28.1594 -27.2069
dIp/dt (kA/ms): -1.4554 -2.5724 -1.3098 0.0813
pressure (mTorr): 0.0568 0.0543 0.0536 0.0536
Bz0 (mT): -2.0630 0.0569 1.8231 16.9981
Br0 (mT): 0.1049 -0.2090 -0.6122 -0.3415
Sep 27 2002 12:32:25:713PM1020927013Jim IrbyEF4 from -1315 to -1330 Amps

Prepuff back to 29 ms

Plasma --- good h-mode again

John reports rotation drop
Sep 27 2002 12:39:06:163PM1020927014Jim IrbyRepeat

h-mode, but with brief dropout during rf trip
Sep 27 2002 01:12:30:587PM1020927015Jim IrbyEF4 to -1325 from -1330 Amps --- chase Bz0

TF to 4.7 T --- 128.653 kA

5 minutes of ecdc at 2e-4 Torr D2
Prefill from 29 to 27 ms

Plasma but several trips on E-port


Sep 27 2002 01:25:55:770PM1020927016Jim IrbyRepeat of shot 15

Plasma --- E-port trips
Sep 27 2002 01:36:59:260PM1020927017Jim Irbyincreased d-port power and reduced e-port to try and keep more constant rf

good plasma




Sep 27 2002 01:46:57:840PM1020927018Jim IrbyTF to 5.4T

Nice clean h-mode

Looks like .5 MW is the best we can do out of e-port
Sep 27 2002 02:16:22:990PM1020927019Jim IrbyIp to 600 kA; staying gat 5.4 T

plasma --- trips in d and e
Sep 27 2002 02:17:27:197PM1020927020Jim Irbyplasam --- trips in d and e

h/(h+d) 7-8%

Sep 27 2002 02:23:52:240PM1020927021Jim IrbyTry with just d-port

plasma
Sep 27 2002 02:35:08:057PM1020927022Jim IrbyTF to 4.7 T, 129kA

Prefill back to 29 ms

Plasma but pretty ratty --- bad things at crossover
Sep 27 2002 02:58:42:963PM1020927023Jim IrbyDropped Ip gain to zero around crossover time, then increased it back to normal.

Plasma into rampdown, but still have crossover problem
Sep 27 2002 03:15:31:417PM1020927024Jim IrbyTF to 4.5 T

Added 10 more ms of argon

Delayed gain increase in Ip another 20 ms

Ip may have looked a little better --- still lost inner gap

Heavy faulting on d-port too
Sep 27 2002 03:31:11:790PM1020927025Jim IrbyRepeat with some rf I hope

plasma but with very little rf

move rf timing next shot to avoid crossover
Sep 27 2002 03:44:31:410PM1020927026Jim Irbyrf on at .800 ms

Delay in rf did not reduce the faulting on d-port
e-port ran cleanly at 0.5 MW
Sep 27 2002 03:55:13:523PM1020927027Jim IrbyIp request to 650 kA
Ip gain back to 7 to 9.

No change in crossover

Only 1.4 MW of rf
Sep 27 2002 04:08:11:987PM1020927028Jim IrbyTF to 4.7 T

No h-modes

rf power low --- will raise for next shot
Sep 27 2002 04:28:21:633PM1020927029Jim Irbyrequest more rf

better --- some h-mode activity

rotation slows --- ITB forming
Sep 27 2002 06:33:31:517PM1020927030Jim Irbyattempt more rf

plasma ---- still only a little more than 1 MW rf --- multiple h-modes
Sep 27 2002 04:50:14:897PM1020927031Jim Irbyrepeat with more rf

plasma --- a little more rf early ---- multi h's
Sep 27 2002 06:32:00:590PM1020927032Jim Irbyattempt to get more rf

plasma --- multiple h-modes --- no usuable ITB

Engineering Operator Comments
ShotTimeTypeStatusComment
108:43:30:937AMTestBadEdge Analysis Jobs stuck on cmodws02 and cmodws07
209:13:37:730AMTestBadCamac Problems
309:19:39:913AMTestBadIgor Stuck Again
409:34:32:317AMTestBadIgor Stuck Again
510:06:23:880AMTestBadIgor Problems
610:22:03:813AMTestOk
710:33:07:413AMPlasmaOk
810:45:50:563AMPlasmaOk
911:04:07:427AMPlasmaOk
1011:26:31:593AMPlasmaOk
1111:39:31:853AMPlasmaOk
1212:01:32:473PMPlasmaOk
1312:14:52:540PMPlasmaOk
1412:30:29:787PMPlasmaOk
1512:53:30:723PMPlasmaOk
1601:07:12:967PMPlasmaOk
1701:22:21:060PMPlasmaOk
1801:38:16:560PMPlasmaOk
1901:51:16:537PMPlasmaOk
2002:04:07:467PMPlasmaOk
2102:17:19:383PMPlasmaOk
2202:31:26:003PMPlasmaOk
2302:51:40:230PMPlasmaOk
2403:04:33:910PMPlasmaOk
2503:18:57:080PMPlasmaOk
2603:32:07:120PMPlasmaOk
2703:46:45:680PMPlasmaOk
2803:59:40:800PMPlasmaOk
2904:12:53:403PMPlasmaOk
3004:28:37:433PMPlasmaOk
3104:42:14:270PMPlasmaOk
3204:55:32:623PMPlasmaOk