Alcator C-Mod Run 1010731 Information

Back to runs

Miniproposals
Miniproposal:293a
Date Filed: 5/10/2001
Title:QC mode/EDA study
First Author:Dmitri Mossessian
Session Leader:Dmitri Mossessian (shots 1-29)

Operators
Session leader(s):Dmitri Mossessian
Physics operator(s):Ian Hutchinson
Engineering operator(s):Bill Byford,Ed Fitzgerald

Engineering Operator Run Comment
MP293A mode frequency vs power PO:Hutch SL:Mossessian EO:Fitzgerald/Byfo

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries
Entered: Jul 7 2004 04:37:14:537PM
Author: To Be Determined
Physop Summary 1010731 MP293A

QC mode versus power.

SL Mossessian
PO Hutch

Summary
_______

Machine ran well. Keeping H/D down called for between shots ECDC.
We got 4MW RF into the plasma with the two frequencies. However, the
limit was arcing of j-port at the top, which blew away the plasma on
many occasions. Practically all disruptions are traceable to RF injections,
many of which are observable on the TV.

A few ELMy periods were obtained at the highest powers. H-factors below
2 in most cases, so these are not high performance.


Scorecard
_________
2 Fizzles. 3 null shots because of MDS/control. 24 plasmas.


Details
_______

1010731xxx hutch PHYSICS_OPERATOR Jul 31 2001 8:34:10:490AM
. . . . . . . . . . . . . . . . . . .
MP 293A QC mode vs power.

Cold start.

Ip to 1 MA.
NL04 to 1.e20
I_TF to 144kA
Load.
----------------------------------------------------------------------------
1010731001 hutch PHYSICS_OPERATOR Jul 31 2001 9:10:30:793AM
. . . . . . . . . . . . . . . . . . . .
Cycle test only. Breaker pulled before cycle.
----------------------------------------------------------------------------
1010731002 hutch PHYSICS_OPERATOR Jul 31 2001 9:42:11:670AM
. . . . . . . . . . . . . . . . . . . .
Plasma. 2.3 MW. 140kJ good EDA plasma.

Move RF start to .6s. Increase power.
----------------------------------------------------------------------------
1010731003 hutch PHYSICS_OPERATOR Jul 31 2001 10:02:18:780AM
. . . . . . . . . . . . . . . . . . . .
Plasma. 2.8 MW. 150kJ. Temperature ramps down as the shot goes on. Not
clear why.

Set gas puff during H-mode to 15 from 30. The nl04 feedback is off after
0.75s with just a sustaining V-program.
----------------------------------------------------------------------------
1010731004 hutch PHYSICS_OPERATOR Jul 31 2001 10:18:12:756AM
. . . . . . . . . . . . . . . . . . . .
Plasma. No J-port. Li pellet at 1.3s.
----------------------------------------------------------------------------
1010731005 hutch PHYSICS_OPERATOR Jul 31 2001 10:38:15:476AM
. . . . . . . . . . . . . . . . . . . .
Plasma Disrupts at .8s. Big injection at .6s
----------------------------------------------------------------------------
1010731007 hutch PHYSICS_OPERATOR Jul 31 2001 11:17:41:323AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Multiple H-L. J-port died.

ECDC between shots.
Ip to .9MA.
----------------------------------------------------------------------------
1010731008 hutch PHYSICS_OPERATOR Jul 31 2001 11:39:46:686AM
. . . . . . . . . . . . . . . . . . . .
Plasma Disrupts at 1.4s, but prior to that looks better.

Reduce Argon puff. JR had too much! Get it in writing.
----------------------------------------------------------------------------
1010731009 hutch PHYSICS_OPERATOR Jul 31 2001 11:58:22:353AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Big gas or particle injection at .4s sends shot off track.

Repeat
----------------------------------------------------------------------------
1010731010 hutch PHYSICS_OPERATOR Jul 31 2001 12:23:59:270PM
. . . . . . . . . . . . . . . . . . . .
Plasma disrupts at .75s. Killed by J-port top arc.

Take fill puff to 20ms from 24ms because DNB plans to open.
----------------------------------------------------------------------------
1010731011 hutch PHYSICS_OPERATOR Jul 31 2001 12:45:14:820PM
. . . . . . . . . . . . . . . . . . . .
Fizzle as advertized. Got 0.10 mtorr fill. Too much.

Fill puff to 15ms.
----------------------------------------------------------------------------
1010731012 hutch PHYSICS_OPERATOR Jul 31 2001 1:25:42:680PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Data lost because of MDS problem.
----------------------------------------------------------------------------
1010731013 hutch PHYSICS_OPERATOR Jul 31 2001 1:25:56:023PM
. . . . . . . . . . . . . . . . . . . .
Null shot. MDS messed up.
----------------------------------------------------------------------------
1010731014 hutch PHYSICS_OPERATOR Jul 31 2001 1:48:57:466PM
. . . . . . . . . . . . . . . . . . . .
MDS still broken.
----------------------------------------------------------------------------
1010731015 hutch PHYSICS_OPERATOR Jul 31 2001 1:56:33:690PM
. . . . . . . . . . . . . . . . . . . .
Fizzle.

Puff to 16ms.
EF4 to -1305 from -1310A.
----------------------------------------------------------------------------
1010731016 hutch PHYSICS_OPERATOR Jul 31 2001 2:27:29:526PM
. . . . . . . . . . . . . . . . . . . .
Plasma. 4MW ICRF but still having H/D rising to .1 through the RF.

Lower nl04 to .8. Puff to 15.5ms.
----------------------------------------------------------------------------
1010731017 hutch PHYSICS_OPERATOR Jul 31 2001 2:52:38:990PM
. . . . . . . . . . . . . . . . . . . .
Plasma. E-port did not come on. 2.9MW.

DNB raises their pressure by a reported 10%
Fill puff to 15ms.
ICEF4 to -1310A.
Nl04 to 0.9
----------------------------------------------------------------------------
1010731018 hutch PHYSICS_OPERATOR Jul 31 2001 3:19:54:723PM
. . . . . . . . . . . . . . . . . . . .
Plasma. 4MW. neutrons 6e13. 170 kJ.

nl04 to 1.1e20
nl04 gain to zero at .62s.
ECDC positions to rmin=44 rmax=115 r_res=90. Used to be rmax=103
rres=45.NO 115 is too far; reset to 103.
Turn off argon.
----------------------------------------------------------------------------
1010731019 hutch PHYSICS_OPERATOR Jul 31 2001 3:40:40:896PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Disrupts at .9s. Big injections prior.
----------------------------------------------------------------------------
1010731020 hutch PHYSICS_OPERATOR Jul 31 2001 4:02:31:933PM
. . . . . . . . . . . . . . . . . . . .
Plasma Disrupts at .65s. Did not survive the first injection.
J-port Top arc identified.

Fill to 14ms.
----------------------------------------------------------------------------
1010731021 hutch PHYSICS_OPERATOR Jul 31 2001 4:27:17:333PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Disrupts at .78s. Seems to be J-port again.
----------------------------------------------------------------------------
1010731022 hutch PHYSICS_OPERATOR Jul 31 2001 4:50:47:403PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Disrupts at .78s.

nl04 to 1.0e20 gas puff to 30 V during H-mode.
----------------------------------------------------------------------------
1010731023 hutch PHYSICS_OPERATOR Jul 31 2001 5:12:59:423PM
. . . . . . . . . . . . . . . . . . . .
Plasma. 3.4 MW 2e13 neutrons.
----------------------------------------------------------------------------
1010731024 hutch PHYSICS_OPERATOR Jul 31 2001 5:35:54:116PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Disrupts due to a big injection at .724s

D-port top arcs. J-port even more convincing.

ECDC r_res to 60.
----------------------------------------------------------------------------
1010731025 hutch PHYSICS_OPERATOR Jul 31 2001 6:13:30:686PM
. . . . . . . . . . . . . . . . . . . .
Plasma. 3.0MW. Survives Li pellet. 138 kJ.


Turn argon back on.
----------------------------------------------------------------------------
1010731026 hutch PHYSICS_OPERATOR Jul 31 2001 6:24:23:913PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Injection in the middle but survives.
----------------------------------------------------------------------------
1010731027 hutch PHYSICS_OPERATOR Jul 31 2001 6:46:10:136PM
. . . . . . . . . . . . . . . . . . . .
Plasma. RF fired at 1s. Trips at 1.3s with an injection. 3.9 MW.

TF current to 140kA.
----------------------------------------------------------------------------
1010731028 hutch PHYSICS_OPERATOR Jul 31 2001 7:04:42:530PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Disrupts at 1.13s. 4.7 MW before the catastrophe.

Try to increase upper triangularity by lowering ZXu to 3cm
and making RXU -3cm.
----------------------------------------------------------------------------
1010731028 hutch PHYSICS_OPERATOR Jul 31 2001 7:05:55:920PM
. . . . . . . . . . . . . . . . . . . .
Plasma disrupts at 1.17s.



Session Leader Comments
Jul 31 2001 10:01:04:950AM1010731002Dmitri MossessianGood shot. 2.3 MW of RF, starts at .7 sec, H mode starts at .78 sec

QC mode seen on PCI, probes, not reflectometer.

Max gradP ~ 1e7, average ~ 7e6.
Jul 31 2001 10:09:01:370AM1010731003Dmitri MossessianGood shot. 2.9 MW of RF, starts at .6 sec, H mode starts at .67 sec

QC mode seen on PCI, probes, not reflectometer.

GradP a little higher than on shot 2, but does not exceed 1e7.
Jul 31 2001 10:11:02:573AM1010731004Dmitri Mossessian2 H modes. 2 MW RF (no J).

gradP ~ 6e6. QC mode f~120 kHz
Jul 31 2001 10:31:02:043AM1010731005Dmitri MossessianEDA, disrupted at 0.8 s due to injection.

3.5 MW of RF, but very poor heating (injection at 0.7 s ?).
Only 150 kJ W_mhd, gradP ~ 7e6
Jul 31 2001 10:58:19:553AM1010731006Dmitri MossessianMultiple H mode, first is ELM-free.
Jul 31 2001 10:58:53:077AM1010731007Dmitri MossessianSame as shot 6. Go to 0.9 MA to get higher q and EDA.
Jul 31 2001 11:29:49:257AM1010731008Dmitri MossessianGood EDA. Steady 90 kHz QC mode.

3.5 MW RF, but heating is poor (H/D climbs up to 10% by the end
of H mode).

Max gradP ~ 8.5e6
Jul 31 2001 02:25:53:520PM1010731016Dmitri MossessianEDA with some ELMs at the beginning, when P_rad is not too high yet.

RF=4 MW. but heating efficiency not too high.
Jul 31 2001 02:58:42:833PM1010731017Dmitri MossessianVarying target density to optimize heating.

0.8e20 target for this shot. Similar to shot 16.
Jul 31 2001 02:58:54:833PM1010731018Dmitri MossessianVarying target density to optimize heating.

0.9e20 target for this shot. Similar to shot 16 and 17.
Jul 31 2001 04:37:35:560PM1010731019Dmitri MossessianVarying target density to optimize heating.

1.1e20 target for this shot. Big injection at ~.7, cold H mode follows.
Jul 31 2001 04:38:29:797PM1010731021Dmitri MossessianSimilar to 19, disrupted 100 ms after L-H
Jul 31 2001 04:38:48:280PM1010731022Dmitri MossessianSame as 21.
Jul 31 2001 04:58:44:500PM1010731023Dmitri MossessianLower n_target to 1e20, doubled puff during RF. Lower RF to 3.5 MW

Good long EDA with hints of ELMs at the beginning whenb Te_ped above 400 eV.
Injection then cools pedestal and ELMs disappear.
Jul 31 2001 05:36:06:490PM1010731024Dmitri MossessianRised RF 250 kW. Disrupted
Jul 31 2001 05:36:49:350PM1010731025Dmitri Mossessian3MW RF, long EDA
Jul 31 2001 06:14:18:640PM1010731026Dmitri Mossessian2 MW RF, injections stop EDA, but it recovers.
Jul 31 2001 06:34:47:283PM1010731027Dmitri MossessianTry 4 MW RF again, starting at 1 s.

H mode survives for 300 ms with 4 MW of RF. Max Te is 600 eV, max gradP ~ 1e7

ELMs seen while Te>400 eV

Physics Operator Comments
Jul 31 2001 08:34:10:490AMIan HutchinsonMP 293A QC mode vs power.

Cold start.

Ip to 1 MA.
NL04 to 1.e20
I_TF to 144kA
Load.
Jul 31 2001 09:10:30:793AM1010731001Ian HutchinsonCycle test only. Breaker pulled before cycle.
Jul 31 2001 09:42:11:670AM1010731002Ian HutchinsonPlasma. 2.3 MW. 140kJ good EDA plasma.

Move RF start to .6s. Increase power.
Jul 31 2001 10:02:18:780AM1010731003Ian HutchinsonPlasma. 2.8 MW. 150kJ. Temperature ramps down as the shot goes on. Not
clear why.

Set gas puff during H-mode to 15 from 30. The nl04 feedback is off after
0.75s with just a sustaining V-program.
Jul 31 2001 10:18:12:757AM1010731004Ian HutchinsonPlasma. No J-port. Li pellet at 1.3s.
Jul 31 2001 10:38:15:477AM1010731005Ian HutchinsonPlasma Disrupts at .8s. Big injection at .6s
Jul 31 2001 11:17:41:323AM1010731007Ian HutchinsonPlasma. Multiple H-L. J-port died.

ECDC between shots.
Ip to .9MA.
Jul 31 2001 11:39:46:687AM1010731008Ian HutchinsonPlasma Disrupts at 1.4s, but prior to that looks better.

Reduce Argon puff. JR had too much! Get it in writing.
Jul 31 2001 11:58:22:353AM1010731009Ian HutchinsonPlasma. Big gas or particle injection at .4s sends shot off track.

Repeat
Jul 31 2001 12:23:59:270PM1010731010Ian HutchinsonPlasma disrupts at .75s. Killed by J-port top arc.

Take fill puff to 20ms from 24ms because DNB plans to open.
Jul 31 2001 12:45:14:820PM1010731011Ian HutchinsonFizzle as advertized. Got 0.10 mtorr fill. Too much.

Fill puff to 15ms.
Jul 31 2001 01:25:42:680PM1010731012Ian HutchinsonPlasma. Data lost because of MDS problem.
Jul 31 2001 01:25:56:023PM1010731013Ian HutchinsonNull shot. MDS messed up.
Jul 31 2001 01:48:57:467PM1010731014Ian HutchinsonMDS still broken.
Jul 31 2001 01:56:33:690PM1010731015Ian HutchinsonFizzle.

Puff to 16ms.
EF4 to -1305 from -1310A.
Jul 31 2001 02:27:29:527PM1010731016Ian HutchinsonPlasma. 4MW ICRF but still having H/D rising to .1 through the RF.

Lower nl04 to .8. Puff to 15.5ms.
Jul 31 2001 02:52:38:990PM1010731017Ian HutchinsonPlasma. E-port did not come on. 2.9MW.

DNB raises their pressure by a reported 10%
Fill puff to 15ms.
ICEF4 to -1310A.
Nl04 to 0.9
Jul 31 2001 03:19:54:723PM1010731018Ian HutchinsonPlasma. 4MW. neutrons 6e13. 170 kJ.

nl04 to 1.1e20
nl04 gain to zero at .62s.
ECDC positions to rmin=44 rmax=115 r_res=90. Used to be rmax=103
rres=45.NO 115 is too far; reset to 103.
Turn off argon.
Jul 31 2001 03:40:40:897PM1010731019Ian HutchinsonPlasma. Disrupts at .9s. Big injections prior.
Jul 31 2001 04:02:31:933PM1010731020Ian HutchinsonPlasma Disrupts at .65s. Did not survive the first injection.
J-port Top arc identified.

Fill to 14ms.
Jul 31 2001 04:27:17:333PM1010731021Ian HutchinsonPlasma. Disrupts at .78s. Seems to be J-port again.
Jul 31 2001 04:50:47:403PM1010731022Ian HutchinsonPlasma. Disrupts at .78s.

nl04 to 1.0e20 gas puff to 30 V during H-mode.
Jul 31 2001 05:12:59:423PM1010731023Ian HutchinsonPlasma. 3.4 MW 2e13 neutrons.
Jul 31 2001 05:35:54:117PM1010731024Ian HutchinsonPlasma. Disrupts due to a big injection at .724s

D-port top arcs. J-port even more convincing.

ECDC r_res to 60.
Jul 31 2001 06:13:30:687PM1010731025Ian HutchinsonPlasma. 3.0MW. Survives Li pellet. 138 kJ.


Turn argon back on.
Jul 31 2001 06:24:23:913PM1010731026Ian HutchinsonPlasma. Injection in the middle but survives.
Jul 31 2001 06:46:10:137PM1010731027Ian HutchinsonPlasma. RF fired at 1s. Trips at 1.3s with an injection. 3.9 MW.

TF current to 140kA.
Jul 31 2001 07:04:42:530PM1010731028Ian HutchinsonPlasma. Disrupts at 1.13s. 4.7 MW before the catastrophe.

Try to increase upper triangularity by lowering ZXu to 3cm
and making RXU -3cm.
Jul 31 2001 07:05:55:920PM1010731028Ian HutchinsonPlasma disrupts at 1.17s.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:06:53:350AMPlasmaBadOH-2 Breaker Opened during INIT
209:24:57:957AMPlasmaOk
309:39:21:980AMPlasmaOk
409:59:14:587AMPlasmaOk
510:17:08:083AMPlasmaOk
610:35:25:970AMPlasmaOk
710:49:30:477AMPlasmaOk
811:12:04:763AMPlasmaOk
911:34:36:783AMPlasmaOk
1011:57:51:570AMPlasmaOk
1112:21:08:983PMPlasmaOk
1212:43:09:003PMPlasmaOk
1501:46:44:650PMTestOk
1602:00:02:290PMTestOk
1702:23:33:127PMPlasmaOk
1802:47:34:713PMPlasmaOk
1903:16:21:920PMPlasmaOk
2003:38:50:127PMPlasmaOk
2104:00:37:630PMPlasmaOk
2204:24:39:483PMPlasmaOk
2304:49:04:257PMPlasmaOk
2405:10:52:980PMPlasmaOk
2505:34:11:987PMPlasmaOk
2605:58:25:480PMPlasmaOk
2706:20:50:453PMPlasmaOk
2806:43:39:147PMPlasmaOk
2907:03:42:780PMPlasmaOk