Alcator C-Mod Run 1030530 Information

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Miniproposals
Miniproposal:327
Date Filed:10/11/2002
Title:Developing low ne EDA H-mode targets for LHCD
First Author:Amanda Hubbard
Session Leader:Amanda Hubbard (shots 1-34)

Operators
Session leader(s):Amanda Hubbard
Physics operator(s):Ian Hutchinson
Engineering operator(s):Ed Fitzgerald,Bill Parkin,Gary Dekow

Engineering Operator Run Comment
MP#327 Low ne EDA targets; PO Hutch; SL Hubbard; EO Dekow/Fitz/Parkin

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:32:820PM
Author: To Be Determined
Run Summary for 1030530: MP#327 Low ne EDA targets

Phys. Op: Ian Hutchinson
Session Leader: Amanda Hubbard
RF Ops: Yijun Lin, Steve Wukitch

Physics run plan:

The primary goal of this run is to complete Part B as specified in MP#327:
Increasing power, and temperature, in low density EDA H-modes so as to
demonstrate an attractive LHCD target. The run follows on the previous
successful run day on 1021106, which essentially completed Part A:
demonstrating a lower density, steady EDA H-mode at 600 kA. On that day we
were limited to 2 MW at 80 MHz.

Plan:

1) Start with 800 kA, 5.4 T, nel=9e19m-2, to demonstrate that steady EDA's can
be obtained at nominal conditions (not so evident this campaign). Moderate RF
power, ~ 2.5 MW. Discharge such as 1030516003 (or others this day) suitable
for waveforms and RF coupling.

2) Lower current to 580 kA, as on 1021106022, still with ~2.5 MW RF.
Progressively reduce target density, monitoring 'EDAness' of discharge; stop at
minimum steady density.

3) Raise RF power shot to shot, aiming for 4 MW (or maximum at which steady RF
can be maintained). It will be of interest to see
- how hot we can get the core and edge.
- whether raising Te (and therefore dropping edge collisionality) causes us to
lose EDA, and/or generate some type of ELM. Good edge TS will be important,
and it is highly desirable to have PCI and/or reflectometry available to
monitor QC mode; this should be new ground in the mode operational space.

This should not, in principle, take an entire run day (famous last words).
If there is remaining
time, or if for some reason the H-mode is not cooperating, spend remaining
discharges exploring a closely related aim: making low density, high
temperature L-mode plasmas, also a candidate LH target:

4) Make upper null discharge; 1030508013 would be a good starting point.
Add ICRF at progressively higher power to find limit of L-H threshold
(about 3.3 MW?) and also limits of power handling near upper x-point.
Scan target density and power to map out the available n-T space.

Results:

In general, we did manage to follow and complete much of the above run plan
(parts 1-3),
despite rather high H/D and radiation levels which probably impeded
performance. Shots 1-5 we ran a 5.4 T, 800 kA, moderate ne plasma, which was
not steady EDA despite some observed QC mode. Shot 6 we reloaded a previous
steady EDA discharge, 1021106001, which was much better despite nominally very
similar parameters; would be worth looking to see what the subtle differences
were! PCI was unavailable today but several reflectometer channels were
working and gave good measurements of the QC mode which was very valuable for
this run - thanks Nils.

We then started reducing Ip to 700 kA (shot 8) and 600 kA (shot 9), with RF at
3 MW. From then on we mainly varied target density (lowering it) and RF power
(raising it). Typically the first H-mode had the higher temperatures and
stored energy; after the first RF trip and/or back transition the plasma
entered a cooler, ELMy phase. Shots 12-15 are good examples; in the early
period of shot 14 edge Te exceeded 700 eV and the core 5 keV, with W=106 kJ and
H ~ 2 despite high H/D; there was a QC mode though ne was not entirely steady.
Neped was 1.3-1.4 x 10^20 m-3, good for future LH. However, there were copious
impurity injections, apparently from divertor hot spots; later strike point
tweaks seemed to fix that. Shot 15 disrupted. Shot 16 was slightly lower
density and was ELM-free with no QC mode.

For shots 18-24 target nel was slightly raised, to 6e19 m-2. This gave
steadier, more obviously EDA H-modes. Slightly cooler but still quite good
performance, with nped 1.5e20 m-3, Tped 400 eV, W=90 kJ, and Te0 3.8 keV.
All shots had clear QCmodes.

Shots 25-27 had lower density and returned to very hot, if more transient,
conditions; W=115-125 kJ. Should be a nice scan of QC mode properties.
Sighting of QC mode were reported on several shots by BES, Active MHD and FRCECE
(Bt was raised to 5.7 T on shots 24-26 to put edge channels in pedestal). ALso
possible 1.85 MHz mode on magnetics.

Shots 32-33 had nel 4.6 e19 m-2, lost the QC mode and definite ELM-free. Shot
34 returned to the target of previously 'weak EDA' shots (5e19), but with lower
RF (2.6-2 MW). H-Modes were clearly ELM-free!

All in all, we accomplished most of the goals of the run, with hot, low ne,
good confinement plasma suitable for ACCOME modelling (shots 14 and 20
good candidates for modelling). We anticipare they will show good LH
efficiency. We also got considerable data on QC mode
properties and existence space in the low ne, low Ip regime which bear further
analysis. One can anticipate that performance would be even better in these
regimes after a more recent boronization (H/D was up to 0.2 by the end of the
day, and Prad was typically rising to PRF even with QC mode); would be worth
revisiting these conditions in the future.


Physics Operator Summaries
Entered: Jul 7 2004 04:37:18:037PM
Author: To Be Determined
Physop Summary MP#327 Low ne EDA targets

PO Hutch
SL Hubbard

Summary
_______

We started with very ragged machine and RF conditions but after some
tuning obtained some fairly impressive results with H-factors of 2 at
0.6MA,and completed most of the proposal. See Session Leader for
physics.

Heating seemed effective above a temperature of about 3keV despite
there being an H/D ratio of 0.1. It seemed as if this was a non-linear
effect. At the lower end of the EDA boundary was where the performance
was best (consistent with results that date back to at least 1996). A
couple of shots without QC mode were obtained with nl04 at about
0.35e20. At nl04=0.5e20 QC mode was present although the density was
not well controlled. Radiation was significant, but there were some
signs that it could be overcome. Argon puff of 40ms inherited from a
prior shot was way too much: 25ms satisfied JR.

RF worked tolerably well with a number of sustained 4MW shots. It
killed only a handful of plasmas. Startup was excellent. One fizzle
only, which was caused by the disruption caused by interferometer
failure.

The final shot was designed as a test of whether lower power make the
plasma "more EDA". The previous observation that it is in fact the
other way around was confirmed. More RF power leads to a "more EDA"
like plasma with other settings the same.


Scorecard
_________

Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax
1 1.965 0.796 2 1.960 0.795
3 1.964 0.798 4 1.968 0.800
5 1.968 0.800 6 1.964 0.818
7 1.962 0.811 8 1.964 0.762
9 1.964 0.662 10 1.970 0.680
11 1.973 0.653 12 1.973 0.647
13 1.971 0.644 14 1.973 0.640
15 0.790 0.640 16 0.955 0.647
17 1.231 0.641 18 1.972 0.636
19 1.972 0.632 20 1.971 0.636
21 1.971 0.637 22 1.971 0.638
23 1.971 0.638 24 1.973 0.643
25 0.913 0.635 26 1.972 0.626
27 1.971 0.645 28 1.972 0.631
29 1.970 0.624 30 0.669 0.618
31 0.000 0.030 32 1.170 0.647
33 1.971 0.625 34 1.972 0.626

Finished summary for 1030530 Total of 34 shots.
34 shots. 33 plasmas. 1 fizzles. 0 duds.


Details
_______

----------------------------------------------------------------------------
1030530xxx hutch PHYSICS_OPERATOR May 30 2003 8:41:03:320AM
. . . . . . . . . . . . . . . . . . . .
Load segment 2 from 1030516003 0.8 MA single null.
Import segment 3 from yesterday. Copy A-coil programming across.
Load Clean.
----------------------------------------------------------------------------
1030530001 hutch PHYSICS_OPERATOR May 30 2003 9:23:26:346AM
. . . . . . . . . . . . . . . . . . . .
Plasma not steady eda yet.

RXL to 0 from 1cm to increase triangularity.
Rcur to .661 from .664 to increase outer gap.
----------------------------------------------------------------------------
1030530002 hutch PHYSICS_OPERATOR May 30 2003 9:37:55:326AM
. . . . . . . . . . . . . . . . . . . .
Plasma. RF trips out causing back transitions.
Bounce on startup.

EF3 voltag to 2600 from 2550 at 12ms.
J-port tripping is reported to be associated with high
neutral pressure. So reduce nl04 to .75 to reduce it.
----------------------------------------------------------------------------
1030530004 hutch PHYSICS_OPERATOR May 30 2003 10:02:53:490AM
. . . . . . . . . . . . . . . . . . . .
Plasma.

EF3 Voltage to 2650.
Lower nl04 some more to .71
----------------------------------------------------------------------------
1030530004 hutch PHYSICS_OPERATOR May 30 2003 10:14:33:790AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Solved the bounce problem.
Working on prad main. Brian Y fixes a bug in program.

No changes
----------------------------------------------------------------------------
1030530005 hutch PHYSICS_OPERATOR May 30 2003 10:25:25:626AM
. . . . . . . . . . . . . . . . . . . .
Plasma

Load 1021106001 seg 2 to seg2
Fiddle with bolofeed.
Set a-coil trace correctly.
----------------------------------------------------------------------------
1030530006 hutch PHYSICS_OPERATOR May 30 2003 10:39:09:810AM
. . . . . . . . . . . . . . . . . . . .
Looks better, but there are type III elms.
RF stayed on.
----------------------------------------------------------------------------
1030530007 hutch PHYSICS_OPERATOR May 30 2003 10:57:02:130AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Repeated shot 6 quite well.


Ip to 0.7MA.
----------------------------------------------------------------------------
1030530008 hutch PHYSICS_OPERATOR May 30 2003 11:09:40:570AM
. . . . . . . . . . . . . . . . . . . .
Plasma

OH1V to 150V from 250V at .15s.
Ip to .6MA
Argon puff to 25ms from 40ms.
Load
----------------------------------------------------------------------------
1030530009 hutch PHYSICS_OPERATOR May 30 2003 11:26:12:733AM
. . . . . . . . . . . . . . . . . . . .
Plasma

Fill puff to 24ms.
OH1V to 150 at .3s
nl04 to .6 from .8
----------------------------------------------------------------------------
1030530010 hutch PHYSICS_OPERATOR May 30 2003 11:38:47:923AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Sustained H mode.


OH1V to 100V at .15s
NL04 to .5
----------------------------------------------------------------------------
1030530011 hutch PHYSICS_OPERATOR May 30 2003 12:24:56:130PM
. . . . . . . . . . . . . . . . . . . .
Plasma. This shot really heated till the RF tripped.
----------------------------------------------------------------------------
1030530014 hutch PHYSICS_OPERATOR May 30 2003 12:35:09:436PM
. . . . . . . . . . . . . . . . . . . .
Good plasma till an injection at .74s.
----------------------------------------------------------------------------
1030530015 hutch PHYSICS_OPERATOR May 30 2003 12:53:07:003PM
. . . . . . . . . . . . . . . . . . . .
Plasma disrupts at .79 after an injection at .73.
This very similar result. We see hot spot in the divertor
that explodes into the plasma. 4.4MW with good performance
prior to injection.

No pcs changes. Lower power.
----------------------------------------------------------------------------
1030530016 hutch PHYSICS_OPERATOR May 30 2003 1:08:45:840PM
. . . . . . . . . . . . . . . . . . . .
Plasma Disrupts at .94s.

Move rxl to .013 from .011 to try to put the strike point higher
up the plate.
----------------------------------------------------------------------------
1030530017 hutch PHYSICS_OPERATOR May 30 2003 1:25:11:133PM
. . . . . . . . . . . . . . . . . . . .
Plasma till 1.2s.

nl04 to .55
----------------------------------------------------------------------------
1030530018 hutch PHYSICS_OPERATOR May 30 2003 1:44:40:290PM
. . . . . . . . . . . . . . . . . . . .
Full length shot.

nl04 to .6
Raise zxl 0.5cm.
----------------------------------------------------------------------------
1030530019 hutch PHYSICS_OPERATOR May 30 2003 2:20:00:723PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Got rid of injections but it is not clear whether
that is because of the strike-point tweaks or density
increase or lower RF.

No pcs changes.
----------------------------------------------------------------------------
1030530020 hutch PHYSICS_OPERATOR May 30 2003 2:20:09:960PM
. . . . . . . . . . . . . . . . . . . .
Plasma
----------------------------------------------------------------------------
1030530021 hutch PHYSICS_OPERATOR May 30 2003 2:20:16:926PM
. . . . . . . . . . . . . . . . . . . .
Plasma
----------------------------------------------------------------------------
1030530022 hutch PHYSICS_OPERATOR May 30 2003 2:20:23:210PM
. . . . . . . . . . . . . . . . . . . .
Plasma
----------------------------------------------------------------------------
1030530023 hutch PHYSICS_OPERATOR May 30 2003 2:44:05:840PM
. . . . . . . . . . . . . . . . . . . .
Plasma

TF current to 157 kA.
Supposed to be for the heterdyne ECE data.
----------------------------------------------------------------------------
1030530024 hutch PHYSICS_OPERATOR May 30 2003 2:55:50:253PM
. . . . . . . . . . . . . . . . . . . .
Plasma.

EF3V to 2700 at 12ms.
nl04 to 5 from 6.
----------------------------------------------------------------------------
1030530025 hutch PHYSICS_OPERATOR May 30 2003 3:15:54:580PM
. . . . . . . . . . . . . . . . . . . .
Disrupts at .91s. This is caused by fireworks in the
top left of j-port.

nl04 to ..55
----------------------------------------------------------------------------
1030530026 hutch PHYSICS_OPERATOR May 30 2003 3:27:40:256PM
. . . . . . . . . . . . . . . . . . . .
Plasma. H-factor=2 in this shot. Very hot and see a
QC mode, but density still rising.

I-TF to 148kA
----------------------------------------------------------------------------
1030530027 hutch PHYSICS_OPERATOR May 30 2003 3:40:19:913PM
. . . . . . . . . . . . . . . . . . . .
Plasma similar. RF stays on.

Fill puff to 27ms.
nl04 to .5
----------------------------------------------------------------------------
1030530028 hutch PHYSICS_OPERATOR May 30 2003 4:10:54:046PM
. . . . . . . . . . . . . . . . . . . .
Plasma. quite good. RF trips after first.


nl04 to .45
----------------------------------------------------------------------------
1030530030 hutch PHYSICS_OPERATOR May 30 2003 4:19:17:170PM
. . . . . . . . . . . . . . . . . . . .
Killed by interferometer running amok.

Go to preprogrammed gas.
----------------------------------------------------------------------------
1030530031 hutch PHYSICS_OPERATOR May 30 2003 4:40:35:243PM
. . . . . . . . . . . . . . . . . . . .
Fizzle.
----------------------------------------------------------------------------
1030530032 hutch PHYSICS_OPERATOR May 30 2003 4:51:55:360PM
. . . . . . . . . . . . . . . . . . . .
Plasma got nl04=.36, ELM free. J-port blows us away
at 1.17s.


Raise gas program to 25 from 17.
----------------------------------------------------------------------------
1030530033 hutch PHYSICS_OPERATOR May 30 2003 5:02:23:866PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Did not disrupt but we still got a low
density and apparently ELM free.

Reload segment 2 from shot 27.
----------------------------------------------------------------------------
1030530034 hutch PHYSICS_OPERATOR May 30 2003 5:07:24:073PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Supposed to be a repeat of the nl04=0,5 shot with lower power.
Mossessian says this will be MORE EDA. I say it will be less EDA.
And I AM RIGHT!!!

Session Leader Comments
May 30 2003 09:04:38:060AMAmanda HubbardPhysics run plan for 1030530 MP#327 Low ne EDA targets

The primary goal of this run is to complete Part B as specified in MP#327:
Increasing power, and temperature, in low density EDA H-modes so as to
demonstrate an attractive LHCD target. The run follows on the previous
successful run day on 1021106, which essentially completed Part A:
demonstrating a lower density, steady EDA H-mode at 600 kA. On that day we
were limited to 2 MW at 80 MHz.

Plan:

1) Start with 800 kA, 5.4 T, nel=9e19m-2, to demonstrate that steady EDA's can
be obtained at nominal conditions (not so evident this campaign). Moderate RF
power, ~ 2.5 MW. Discharge such as 1030516003 (or others this day) suitable
for waveforms and RF coupling.

2) Lower current to 580 kA, as on 1021106022, still with ~2.5 MW RF.
Progressively reduce target density, monitoring 'EDAness' of discharge; stop at
minimum steady density.

3) Raise RF power shot to shot, aiming for 4 MW (or maximum at which steady RF
can be maintained). It will be of interest to see
- how hot we can get the core and edge.
- whether raising Te (and therefore dropping edge collisionality) causes us to
lose EDA, and/or generate some type of ELM. Good edge TS will be important,
and it is highly desirable to have PCI and/or reflectometry available to
monitor QC mode; this should be new ground in the mode operational space.

This should not, in principle, take an entire run day (famous last words).
If there is remaining
time, or if for some reason the H-mode is not cooperating, spend remaining
discharges exploring a closely related aim: making low density, high
temperature L-mode plasmas, also a candidate LH target:

4) Make upper null discharge; 1030508013 would be a good starting point.
Add ICRF at progressively higher power to find limit of L-H threshold
(about 3.3 MW?) and also limits of power handling near upper x-point.
Scan target density and power to map out the available n-T space.
May 30 2003 09:14:27:477AM1030530001Amanda HubbardGood shot, 780 kA, 5.4 T, target nel 10^20 m-2. 2.8 MW RF, only a few trips.

However, get multiple H-Modes, not apparently EDA.
May 30 2003 09:27:32:807AM1030530002Amanda Hubbard H-modes still seem distinctly ELM-free. Several back-transitions, some possible correlated with RF trips.

Retune and try again.
May 30 2003 09:49:25:020AM1030530003Amanda HubbardSomewhat better, D alpha showing signs of rising. But, so are ne and Prad, multiple H-modes.
May 30 2003 10:33:19:747AM1030530004Amanda Hubbard Still multiple H-modes, with high Prad and RF trips.
May 30 2003 10:19:16:483AM1030530005Amanda HubbardFirst h-mode looks OK, until RF trips. But, Prad still high, and rising.

Next, reload shot 1021106001, a nice EDA with nominally similar parameters.
May 30 2003 10:33:01:763AM1030530005Amanda HubbardStill multiple H-modes, with high Prad and RF trips.
May 30 2003 10:32:05:313AM1030530006Amanda Hubbard
Reloaded shot 1021106001, a nice EDA with nominally similar parameters.

Much better, started out as decent EDA! First RF trip results in Type III ELMs for the rest of the shot,
presumably due to high Prad.
May 30 2003 10:47:06:370AM1030530007Amanda HubbardRemarkably similar to shot 6, down to the RF trip.

This may be as good as it gets, so go down to 700 kA for next shot.

May 30 2003 11:01:09:747AM1030530007Amanda Hubbard700 kA. H-mode looks quite similar, starting EDA but with rising ne and Prad. This time, reverts to ELMs before the first
RF trip.


Go to 600 kA for next shot.
May 30 2003 11:32:54:250AM1030530010Amanda Hubbard600 kA. Looks better, if not great; Nils sees a QC mode through most of the H-mode.
nel 0.7-1.22e20, nebar steady at 2e20 m-3. ne95~ 1.7e20
May 30 2003 11:49:26:057AM1030530011Amanda HubbardGoot shot. Definite QC mode. First period has very high Te's. Evidence of some MHD just before the trip.

Leave plasma alone, retry RF.
May 30 2003 12:15:04:467PM1030530012Amanda HubbardSeries of H-modes, first looks ELM-free, latter ones more EDAish.
How3ever, QC mode seen on reflectometer on all of them.

Getting very high Te (4 keV) and W (96 kJ). H-factors ~ 2.

Keep this plasma, increase power.
May 30 2003 12:15:51:370PM1030530012Amanda HubbardSimilar series of H-modes, 3 MW RF.
Getting very high Te (4.7 keV) and W (108 kJ).
May 30 2003 12:16:40:227PM1030530013Amanda HubbardSimilar series of H-modes, 3 MW RF.
Getting very high Te (4.7 keV) and W (108 kJ). HOwever, this is transient; Prad gets to 3 MW, ending
the first H-mode.
May 30 2003 12:32:54:783PM1030530014Amanda HubbardGood shot. First H-mode looks pretty good, steady edge Te, until big injection at 0.739 secs.

3.4 MW RF, pretty steady. 4.4 keV Te0, 106 Kj.
repeat, pushing up Prf and hoping for no injection.
May 30 2003 12:47:36:377PM1030530014Amanda Hubbard
4.4 MW RF, Starts off well until first RF trip, followed shortly thereafter by a big injection
from divertror region, 5.2 keV Te0, 124 Kj.
repeat, lowering Prf and hoping harder for no injection.
May 30 2003 12:48:05:750PM1030530015Amanda Hubbard
4.4 MW RF, Starts off well until first RF trip, followed shortly thereafter by a big injection
from divertror region, 5.2 keV Te0, 124 Kj.
repeat, lowering Prf and hoping harder for no injection.
May 30 2003 01:05:25:960PM1030530016Amanda Hubbard
This H-mode was more ELM-free, no clear QC mode and ne, Prad rising. Density at LH trasnsition a bit lower,
though target was the same; perhaps RF is now outgassing less.

Discharge again killed by a big injection.

3.4 MW, but still Te0 5.2 keV, Te9 690 eV, 108 kJ. Nel 5.6-9.6e19 m-2.
May 30 2003 01:17:03:447PM1030530017Amanda HubbardSeries of H-modes, not very steady. Disrupts ~ 1.2 secs.

3.1 MW, with some trips.
Te0 4.3 keV, Te9 520 eV, rises then cools. 93 kJ.
May 30 2003 01:28:23:470PM1030530018Amanda HubbardSeries of H-modes, not very steady. No disruption, but a series of injections taking a bite out of edge Te.
3.3 MW, with many trips.
Te0 4.2 keV, Te9 510 eV, rises then cools. 91 kJ.

Next shot raise nel target a bit more.
May 30 2003 01:44:07:417PM1030530019Amanda HubbardHigher target ne, Series of more EDA H-modes.
Te0 3.4 keV, Te9 400 eV, rises then cools. 78 kJ.

Next shot raise RF power.
May 30 2003 01:56:19:233PM1030530020Amanda HubbardFirst H-mode looks very nice and steady. 3.7 MW, 1.1e20 m-2, presumed EDA.
Te0 3.8 keV, Te9 420 eV 90 kJ.
Prad ~ steady at 2 MW.
Next shot raise RF power some more.
May 30 2003 02:10:58:260PM1030530021Amanda HubbardGood shot - plasma is stedy when the RF is (esp ~ 0.8-1.0 secs)
First H-mode looks very nice and steady. 34.2 MW, 1.1e20 m-2, presumed EDA.
Te0 3.8 keV, Te9 390 eV 84 kJ. Prad ~ steady at 1.6 MW.
Try again, hopefully avoiding early RF trips.
May 30 2003 02:33:02:443PM1030530023Amanda HubbardRather similar. Decent EDA but still a lot of trips on J-port.
3.7 MW.

Next shot, raise Bt to 5.7 T so FRECE can see QC mode.
May 30 2003 02:55:32:410PM1030530024Amanda Hubbard5.7 T. Still a lot of trips, still looks EDA.

next shot, give in to Ian and go back down in nel- taget (to 5e19 m-2), see if ELM-free and/or injections return, and if
W goes back up.
May 30 2003 03:04:35:890PM1030530025Amanda HubbardInjections do return, with a vengeance.

Go to intermediate ne, 5.5e20 m-2
May 30 2003 03:18:53:543PM1030530026Amanda HubbardMuch better, First H-mode gets 120 kJ, 5.8 keV. QC mode seen, though ne rising.

TS sees Tped 500 eV. ECE sees 5.8 kev.

Next shot back to 5.4 T.
May 30 2003 03:45:48:840PM1030530027Amanda HubbardGood shot - 4 MW for long period. Early phase gets very hot. QC mode seen, ne not so steady.
lowe ne for next shot.
115 kJ, Te8 800 eV.
May 30 2003 03:49:04:973PM1030530028Amanda HubbardGood shot quite similar to 27
- 4 MW for long period. Early phase still very hot. QC mode seen, ne not so steady.
lowe ne for next shot.
115 kJ, Te8 800 eV.
No evident injections, though Prad gets near to 3 MW in first H-mode.
May 30 2003 04:18:27:860PM1030530029Amanda HubbardNot very different, despite lower nel target. More RF trips.
Lower power for next shot, try for steadier.

Te8~700 eV, not steady.

Nils reports still a nice QC mode on several reflectometer channels.
Need to go lower in ne....
May 30 2003 04:16:41:800PM1030530030Amanda HubbardDisrupts early due to TCI feedback failure, ne runaway.

May 30 2003 04:41:35:977PM1030530032Amanda HubbardLow target density
nel 4.6e19 at L-H, up to 9e19 m-2.
First H-mode is definitely ELM-free, not a hint of QC mode.
Next shot, up in ne a bit. Te9 transiently 680 eV. But, RF trips early and often.
May 30 2003 05:07:01:793PM1030530033Amanda HubbardStill very low target density nel 4.6e19 at L-H, up to 9e19 m-2.
Series of ELM-free H-modes. RF better, 3.7 MW.

For final shot, return to nel target of 5e19 (as on 27, 28), but use lower PRF ~ 2.5 MW.
Dmitri predicts we will see 'more EDA' plasma. We'll see.
May 30 2003 05:07:39:917PM1030530034Amanda HubbardHIgher target density, same as shots 27,28, Lower RF.
Definitely ELM-free!

Physics Operator Comments
May 30 2003 08:41:03:320AMIan HutchinsonLoad segment 2 from 1030516003 0.8 MA single null.
Import segment 3 from yesterday. Copy A-coil programming across.
Load Clean.
May 30 2003 09:23:26:347AM1030530001Ian HutchinsonPlasma not steady eda yet.

RXL to 0 from 1cm to increase triangularity.
Rcur to .661 from .664 to increase outer gap.
May 30 2003 09:37:55:327AM1030530002Ian HutchinsonPlasma. RF trips out causing back transitions.
Bounce on startup.

EF3 voltag to 2600 from 2550 at 12ms.
J-port tripping is reported to be associated with high
neutral pressure. So reduce nl04 to .75 to reduce it.
May 30 2003 10:02:53:490AM1030530004Ian HutchinsonPlasma.

EF3 Voltage to 2650.
Lower nl04 some more to .71
May 30 2003 10:14:33:790AM1030530004Ian HutchinsonPlasma. Solved the bounce problem.
Working on prad main. Brian Y fixes a bug in program.

No changes
May 30 2003 10:25:25:627AM1030530005Ian HutchinsonPlasma

Load 1021106001 seg 2 to seg2
Fiddle with bolofeed.
Set a-coil trace correctly.
May 30 2003 10:39:09:810AM1030530006Ian HutchinsonLooks better, but there are type III elms.
RF stayed on.
May 30 2003 10:57:02:130AM1030530007Ian HutchinsonPlasma. Repeated shot 6 quite well.


Ip to 0.7MA.
May 30 2003 11:09:40:570AM1030530008Ian HutchinsonPlasma

OH1V to 150V from 250V at .15s.
Ip to .6MA
Argon puff to 25ms from 40ms.
Load
May 30 2003 11:26:12:733AM1030530009Ian HutchinsonPlasma

Fill puff to 24ms.
OH1V to 150 at .3s
nl04 to .6 from .8
May 30 2003 11:38:47:923AM1030530010Ian HutchinsonPlasma. Sustained H mode.


OH1V to 100V at .15s
NL04 to .5
May 30 2003 12:24:56:130PM1030530011Ian HutchinsonPlasma. This shot really heated till the RF tripped.
May 30 2003 12:35:09:437PM1030530014Ian HutchinsonGood plasma till an injection at .74s.
May 30 2003 12:53:07:003PM1030530015Ian HutchinsonPlasma disrupts at .79 after an injection at .73.
This very similar result. We see hot spot in the divertor
that explodes into the plasma. 4.4MW with good performance
prior to injection.

No pcs changes. Lower power.
May 30 2003 01:08:45:840PM1030530016Ian HutchinsonPlasma Disrupts at .94s.

Move rxl to .013 from .011 to try to put the strike point higher
up the plate.
May 30 2003 01:25:11:133PM1030530017Ian HutchinsonPlasma till 1.2s.

nl04 to .55
May 30 2003 01:44:40:290PM1030530018Ian HutchinsonFull length shot.

nl04 to .6
Raise zxl 0.5cm.
May 30 2003 02:20:00:723PM1030530019Ian HutchinsonPlasma. Got rid of injections but it is not clear whether
that is because of the strike-point tweaks or density
increase or lower RF.

No pcs changes.
May 30 2003 02:20:09:960PM1030530020Ian HutchinsonPlasma
May 30 2003 02:20:16:927PM1030530021Ian HutchinsonPlasma
May 30 2003 02:20:23:210PM1030530022Ian HutchinsonPlasma
May 30 2003 02:44:05:840PM1030530023Ian HutchinsonPlasma

TF current to 157 kA.
Supposed to be for the heterdyne ECE data.
May 30 2003 02:55:50:253PM1030530024Ian HutchinsonPlasma.

EF3V to 2700 at 12ms.
nl04 to 5 from 6.
May 30 2003 03:15:54:580PM1030530025Ian HutchinsonDisrupts at .91s. This is caused by fireworks in the
top left of j-port.

nl04 to ..55
May 30 2003 03:27:40:257PM1030530026Ian HutchinsonPlasma. H-factor=2 in this shot. Very hot and see a
QC mode, but density still rising.

I-TF to 148kA
May 30 2003 03:40:19:913PM1030530027Ian HutchinsonPlasma similar. RF stays on.

Fill puff to 27ms.
nl04 to .5
May 30 2003 04:10:54:047PM1030530028Ian HutchinsonPlasma. quite good. RF trips after first.


nl04 to .45
May 30 2003 04:19:17:170PM1030530030Ian HutchinsonKilled by interferometer running amok.

Go to preprogrammed gas.
May 30 2003 04:40:35:243PM1030530031Ian HutchinsonFizzle.
May 30 2003 04:51:55:360PM1030530032Ian HutchinsonPlasma got nl04=.36, ELM free. J-port blows us away
at 1.17s.


Raise gas program to 25 from 17.
May 30 2003 05:02:23:867PM1030530033Ian HutchinsonPlasma. Did not disrupt but we still got a low
density and apparently ELM free.

Reload segment 2 from shot 27.
May 30 2003 05:07:24:073PM1030530034Ian HutchinsonPlasma. Supposed to be a repeat of the nl04=0,5 shot with lower power.
Mossessian says this will be MORE EDA. I say it will be less EDA.
And I AM RIGHT!!!

Engineering Operator Comments
ShotTimeTypeStatusComment
109:02:26:973AMPlasmaOk
209:17:20:843AMPlasmaOk
309:33:16:807AMPlasmaOk
409:46:29:090AMPlasmaOk
510:03:28:253AMPlasmaOk
610:19:41:060AMPlasmaOk
710:35:33:103AMPlasmaOk
810:48:59:977AMPlasmaOk
911:04:02:897AMPlasmaOk
1011:18:44:893AMPlasmaOk
1111:32:15:283AMPlasmaOk
1211:51:58:393AMPlasmaOk
1312:07:41:890PMPlasmaOk
1412:20:26:593PMPlasmaOk
1512:33:11:970PMPlasmaBadPF breaker opened during the shot
1612:50:18:197PMPlasmaBadPF breaker open during shot
1701:03:25:027PMPlasmaOk
1801:17:04:917PMPlasmaOk
1901:31:05:837PMPlasmaOk
2001:45:16:460PMPlasmaOk
2102:00:17:397PMPlasmaOk
2202:13:12:553PMPlasmaOk
2302:25:55:493PMPlasmaOk
2402:39:01:820PMPlasmaOk
2502:53:17:867PMPlasmaOk
2603:07:24:897PMPlasmaOk
2703:21:56:817PMPlasmaOk
2803:39:00:137PMPlasmaOk
2903:52:12:810PMPlasmaOk
3004:04:46:373PMPlasmaOk
3104:17:58:547PMPlasmaOk
3204:30:43:563PMPlasmaOk
3304:44:58:220PMPlasmaOk
3405:00:19:183PMPlasmaOk