Alcator C-Mod Run 950503 Information

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Miniproposals
Miniproposal:080
Date Filed: 1/20/1995
Title:Effect of Separatrix strike point location on divertor detachment
First Author:Bruce Lipschultz
Session Leader:Bruce Lipschultz (shots 1-33)

Operators
Session leader(s):Bruce Lipschultz
Physics operator(s):Ian Hutchinson
Engineering operator(s):Frank Silva,Joe Daigle,Vinny Bertolino

Engineering Operator Run Comment
blip/hutch

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:13:647PM
Author: To Be Determined
Run 950503

Engineering operator: F. Silva
Physics operator: I. Hutchinson
Session leader: BLip

Mini proposal # 80: Effect of Separatrix strike point location on divertor
detachment.

We formed flat-plate divertor plasmas
where the separatrix strike points are above the inner and outer divertor
noses. Because there are so few probes above the divertor nose we swept
the strike point across probes that are located there at constant density in
order to obtain plasma profiles at the divertor surface.
Using this basic divertor geometry we raised the density (shot to shot)
and obtained the divertor parameters for comparison with the more standard
operation - vertical plate divertor. In particular we found that the threshold
for detachment (pressure not constant along a flux surface) was significantly
higher for the flat-plate divertor than for operation with the
vertical plate. The threshold was of order 2-2.2e20 for nl04.
This compares to the vertical plate where the threshold is more
typically 1.2-1.3e20.
The bolometric data supported this conclusion.
In addition, when the x-point was swept far from the inner divertor
the peak in the inner divertor radiation moved to the strike point
from above the inner divertor nose. There was an
anticorrelation of this movement with movement of the peak in the
C-II radiation as measured by the Chromex spectrograph.
In terms of operation we found that the flat-plate divertor was very
tricky to operate. We had problems, particularly athigh densities with the
power supplies 'railing' and the plasma going unstable. In the end it
was important, while using the STRKPSI controller not to use RXL or ZXL in any
high gain fashion. We also found that operating the plasma below the midplane
exacerbated the problems. More information is available in the PhysOp log.
The run summary follows:

shot 1: disrupted midway through shot

shot 2: This one made it all the way through. We still do not have STRKPSI
control but the separatrix is near probe 8. nl04=1.e20 during flattop.

shot 3: Sweep initiated, more work to be done in this area but good start.
nl04=1.0e20. no FSP scan yet.

shot 4: We have shortened up the period of the sweep. It starts at .65
seconds and ends at .95 seconds. The 'peak' is at .8 seconds.
nl04=0.6 e20. Sweep is not far enough. Next several shots will be
spent optimizing sweep before increasing density.

shot 5: Big injection at .87 seconds. The sweep carries probe 8 into the
private flux region this shot. Sweep looks good as far as ther divertor
plate is concerned. We are going to try to modify the x-point sweep
slightly so that the separatrix position in front of the probe doesn't
move so far. nl04=0.6e20.

shot 6: Added ZXL sweep such that FSP scanning location is fairly
constant. Probe 9 has returned to service for now and we are extending
the 'peak' in the sweep at .8 seconds to make use of it.

shot 7: The sweep seems pretty well set. By the way, in sweeping the
strike point up and down the plate RXL sweeps by almost 6 cm and ZXL by
3 cm. Next shot we will try for FSP scan.

shot 8: FSP scan just fine. We have decided to move the whole sweep farther
up the plate for the next shot.

shot 9: We have just noticed that when the sweep reaches above the nose
that the Mo Monitor registers an increase in Mo in the main plasma. This
was true last shot but doesn't to be true this shot.
Big injection at .6 seconds. no probe scan. nl04=1.e20.

shot 10: nl04=1.e20. Probe 9 worked this shot! Sweep went well and we
got a FSP scan.

shot 11: FSP scan ok. nl04=1.4e20 (with variations as the strike point sweeps).
probe 9 not alive for this shot.

shot 12: density did not quite make it to the desired value of
nl04=1.8e20. It ramps from 1.5 - 1.8 during the strike point sweep.
Probe scan marginal. We will repeat this shot with more gas. Still attached.

shot 13: nl04 = 1.6 - 1.8e20. FSP scan ok. still not detached.

shot 14: disruption at .81 seconds with density at nl04=2.e20. Power
supply problem associated with fast sweep of the strike point. First
FSP scan at .625 seconds went but the second at .825 seconds did not.
Probe 9 worked for this shot.

shot 15: Disruption again - .88 seconds. Two strikes and the 'run is over'.
We will look to see if anything can be salvaged. no FSP scan, nl04 =
1.7 - 1.8e20.

shot 16: no sweep, strike point on probe 5 or so. nl04=1.1e20. probe 9 ok.

shot 17: some sweep back. Barely reaches probe 8. No FSP scan.
nl04=1.0e20. Probe 9 ok.

shot 18: sweep increased. nl04=1.0e20. no FSP. Probe 9 ok.

shot 19: nl04= 1.5e20, no FSP scan. Things are still ok with power supplies.
Probe 9 ok.

shot 20: nl04=1.7e20, fsp scan ok, sweep ok. Still looks attached. Probe 9 ok.

shot 21: nl04=1.7e20. Still attached. FSP scan and probe 9 working.

shot 22: nl04=1.75e20. FSP scan of and Probe 9 ok.

shot 23: some evidence of detachment just outside the separatrix on this
shot. Probe 9 data, no fsp.

shot 24: The plasma center is shifted up to -1.0 cm. This seems to
improve the power supply situation. no fsp scan, probe 9 working. There
may be some small amount of detachment (extent 1 mm) shown on probe 8
at these densities (nl04=1.7e20).

shot 25: Plasma center up another 0.5 cm with positive results. no
FSP scan and probe 9 ok. detachment possibly in region of separatrix.

shot 26: fizzle

shot 27: plasma vertically centered, FSP scan and probe 9 ok. Again,
possible detachment showing on probe 8 in region of separatrix. nl04=1.7e20.
It appears that the possible detachment near the separatrix
is a 'dr' or death ray for this shot.

shot 28: nl04=2.0, sweep reduced slightly which helps the power supplies.
probe 9 ok. no probe scan this shot?

shot 29: fsp scan at nl04=2.e20. probe 9 ok. Still appears that there
is no detachment

shot 30: nl04 = 1.9 - 2.3e20 during sweep. fsp scan and probe 9 ok.
Evidence of detachment on probe 9 ( far out in the SOL), not on probe 8.

shot 31: disruption at .6 seconds due to density feedback problem.

shot 32: nl04=2.1e20, just barely made it after the previous shot's disruption.
fsp scan ok and probe 9 ok. Definate detachment on probe 8 in region of
rho = 1- 2.5 mm.

shot 33: nl04 ramping from 2 to 2.6e20 during strike point sweep. fsp
scan and probe 9 ok. There does seem to be detachment on this shot,
again the region of 2 mm outside the separatrix (perhaps further out
as well). One must note that over the period between the the strike
point moving from probe 8 to probe 9 the density rises by a significant
amount ( 2-2.6e20). This might explain the difference in detachment
measured by probes 8 & 9.


Physics Operator Summaries
Entered: Jul 7 2004 04:36:54:113PM
Author: To Be Determined
Physop summary 950503

Horizontal Plate Divertor Configuration. Higher Density.

PO: Hutch
EO: Bertolino/Daigle
SL: Blip

Overview
________

Things went reasonably well using a rapid ramp of STRKPSI till we got
a disruption "OUT" on shot 15 due to OH2L voltage limiting at about 65V.
Then we stopped that approach, in conformance with the standing orders.
Instead, after restablishing a standard plasma, the strkpsi was moved out
slowly during the shot. Density was eventually raised back up to 2.5e20,
watching the voltage limits like a hawk. The only disruption we had after
our "OUT" was caused by density feedback failure on shot 31. Halo currents
were low on it.

Operational things we learnt.
_____________________________

1. EF1L limit is now about 250V. EF1U ~200V. OH2L is about 65V.
2. Running the flat plate plasmas tends to push these to their voltage
rails at high density. OH2 is the present critical factor, but not by a lot.
3. Disruptions in this limit are particularly dangerous w.r.t halo currents.
4. About 5V OH2L is gained by running the plasma a ZCUR=0 rather than -1.5cm.
5. Contrary to previous rumor, resistive drop in the OH2 circuit is NOT
negligible. It can easily be 20V (~1.5mohm) out of a PS limit of 65V. (Or
out of ~27V for loop voltage of 1V.)

Engineering.
___________

There is still a significant problem with the OH2 voltages.

Looked at 950127017 which was a flat-plate high-density shot.
The compare-volts scope shows that OH2L gave 70V at .75s on that shot.
Also EF1s were giving 200V. Today we got 65V and 260V.
Conclusion: Power Supply "improvements" since 27 Jan 95 degraded the
voltage capability of OH2 and EF1. This week's alternator upgrade
succeeded in bringing EF1s to a level better than its January performance.
It DID NOT succeed in significantly improving the OH2L performance beyond
the January performance.
We badly need the OH2s to give at least 100V.

Looked in 950502004, the Tuesday shot, to find out effective resistance of
the OH2s. At 10kA flat current test, they show 13V L, 18V U. This proves that
the resistance is NOT negligible at the 20V level.

Scorecard
_________
Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax
1 0.469 0.851 2 1.513 0.838
3 1.527 0.835 4 1.561 0.833
5 1.453 0.838 6 1.572 0.841
7 1.582 0.843 8 1.584 0.843
9 1.532 0.833 10 1.547 0.833
11 1.495 0.833 12 1.447 0.830
13 1.451 0.825 14 0.812 0.820
15 0.900 0.823 16 1.503 0.828
17 1.520 0.830 18 1.530 0.830
19 1.454 0.830 20 1.450 0.828
21 1.429 0.825 22 1.425 0.825
23 1.422 0.823 24 1.423 0.825
25 1.417 0.825 26 0.000 0.055
27 1.426 0.828 28 1.392 0.825
29 1.394 0.830 30 1.330 0.823
31 0.601 0.866 32 1.306 0.823
33 1.262 0.823
Finished summary for 950503 Total of 33 shots.
33 shots. 33 plasmas. 0 fizzles. 0 duds.
Fizzle = gt 17 lt 50kA.

Details
_______

Load Shot 950426026.
Reprogram Density.
Load Wire 12 from 950202035. Its gains are 8.5, 1.5 (P,I). It has keywords:
RSOUT=.6144,ZSOUT=-.4367.
This is right at the nose. Set its gains to zero initially.
Change the controller keywords to put the reference at the same point.
It was (.626,-.55) which is at the bottom of the vertical plate. Now:
RSOUT=.6144,ZSOUT=-.4367,
ALL=['PSI0','RCUR','ZCUR','CLEARIN','STRKPSI','RXU','ZXU']
Called the algorithms got the following controller:
Voltage Controller*1.E3 before time-constant scaling.
1 constraint(s) 1 major constraint(s).
Major Parameters: PSI0 RCUR ZCUR
Current and Voltage limits:
15000. 15000. 10000. 10000. 22000. 5000. 50000. 50000. 50000.
400. 400. 350. 350. 3650. 1050. 900. 200. 200.
Time constant(s) in voltage optimization 100.000 ms.
PSI0 RCUR ZCUR CLEARIN STRKPSI RXU ZXU Cnstr...
0.326 -0.197 0.393 -0.045 0.135 0.120 -0.513 -0.634
0.326 -0.197 -0.393 0.608 3.524 0.088 0.164 4.473
0.175 -0.045 0.284 0.595 0.429 0.298 0.483 4.451
0.175 -0.046 -0.284 -0.107 1.789 -0.093 -0.216 -0.930
1.871 2.846 0.000 -0.486 -0.105 0.048 0.075 -23.504
-0.357 0.498 0.000 -0.143 0.363 0.056 0.060 87.725
1.017 -0.592 -0.002 0.042 -0.531 -0.053 -0.015 0.736
0.275 -0.160 0.282 0.047 0.039 -0.082 -0.029 -0.113
0.275 -0.160 -0.283 0.073 -0.787 -0.001 -0.006 0.077
Oked that. Got a rate message: Time -3, Rate 5.67608, Enter the new common rate
14.000. Did nothing except Oked it.Checked and 14.000 is the rate.
When tried to load into model got warning on wire12. bit controller has
illegal entries. max abs val must be < 2.5.
*We need a better message on the scale factor window*.
Went back. Called algorithm again. Entered 5. in place of 14. Did a build all.
No error messages. Load.
Forgot to do coldstart.

1 Pla Disrupts at .5s. EF2 railed. Probably too much early gas.

Lowered early nl04 demand, and nl04 to 1.e20.
2 Pla Survived but it became clear that EF2L was saturating at 3.1kA.
Engineering owned up to having the limit set wrong. Put it right.

Turn on STRkpsi P=2, I=1, (10/s, 50/s^2). Otherwise the same.
3 Pla Looks fine. We have a strkpsi sweep. RXL is mostly being swept.
ZXL not changing much.

Lowered nl04 to .6 for probe 'calibration'.
Lowered RXL gain to 2.5 (30/s) throughout.
Compressed the strkpsi sweep time to .65-.95. Gain to 4. (20/s)
4 Pla We are not quite getting to where we want.

Strkpsi peak increased to .004 and kinked, P=6(30/s) I=2 (100/s^2).
5 Pla Monster injection at .87 sec.

Insert a +-1cm ZXL ramp to match the strkpsi ramp.
6 Pla No bad injections.

Removed most of the kink because of nearly hitting inner nose at .65s.
Also increased peak of strkpsi sweep to .006.
7 Pla Slight lurch at 1s. Otherwise nice.

No changes for scanning probe.
8 Pla Ok. Some Mo influx during the sweep.

Raise nl04 to 1e20. Move the entire strkpsi sweep up 3mm to make it
more flat-plate.
9 Pla Mo injection at .61s.

Leave the strikpsi sweep peak alone, but lower its pedestal so we
start further in. (-4mm) and end also 1mm in.
10 Pla Fine. No significant Mo injections. Slight OH2 voltage limiting
problem. This is (past) the limit of sweep rate the PS can do.

nl04 to 1.4e20
11 Pla Light in top of machine at the end. No disruption.

nl04 to 1.8e20.
12 Pla Some trouble reaching the density requested.

Tweaked a bit more gas at 20ms to help the early Mo.
B-side upper purged and turned on.
Programmed a 90V pulse from about .48 to .55s.
13 Pla Slightly more density. Still a very fast current rise.

B-side puff to .45s-.6s. nl04 to 2.2, and start its ramp earlier.
Added still more early gas.
14 Pla Disrupt at .8s (strike) appears to be due to OH2L voltage limits.

Changed the sweep to slow the out-ramp. Peak to .9s end to 1.05s.
Increased early gas some more. raised nl04 at .45s.
15 Pla Disruption "Out". Slow current rise, probably due to previous
disruption. Also a Mo injection at .42s takes a bite out of current.
OH2L voltage saturates at about .8s causing an excessive
clearin and big vertical disruption. Oh2L seems to be capable of
about 65V at the end of the shot. About 20V is coming from the
strkpsi ramp, by comparison with prior to the ramp.

Responding to the "OUT" to make the plasma safe.
Remove the strpksi ramp.
Remove the zxl ramp
Switch of b-side.
Lower nl04 to 1.e20.
16 Pla A fine shot but slow current rise (300kA at .1s). OH2L at 45V max.

Put back the strkpsi ramp from .35 s (-.005) to .85s (0mm).
But removed I gain from that wire.
17 Pla OK Mo injection at .74s. OH2L at about 50V.

strkpsi max to .004.
18 Pla OH2L 53V. Fast current ramp back (420kA)
For some reason. OH2U has only more like 27V. These are read from
the compare_volts scope. The bus voltages are not so imbalanced.

Raise nl04 to 1.5e20.
19 Pla OH2L to about 60V.

20 Pla Repeat for the probe

Raise nl04 to 1.7e20
21 Pla OH2L 66V max.

Enable B-side upper. 9V from .5 to .6s.
22 Pla OH2L 66V. Small sign of saturation.

Drop clearin by .004 to .001 to see what it does to OH2V.
23 Pla OH2L 66V. No help from clearin.

Put clearin back.
ZCUR to -1cm from -1.5
24 Pla OH2L 64V. I think it helped.

zcur to -.5cm.
25 Pla OH2L 61V. Yes this really helps.

zcur to 0.
26 Pla 53kA Bounce.

27 Pla OH2L 60V. Injection at .7s.

Strkspi peak lowered to 5mm. And delayed the seep start till .5s.
nl04 to 1.9e20.
28 Pla Fine. OH2L 60V.

Repeat with a slight zxu tweak up to .05m.
29 Pla 60V.

nl04 2.2, widened the b-side gas puff.
30 Pla OH2L 60V.

31 Pla Disrupt at .58s. Density feedback went bad and turned the
gas on full.

Lowered the density back to 2.2.
Made the reverse sweep a little further.
32 Pla Slow current rise.
Numerous Mo injections, very bad one at .25s but survived.

Try again for nl04=2.5
33 Pla Got nl04=2.5. OH2L got 70V. EF1L saturates at 260V.
This illustrates the existing limits.

Session Leader Comments
May 3 1995 08:53:01:660AMBruce LipschultzRun 950503

Engineering operator: F. Silva
Physics operator: I. Hutchinson
Session leader: BLip

Mini proposal # 80: Effect of Separatrix strike point location on divertor
detachment. We will form flat-plate plasmas
where the separatrix strike poinst are above the inner and outer divertor
noses. Using this basic divertor geometry we will explore the scaling of
divertor parameters with density for comparison to the standard vertical plate
divertor. In particular we want to investigate the detachment threshold
dependence on geometry.
Initially we will start out at low density (constant during the shot)
and set up the sweep. Then, once the equilibrium characteristics are settled
we will increase the density from shot to shot. Two shots (at a minimum) will
be required at each density for the scanning probe.

May 3 1995 08:54:20:590AM950503001Bruce Lipschultzshot 1: disrupted midway through shot

May 3 1995 08:56:06:220AM950503002Bruce Lipschultzshot 2: This one made it all the way through. We still do not have STRKPSI
control but the separatrix is near probe 8. nl04=1.e20 during flattop.

May 3 1995 09:00:54:110AM950503002Bruce Lipschultzshot 2: This one made it all the way through. We still do not have STRKPSI
control but the separatrix is near probe 8. nl04=1.e20 during flattop.

May 3 1995 09:18:19:940AM950503003Bruce Lipschultzshot 3: Sweep initiated, more work to be done in this area but good start.
nl04=1.0e20. no FSP scan yet.

May 3 1995 09:29:39:250AM950503004Bruce Lipschultzshot 4: We have shortened up the period of the sweep. It starts at .65
seconds and ends at .95 seconds. The 'peak' is at .8 seconds.
nl04=0.6 e20. Sweep is not far enough. Next several shots will be
spent optimizing sweep before increasing density.

May 3 1995 09:53:37:300AM950503005Bruce Lipschultzshot 5: Big injection at .87 seconds. The sweep carries probe 8 into the
private flux region this shot. Sweep looks good as far as ther divertor
plate is concerned. We are going to try to modify the x-point sweep
slightly so that the separatrix position in front of the probe doesn't
move so far. nl04=0.6e20.

May 3 1995 10:09:27:380AM950503006Bruce Lipschultzshot 6: Added ZXL sweep such that FSP scanning location is fairly
constant. Probe 9 has returned to service for now and we are extending
the 'peak' in the sweep at .8 seconds to make use of it.

May 3 1995 10:22:51:540AM950503007Bruce Lipschultzshot 7: The sweep seems pretty well set. By the way, in sweeping the
strike point up and down the plate RXL sweeps by almost 6 cm and ZXL by
3 cm. Next shot we will try for FSP scan.

May 3 1995 10:40:56:930AM950503007Bruce Lipschultzshot 7: The sweep seems pretty well set. By the way, in sweeping the
strike point up and down the plate RXL sweeps by almost 6 cm and ZXL by
3 cm. Next shot we will try for FSP scan.

May 3 1995 10:42:43:260AM950503008Bruce Lipschultzshot 8: FSP scan just fine. We have decided to move the whole sweep farther
up the plate for the next shot.

May 3 1995 11:00:59:830AM950503009Bruce Lipschultzshot 9: We have just noticed that when the sweep reaches above the nose
that the Mo Monitor registers an increase in Mo in the main plasma. This
was true last shot but doesn't to be true this shot.
Big injection at .6 seconds. no probe scan. nl04=1.e20.

May 3 1995 11:18:26:730AM950503010Bruce Lipschultzshot 10: nl04=1.e20. Probe 9 worked this shot! Sweep went well and we
got a FSP scan.

May 3 1995 11:31:07:580AM950503011Bruce Lipschultzshot 11: FSP scan ok. nl04=1.4e20 (with variations as the strike point sweeps).
probe 9 not alive for this shot.

May 3 1995 11:48:59:620AM950503012Bruce Lipschultzshot 12: density did not quite make it to the desired value of
nl04=1.8e20. It ramps from 1.5 - 1.8 during the strike point sweep.
Probe scan marginal. We will repeat this shot with more gas.

May 3 1995 12:19:48:160PM950503014Bruce Lipschultzshot 14: disruption at .81 seconds with density at nl04=2.e20. Power
supply problem associated with fast sweep of the strike point. First
FSP scan at .625 seconds went but the second at .825 seconds did not.
Probe 9 worked for this shot.

May 3 1995 01:24:00:430PM950503016Bruce Lipschultzshot 16: no sweep, strike point on probe 5 or so. nl04=1.4e20.

May 3 1995 01:30:34:950PM950503017Bruce Lipschultzshot 17: some sweep back. Barely reaches probe 8. No FSP scan.
nl04=1.4e20.

May 3 1995 02:13:56:800PM950503018Bruce Lipschultzshot 18: sweep increased. nl04=1.0e20. no FSP

May 3 1995 02:15:11:510PM950503018Bruce Lipschultzshot 19: nl04= 1.5e20, no FSP scan. Things are still of with power supplies.

May 3 1995 02:25:22:590PM950503020Bruce Lipschultzshot 20: nl04=1.7e20, fsp scan ok, sweep ok. Still looks attached.

May 3 1995 02:39:05:040PM950503020Bruce Lipschultzshot 21: nl04=1.7e20. Still attached. FSP scan and probe 9 working.

May 3 1995 02:45:10:200PM950503022Bruce Lipschultzshot 22: nl04=1.75e20. FSP scan of and Probe 9 ok.

May 3 1995 03:11:19:420PM950503023Bruce Lipschultzshot 23: some evidence of detachment just outside the separatrix on this
shot. Probe 9 data, mo fsp.

May 3 1995 03:24:26:000PM950503024Bruce Lipschultzshot 24: The plasma center is shifted up to -1.0 cm. This seems to
improve the power supply situation. no fsp scan, probe 9 working. There
may be some small amount of detachment (extent 1 mm) shown on probe 8
at these densities (nl04=1.7e20).

May 3 1995 03:47:58:530PM950503025Bruce Lipschultzshot 25: Plasma center up another 0.5 cm with positive results. no
FSP scan and probe 9 ok. detachment possibly in region of separatrix.

May 3 1995 03:50:22:210PM950503026Bruce Lipschultzshot 26: fizzle

May 3 1995 03:52:27:670PM950503027Bruce Lipschultzshot 27: plsma vertically centered, FSP scan and probe 9 ok. Again,
possible detachment showing on probe 8 in region of separatrix.

May 3 1995 04:39:07:020PM950503029Bruce Lipschultzshot 29: fsp scan at nl04=2.e20. probe 9 ok. Still appears that there
is no detachment

May 3 1995 05:02:17:970PM950503030Bruce Lipschultzshot 30: disruption at .6 seconds due to density feedback problem.

May 3 1995 05:05:30:370PM950503031Bruce Lipschultzshot 31: disruption due to density feedback failure.

May 3 1995 05:19:06:460PM950503032Bruce Lipschultzshot 32: nl04=2.1e20, just barely made it after the previous shot's disruption.
fsp scan ok and probe 9 ok.

May 3 1995 06:17:57:880PM950503033Bruce Lipschultzshot 33: nl04 ramping from 2 to 2.6e20 during strike point sweep. fsp
scan and probe 9 ok. There does seem to be detachment on this shot,
again the region of 2 mm outside the separatrix (perhaps further out
as well). One must note that over the period between the the strike
point moving from probe 8 to probe 9 the density rises by a significant
amount ( 2-2.6e20). This might explain the difference in detachment
measured by probes 8 & 9.

May 3 1995 06:21:20:070PM950503033Bruce Lipschultzshot 33: nl04 ramping from 2 to 2.6e20 during strike point sweep. fsp
scan and probe 9 ok. There does seem to be detachment on this shot,
again the region of 2 mm outside the separatrix (perhaps further out
as well). One must note that over the period between the the strike
point moving from probe 8 to probe 9 the density rises by a significant
amount ( 2-2.6e20). This might explain the difference in detachment
measured by probes 8 & 9.

Physics Operator Comments

Engineering Operator Comments
ShotTimeTypeStatusComment
108:29:20:410AMPlasmaOk
208:43:35:170AMPlasmaOk
308:59:48:860AMPlasmaOk
409:19:52:570AMPlasmaOk
509:37:14:310AMPlasmaOk
609:52:34:640AMPlasmaOk
710:10:59:600AMPlasmaOk
810:25:22:120AMPlasmaOk
910:38:20:480AMPlasmaOk
1011:00:07:080AMPlasmaOkNo Faults.
1111:15:25:980AMPlasmaOk
1211:28:15:290AMPlasmaOk
1311:47:33:100AMPlasmaOk
1412:01:31:370PMPlasmaOk
1512:20:29:620PMPlasmaOk
1612:59:32:400PMPlasmaOkNo Faults.
1701:13:47:710PMPlasmaOkNo Faults.
1801:28:46:850PMPlasmaOkNo Faults
1901:52:03:250PMPlasmaOkNo Faults.
2002:07:10:120PMPlasmaOkNo Faults.
2102:18:24:030PMPlasmaOk
2202:32:07:640PMPlasmaOkNo Faults.
2302:46:50:700PMPlasmaOkNo Faults.
2403:01:45:790PMPlasmaOkNo Faults.
2503:15:44:800PMPlasmaOkNo Faults.
2603:26:42:580PMPlasmaOkNo Faults.
2703:36:39:960PMPlasmaOkNo Faults.
2803:54:32:290PMPlasmaOkNo Faults.
2904:06:19:930PMPlasmaOkNo Faults.
3004:22:23:750PMPlasmaOkno faults
3104:36:52:280PMPlasmaOkNo Faults.
3204:51:29:420PMPlasmaOkNo Faults.
3305:05:30:660PMPlasmaOkNo Faults.