Alcator C-Mod Run 1020830 Information

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Miniproposals
Miniproposal:309
Date Filed: 6/21/2002
Title:5.4 T ITB Thermal Transport Investigation
First Author:Alan Lynn
Session Leader:Steve Wukitch (shots 19-31)
Miniproposal:310
Date Filed: 6/21/2002
Title:Te Thermal Transport with Perturbative Techniques
First Author:Alan Lynn
Session Leader:Alan Lynn (shots 1-18)

Operators
Session leader(s):Alan Lynn,Steve Wukitch
Physics operator(s):Joseph Snipes
Engineering operator(s):Bill Cochran,Gary Dekow

Engineering Operator Run Comment
Boronization Recovery/MP310/MP309; SL: Lynn; PO: Snipes; EO:Dekow/Cochra

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:30:210PM
Author: To Be Determined
Run Summary for 1020830 (MP 310)

The first 18 shots were devoted to MP 310. This was an ohmic MP with Bt wiggles and a density scan. The goal
was to vary collisionality to change Te/Ti coupling, then examine the resulting transport using sawtooth heat pulse propagation.
The small (~0.08 T change over 30ms) Bt wiggles were to measure grad Te using the small change in position of the heterodyne
ECE channels. This MP was successfully compleated. The Bt ramps worked well and the sawtooth data looks good.

After shot 18, RF took over to do conditioning for the remainder of the run.
No progress was made on the other MP (#309 - 5.4T ITB's).

Shots 4, 5, 6, 11, 12, 13, 14, and 15 were all usable for the MP. The line averaged densities ranged from ~1.5x10^20 m^3 to ~3.9x10^19 m^3.

The lower density shots had strange looking sawteeth at times, but should be usable.


Shot list:

----------------------------------------------------------------------------
1020830001 lynn SESSION_LEADER Aug 30 2002 9:08:47:986AM
. . . . . . . . . . . . . . . . . . . .
fizzle.
----------------------------------------------------------------------------
1020830002 lynn SESSION_LEADER Aug 30 2002 9:18:47:203AM
. . . . . . . . . . . . . . . . . . . .
dud.
----------------------------------------------------------------------------
1020830003 lynn SESSION_LEADER Aug 30 2002 9:31:01:993AM
. . . . . . . . . . . . . . . . . . . .
dud.
----------------------------------------------------------------------------
1020830004 lynn SESSION_LEADER Aug 30 2002 10:40:23:500AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Bt ramps and sawteeth look good. nl_04 during ramps ~5.6x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
----------------------------------------------------------------------------
1020830005 lynn SESSION_LEADER Aug 30 2002 10:40:39:373AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Bt ramps and sawteeth look good. nl_04 during ramps ~4.4x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
----------------------------------------------------------------------------
1020830006 lynn SESSION_LEADER Aug 30 2002 10:56:23:400AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Bt ramps and sawteeth still look good. nl_04 during ramps ~2.8x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
----------------------------------------------------------------------------
1020830007 lynn SESSION_LEADER Aug 30 2002 11:01:02:016AM
. . . . . . . . . . . . . . . . . . . .
No power shot.
----------------------------------------------------------------------------
1020830008 lynn SESSION_LEADER Aug 30 2002 11:05:38:820AM
. . . . . . . . . . . . . . . . . . . .
fizzle.
----------------------------------------------------------------------------
1020830009 lynn SESSION_LEADER Aug 30 2002 11:33:19:613AM
. . . . . . . . . . . . . . . . . . . .
Plasma. Lots of hard x-rays. nl_04 during ramps ~1x10^19

Bt ramps look fine, but sawteeth (if thats what they are) look funny. Probably not useable for heat pulse propagation.

next shot: push density a bit higher (try for nl_04 ~ 2.2)
----------------------------------------------------------------------------
1020830010 lynn SESSION_LEADER Aug 30 2002 11:50:52:030AM
. . . . . . . . . . . . . . . . . . . .
No power shot.
----------------------------------------------------------------------------
1020830011 lynn SESSION_LEADER Aug 30 2002 12:20:10:243PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Bt ramps look good, nice clear sawteeth, nl_04 during ramps ~ 2.1x10^19. Fantastic.

next shot: repeat
----------------------------------------------------------------------------
1020830012 lynn SESSION_LEADER Aug 30 2002 12:35:09:750PM
. . . . . . . . . . . . . . . . . . . .
Plasma.

There is a change in the sawtooth character at about the same time as the first Bt ramp at 1s (also occured on shot 11).
We'll repeat this shot with the ramps moved to start at t= 0.7 s and see if the change in sawtooth behavior still occurs when thr ramps occur.
----------------------------------------------------------------------------
1020830013 lynn SESSION_LEADER Aug 30 2002 12:47:41:410PM
. . . . . . . . . . . . . . . . . . . .
Plasma.

The sawteeth behavior didn't change with the ramps this time, so that strange behavior does not appear to be correlated
eith the Bt ramps.

next shot: go back and repeat density from shot 6, keep ramps starting at t=0.7s.
----------------------------------------------------------------------------
1020830014 lynn SESSION_LEADER Aug 30 2002 1:03:37:670PM
. . . . . . . . . . . . . . . . . . . .
Plasma. nl_04 ~ 3.8x10^19. A bit higher then we wanted.

next shot: go back try for slightly lower density
----------------------------------------------------------------------------
1020830015 lynn SESSION_LEADER Aug 30 2002 1:17:03:563PM
. . . . . . . . . . . . . . . . . . . .
Plasma. Lost density feedback. Looks like it higher than we wanted.

next shot: try again to repeat shot 6.
----------------------------------------------------------------------------
1020830016 lynn SESSION_LEADER Aug 30 2002 1:20:19:273PM
. . . . . . . . . . . . . . . . . . . .
Dud.
----------------------------------------------------------------------------
1020830017 lynn SESSION_LEADER Aug 30 2002 1:32:33:743PM
. . . . . . . . . . . . . . . . . . . .
No power shot.
----------------------------------------------------------------------------
1020830018 lynn SESSION_LEADER Aug 30 2002 1:46:59:186PM
. . . . . . . . . . . . . . . . . . . .
Dud.

next shot: hand off to RF for RF conditioning.
----------------------------------------------------------------------------



Physics Operator Summaries
Entered: Jul 7 2004 04:37:16:003PM
Author: To Be Determined
Engineering Setup for Friday, August 30,2002

MP 310 Te Thermal Transport with Perturbative Techniques
MP 309 (Provisional) 5.4 T ITB Thermal Transport Investigation

SL: Lynn
PO: Snipes

Overnight ECDC in deuterium stopping at 6:00 am

Run Begins at 09:00 and ends at 17:00
Power systems setup the same as for Shot 1020814007
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, assuming no vacuum problems:

ECE, VUV, DNB

RF Setup: Transmitters 1,2,3,4 in Run On by 07:00

RUN PLAN:

For MP 310, the shots will be without RF. We anticipate about 8-10 shots,
corresponding to two shots at each of four densities (0.3, 0.5, 0.7, 2.0x10^20)
During these shots BT will be varied by ~0.07 T over 40 ms at three times,
1., 1.08 and 1.16 s (similar to shot 1020820024). The field perturbation will
be from the nominal value of 5.4 T and the current will be 800 kA.

Then, we will do some RF conditioning to prepare for MP 309.

For MP 309 we will attempt to form density ITB's with the RF first from J-port
only as in 1010801025 and then if successful with D&E on axis to arrest the
density rise. Then, we'll again insert small field ramps into an ITB
discharge at various times, e.g., 0.5, 1., 1.1 and 1.2 s. Again, the nominal
field wil be 5.4 T and the current will be 800 kA.

Summary: There were a number of problems today that cost the program
considerably. There were three no-power shots due to engineering problems.
Shots 7 and 10 failed to charge the EF1L capacitor banks. No clear cause was
found. Then, shot 17 had a spurious I^2t fault. In addition, there were 5
duds apparently due to unloaded walls since ECDC led to plasmas. There were
also 6 fizzles. There was also one disruption at 0.58 s due to physop error.
Despite all of these problem, MP310 was completed with good data. More RF
conditioning is required to complete MP309. So, the totals were:
16 plasmas (1 disruption)
6 fizzles
5 duds
3 no-power shots
_________
31 pulses


Shot 1: Copied shot 1020820024 and modified TF current waveform to have three
wiggles in it at 1, 1.08, and 1.16 s as requested. Also took 2 ms off
of the prepuff to make it 25 ms duration. Dud!
Shot 2: Increased prepuff by 4 ms to 29 ms duration. Another dud!
Shot 3: Ian suggested raising the first point on RCUR by 0.5 cm to decrease
the rate of rise of Bz at breakdown. Also increased the prepuff by
another 3 ms to 33 ms duration. Another dud! Try ECDC for 30 min
after this shot.
Shot 4: After 30 min ECDC, try again. This time, I corrected the density
feedback so that it has the normal proportional gain and programmed
nl04 in segment 2 to be 1.6 x 10^19 m^-2, which should correspond to
3 x 10^19 m^-3. Early in the shot I programmed nl04 to 3 x 10^19 m^-2
to try to avoid runaways. Also lowered the prepuff to 28 ms
duration. Good shot.
Shot 5: Repeat to try to unload the walls and reduce the density further.
Good shot. Density came down by nearly 20%.
Shot 6: DNB on at 0.5 sec for 0.05 s. Increased prepuff by 2 ms to 30 ms
duration. Good shot! Density somewhat lower.
Shot 7: Increased prepuff by 4 ms to 34 ms duration. Reduced nl04 feedback
request to 2 x 10^19 at segment switch. EF1L commutation bank failed
to charge, so we ran a no-power pulse.
Shot 8: Try again. Fizzle! It appears that there was more gas than we
at breakdown for some reason - perhaps due to the DNB.
Shot 9: Try again. Good shot but with hard x rays. Reached the requested
nl04 of 1.6 x 10^19 m^-2, but sawteeth are not usable.
Shot 10: Increase nl04 to 2.3 x 10^19 m^-2 with a bit more in the current rise
to try to avoid the hard x rays and get a decent low density shot.
EF1L cap bank failed to charge in init again. No power shot.
Shot 11: Try again. Good shot. Got the density we wanted.
Shot 12: Repeat. Good shot.
Shot 13: Moved TF wiggles 0.3 s earlier to start at 0.7 s because there was
a change in the sawtooth character at 1 s just as the wiggles started
on shots 11 and 12. Good shot. Lost TCI density feedback at 0.5 s
which shut off the gas. The sawteeth stayed large during the TF
wiggles.
Shot 14: Raised nl04 up to 2.84 x 10^19 m^-2 to repeat shot 6. Good shot.
Shot 15: Programmed nl04 = 2.5 x 10^19 m^-2 to try to get back to the density
of shot 6. Lost density feedback and got much higher density than
requested, but otherwise it was a good shot.
Shot 16: Try again to repeat the lowish density of shot 6. Dud!
Shot 17: Increased prepuff by 3 ms to 37 ms duration. I^2t fault in init.
No power shot.
Shot 18: One more time . . . Another dud! ECDC for 10 minutes.
Shot 19: Go to higher density. Set nl04 = 8 x 10^19 m^-2. Reduced prepuff
to 27 ms duration. Good shot. Got 2 MW of ICRF with spikes and an
H-mode from 1 to 1.5 s.
Shot 20: Repeat removing the TF wiggles. Good shot.
Shot 21: Fizzle!
Shot 22: Try reducing the prepuff to 24 ms duration. Increased outer gap
by reducing RCUR by 6.5 mm. Good shot!
Shot 23: No, Wukitch asked for a 2.5 cm inner gap. So, I put the RCUR back
where it was on shot 20 and then added 5 mm to CLEARIN. Good shot,
but the inner gap did not change enough to suit Wukitch.
Shot 24: Increase CLEARIN by another 5 mm. Still not enough inner gap.
Decent shot, but only a short weak H-mode.
Shot 25: Increase CLEARIN by another 3 mm and decrease RCUR by 4 mm to
compensate for the change in cLEARIN on the outer gap. Disrupted at
0.58 s. I changed RCUR in the wrong direction and caused the plasma
to become vertically unstable.
Shot 26: Increase RCUR by 8 mm to do the proper compensation for the previous
change in CLEARIN. RCUR now at 0.6615 m for CLEARIN of 1.3 cm.
Fizzle!
Shot 27: Fizzle!
Shot 28: Try again with no changes. Another fizzle!
Shot 29: Try reducing EF4 current by 20 A to -1335 A and decreasing the prepuff
by 2 ms to 22 ms duration. Good shot.
Shot 30: Repeat. Fizzle!
Shot 31: EF4 back up to -1315 A. Good shot.


Session Leader Comments
Aug 30 2002 09:08:47:987AM1020830001Alan Lynnfizzle.
Aug 30 2002 09:18:47:203AM1020830002Alan Lynndud.
Aug 30 2002 09:31:01:993AM1020830003Alan Lynndud.
Aug 30 2002 10:40:23:500AM1020830004Alan LynnPlasma. Bt ramps and sawteeth look good. nl_04 during ramps ~5.6x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
Aug 30 2002 10:40:39:373AM1020830005Alan LynnPlasma. Bt ramps and sawteeth look good. nl_04 during ramps ~4.4x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
Aug 30 2002 10:56:23:400AM1020830006Alan LynnPlasma. Bt ramps and sawteeth still look good. nl_04 during ramps ~2.8x10^19

Bt ramps: deltaB= ~0.08 T at t=1s over ~30 ms.
deltaB= ~0.08 T at t=1.08s over ~30 ms.
deltaB= ~0.08 T at t= 1.16s over ~30 ms.
Aug 30 2002 11:01:02:017AM1020830007Alan LynnNo power shot.
Aug 30 2002 11:05:38:820AM1020830008Alan Lynnfizzle.
Aug 30 2002 11:33:19:613AM1020830009Alan LynnPlasma. Lots of hard x-rays. nl_04 during ramps ~1x10^19

Bt ramps look fine, but sawteeth (if thats what they are) look funny. Probably not useable for heat pulse propagation.

next shot: push density a bit higher (try for nl_04 ~ 2.2)
Aug 30 2002 11:50:52:030AM1020830010Alan LynnNo power shot.
Aug 30 2002 12:20:10:243PM1020830011Alan LynnPlasma. Bt ramps look good, nice clear sawteeth, nl_04 during ramps ~ 2.1x10^19. Fantastic.

next shot: repeat
Aug 30 2002 12:35:09:750PM1020830012Alan LynnPlasma.

There is a change in the sawtooth character at about the same time as the first Bt ramp at 1s (also occured on shot 11).
We'll repeat this shot with the ramps moved to start at t= 0.7 s and see if the change in sawtooth behavior still occurs when thr ramps occur.
Aug 30 2002 12:47:41:410PM1020830013Alan LynnPlasma.

The sawteeth behavior didn't change with the ramps this time, so that strange behavior does not appear to be correlated
eith the Bt ramps.

next shot: go back and repeat density from shot 6, keep ramps starting at t=0.7s.
Aug 30 2002 01:03:37:670PM1020830014Alan LynnPlasma. nl_04 ~ 3.8x10^19. A bit higher then we wanted.

next shot: go back try for slightly lower density
Aug 30 2002 01:17:03:563PM1020830015Alan LynnPlasma. Lost density feedback. Looks like it higher than we wanted.

next shot: try again to repeat shot 6.
Aug 30 2002 01:20:19:273PM1020830016Alan LynnDud.
Aug 30 2002 01:32:33:743PM1020830017Alan LynnNo power shot.
Aug 30 2002 01:46:59:187PM1020830018Alan LynnDud.

next shot: hand off to RF for RF conditioning.
Aug 30 2002 03:07:46:437PM1020830019Steve Wukitch019 BT~5.4 T, Ip~0.8 MA, nl04~0.8
D: 1.0 MW [1.0,1.5] sec
E: 1.0 MW
J: 1.6 MW
result: plasma late EDA
D: 1.0 MW faulting
E: 1.0 MW faulting
J: 1.6 MW faulting
Aug 30 2002 02:28:55:160PM1020830020Alan Lynn
Removed TF wiggles at RF request.
Aug 30 2002 03:07:28:203PM1020830020Steve Wukitch020 BT~5.4 T, Ip~0.8 MA, nl04~0.8
D: 1.0 MW [0.6,1.5] sec
E: 1.0 MW
J: 1.6 MW
result: plasma late EDA
D: 1.0 MW faulting
E: 1.0 MW faulting
J: 1.6 MW faulting
Aug 30 2002 03:07:17:110PM1020830021Steve Wukitch021 fizzle
Aug 30 2002 03:06:14:420PM1020830022Steve Wukitch022 BT~5.4 T, Ip~0.8 MA, nl04~0.8
D: 0.6 MW [0.6,1.5] sec
E: 0.6 MW
J: 1.6 MW
result: plasma late EDA - right gap to 2 cm
D: 0.6 MW faulting late
E: 0.6 MW faulting late
J: 1.6 MW 1 fault
Aug 30 2002 03:39:37:753PM1020830024Steve Wukitch024 BT~5.4 T, Ip~0.8 MA, nl04~0.8 - right gap to ~1.2 cm
left gap to 2.5 cm
D: 0.7 MW [0.6,1.5] sec
E: 0.7 MW
J: 2.0 MW
result: plasma
D: 0.7 MW faulting late looks like the DC0 forward came unstuck
there is a sine wave on D power
E: 0.7 MW faulting late
J: 1.8 MW 2 faults
Aug 30 2002 03:40:03:613PM1020830025Steve Wukitch025 early disruption

Physics Operator Comments
Aug 30 2002 09:02:06:960AMJoseph SnipesEngineering Setup for Friday, August 30,2002

MP 310 Te Thermal Transport with Perturbative Techniques
MP 309 (Provisional) 5.4 T ITB Thermal Transport Investigation

SL: Lynn
PO: Snipes

Overnight ECDC in deuterium stopping at 6:00 am

Run Begins at 09:00 and ends at 17:00
Power systems setup the same as for Shot 1020814007
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, assuming no vacuum problems:

ECE, VUV, DNB

RF Setup: Transmitters 1,2,3,4 in Run On by 07:00

RUN PLAN:

For MP 310, the shots will be without RF. We anticipate about 8-10 shots,
corresponding to two shots at each of four densities (0.3, 0.5, 0.7, 2.0x10^20)
During these shots BT will be varied by ~0.07 T over 40 ms at three times,
1., 1.08 and 1.16 s (similar to shot 1020820024). The field perturbation will
be from the nominal value of 5.4 T and the current will be 800 kA.

Then, we will do some RF conditioning to prepare for MP 309.

For MP 309 we will attempt to form density ITB's with the RF first from J-port
only as in 1010801025 and then if successful with D&E on axis to arrest the
density rise. Then, we'll again insert small field ramps into an ITB
discharge at various times, e.g., 0.5, 1., 1.1 and 1.2 s. Again, the nominal
field wil be 5.4 T and the current will be 800 kA.

Aug 30 2002 09:16:55:173AM1020830001Joseph SnipesShot 1: Copied shot 1020820024 and modified TF current waveform to have three
wiggles in it at 1, 1.08, and 1.16 s as requested. Also took 2 ms off
of the prepuff to make it 25 ms duration. Dud!
Aug 30 2002 09:28:36:760AM1020830002Joseph SnipesShot 2: Increased prepuff by 4 ms to 29 ms duration. Another dud!
Aug 30 2002 10:34:44:913AM1020830003Joseph SnipesShot 3: Ian suggested raising the first point on RCUR by 0.5 cm to decrease the
rate of rise of Bz at breakdown. Also increased the prepuff by another
3 ms to 33 ms duration. Another dud! Try ECDC for 30 min after this
shot.
Aug 30 2002 10:37:15:073AM1020830004Joseph SnipesShot 4: After 30 min ECDC, try again. This time, I corrected the density
feedback so that it has the normal proportional gain and programmed
nl04 in segment 2 to be 1.6 x 10^19 m^-2, which should correspond to
3 x 10^19 m^-3. Early in the shot I programmed nl04 to 3 x 10^19 m^-2
to try to avoid runaways. Also lowered the prepuff to 28 ms duration.
Good shot!
Aug 30 2002 10:37:41:637AM1020830005Joseph SnipesShot 5: Repeat to try to unload the walls and reduce the density further.
Good shot. Density came down by nearly 20%.
Aug 30 2002 10:48:58:793AM1020830006Joseph SnipesShot 6: DNB on at 0.5 sec for 0.05 s. Increased prepuff by 2 ms to 30 ms
duration. Good shot! Density somewhat lower.
Aug 30 2002 10:57:33:730AM1020830007Joseph SnipesShot 7: Increased prepuff by 4 ms to 34 ms duration. Reduced nl04 feedback
request to 2 x 10^19 at segment switch. EF1L commutation bank failed
to charge, so we ran a no-power pulse.
Aug 30 2002 11:21:39:203AM1020830008Joseph SnipesShot 8: Try again. Fizzle! It appears that there was more gas than we
at breakdown for some reason - perhaps due to the DNB.
Aug 30 2002 11:32:32:377AM1020830009Joseph SnipesShot 9: Try again. Good shot but with hard x rays. Reached the requested
nl04 of 1.6 x 10^19 m^-2, but sawteeth are not usable.
Aug 30 2002 11:50:41:780AM1020830010Joseph SnipesShot 10: Increase nl04 to 2.3 x 10^19 m^-2 with a bit more in the current rise
to try to avoid the hard x rays and get a decent low density shot.
EF1L cap bank failed to charge in init again. No power shot.
Aug 30 2002 12:13:43:797PM1020830011Joseph SnipesShot 11: Try again. Good shot. Got the density we wanted.
Aug 30 2002 12:35:22:640PM1020830012Joseph SnipesShot 12: Repeat. Good shot.
Aug 30 2002 12:44:37:843PM1020830013Joseph SnipesShot 13: Moved TF wiggles 0.3 s earlier to start at 0.7 s because there was
a change in the sawtooth character at 1 s just as the wiggles started
on shots 11 and 12. Good shot. Lost TCI density feedback at 0.5 s
which shut off the gas. The sawteeth stayed large during the TF
wiggles.
Aug 30 2002 12:53:20:357PM1020830014Joseph SnipesShot 14: Raised nl04 up to 2.84 x 10^19 m^-2 to repeat shot 6. Good shot.
Aug 30 2002 01:16:36:110PM1020830015Joseph SnipesShot 15: Programmed nl04 = 2.5 x 10^19 m^-2 to try to get back to the density
of shot 6. Lost density feedback and got much higher density than
requested, but otherwise it was a good shot.
Aug 30 2002 01:20:03:053PM1020830016Joseph SnipesShot 16: Try again to repeat the lowish density of shot 6. Dud!
Aug 30 2002 01:39:35:130PM1020830017Joseph SnipesShot 17: Increased prepuff by 3 ms to 37 ms duration. I^2t fault in init.
No power shot.
Aug 30 2002 01:58:13:113PM1020830018Joseph SnipesShot 18: One more time . . . Another dud! ECDC for 10 minutes.
Aug 30 2002 02:18:58:033PM1020830019Joseph SnipesShot 19: Go to higher density. Set nl04 = 8 x 10^19 m^-2. Reduced prepuff
to 27 ms duration. Good shot. Got 2 MW of ICRF with spikes and an
H-mode from 1 to 1.5 s.
Aug 30 2002 02:30:08:410PM1020830020Joseph SnipesShot 20: Repeat removing the TF wiggles. Good shot.
Aug 30 2002 02:50:06:333PM1020830020Joseph SnipesShot 21: Fizzle!
Aug 30 2002 03:05:14:467PM1020830022Joseph SnipesShot 22: Try reducing the prepuff to 24 ms duration. Increased outer gap
by reducing RCUR by 6.5 mm. Good shot!
Aug 30 2002 03:16:20:263PM1020830023Joseph SnipesShot 23: No, Wukitch asked for a 2.5 cm inner gap. So, I put the RCUR back
where it was on shot 20 and then added 5 mm to CLEARIN. Good shot,
but the inner gap did not change enough to suit Wukitch.
Aug 30 2002 03:30:34:723PM1020830024Joseph SnipesShot 24: Increase CLEARIN by another 5 mm. Still not enough inner gap.
Decent shot, but only a short weak H-mode.
Aug 30 2002 03:42:12:553PM1020830025Joseph SnipesShot 25: Increase CLEARIN by another 3 mm and decrease RCUR by 4 mm to
compensate for the change in cLEARIN on the outer gap. Disrupted at
0.58 s. I changed RCUR in the wrong direction and caused the plasma
to become vertically unstable.
Aug 30 2002 03:53:49:743PM1020830026Joseph SnipesShot 26: Increase RCUR by 8 mm to do the proper compensation for the previous
change in CLEARIN. RCUR now at 0.6615 m for CLEARIN of 1.3 cm.
Fizzle!
Aug 30 2002 04:05:36:527PM1020830027Joseph SnipesShot 27: Fizzle!
Aug 30 2002 04:21:16:300PM1020830028Joseph SnipesShot 28: Try again with no changes. Another fizzle!
Aug 30 2002 04:42:54:193PM1020830029Joseph SnipesShot 29: Try reducing EF4 current by 20 A to -1335 A and decreasing the prepuff
by 2 ms to 22 ms duration. Good shot.
Aug 30 2002 04:52:38:363PM1020830030Joseph SnipesShot 30: Repeat. Fizzle!
Aug 30 2002 05:03:04:223PM1020830031Joseph SnipesShot 31: EF4 back up to -1315 A. Good shot.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:00:52:350AMPlasmaOk
209:13:48:017AMPlasmaOk
309:26:31:357AMPlasmaOk
410:14:05:130AMPlasmaOk
510:26:54:307AMPlasmaOk
610:40:11:797AMPlasmaOk
710:53:34:630AMPlasmaBadEF1L Commutation Bank Didn't Charge
811:03:46:817AMPlasmaOk
911:19:22:450AMPlasmaOk
1011:47:38:463AMPlasmaOk
1112:08:25:820PMPlasmaOk
1212:21:11:650PMPlasmaOk
1312:37:08:330PMPlasmaOk
1412:51:05:667PMPlasmaOk
1501:04:27:437PMPlasmaOk
1601:18:02:347PMPlasmaOk
1701:31:16:510PMPlasmaBadI2T Fault by Bad TF Reading
1801:41:13:790PMPlasmaOk
1902:12:58:273PMPlasmaOk
2002:26:17:530PMPlasmaOk
2102:41:21:723PMPlasmaOk
2202:54:24:277PMPlasmaOk
2303:07:29:873PMPlasmaOk
2403:20:53:943PMPlasmaOk
2503:33:42:087PMPlasmaOk
2603:46:52:687PMPlasmaOk
2704:00:08:970PMPlasmaOk
2804:13:02:007PMPlasmaOk
2904:25:47:400PMPlasmaOk
3004:46:26:463PMPlasmaOk
3104:59:19:047PMPlasmaOk