Alcator C-Mod Run 1040427 Information

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Miniproposals
Miniproposal:345
Date Filed: 6/20/2003
Title:Initial Mode Conversion Current Drive Experiments
First Author:Steve Wukitch
Session Leader:Yijun Lin (shots 1-28)

Operators
Session leader(s):Yijun Lin
Physics operator(s):Joseph Snipes
Engineering operator(s): Unknown

Engineering Operator Run Comment
MP# 343A And MP# 345,MC Flow Drive/Current Drive at 8T. Lin/Parisot/Snip

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:05:070PM
Author: Yijun Lin
1040427: MP343A and MP345

Purpose: MP#343A and MP 345, MC flow drive/current drive at 8 T.
SL: Lin/Parisot
PO: Snipes
-------------------
Run Plan:

Start with 1040423002, 5.4 T. After tests load 1040423017, nl04~0.75e20
m^-2 for 8T operation.

1. Scan He3 puff/density until a good MC target is obtained (PCI may
provide a definite answer). Using moderate RF power (<= 3.5 MW).
Ip = 1.2 MA, BT~7.9 T. We will avoid
H-mode. J-port power will be modulated.
2. Repeat the plasma, and scan HIREX viewing location shot by shot
to search rf correlated flow.
3. Change J-antenna phase and monitor current drive. Measurements from MSE
will be important.
4. If time permits, do field/density/current scan for both flow drive and
current drive.

Run summary: (maybe it is the run day with the most 8T plasma shots.)

In most plasma shots, the PCI detected mode converted wave(s). In some
shot, perhaps both MC IBW and MC ICW were observed. The current setup of
PCI does not have enough spatial resolution to resolve IBW.
The observed waves at
k_R at -(3-5) /cm may be an aliased IBW signal at k_R about
2*k_Nyquist -(3-5) ~ 11-13/cm. The other wave observed
had k_R near the Nyquist k about 8/cm, which is believed to be an ICW on the
LFS of the IBW. The mode conversion layer and structure
seen from the PCI was moving in
directions as expected with B field, He3 level, etc. The signal level of
the MC ICW appeared to be affected by the distance of the MC layer to
the magnetic axis (B_pol effect). More analysis is
underway.

By setting the HIREX viewing chords around the mode conversion layer
location, we tried to look for flow driven by the MC waves. While the
RF power is modulated, there is no obvious modulated poloidal flow seen in
HIREX measurement under any conditions we tried. I suspect that the flow, if
any, is below the sensitivity/uncertainty of the HIREX measurement.
More analysis is still underway.

We also ran plasmas with low density and phased antenna for MCCD study.
There were some data from MSE with/without RF. More analysis is
underway.


Physics Operator Summaries
Entered: Jul 7 2004 04:36:50:113PM
Author: Joseph Snipes
Purpose: MP#343A and MP 345, MC flow drive/current drive at 8 T.
SL: Lin/Parisot
PO: Snipes

Overnight ECDC in D2 at 2e-4 Torr

Run begins at 08:00 and ends at 20:00.

Power systems the same as 1040423017 for 8 T plasmas
1040423002 for 5.4 T plasmas

Needs B-side upper with 15 PSI He3.
Needs A-coils

Diagnostics:
GPC2 set for 8 T, TCI, FRECE (5.4 T discharge)
McPherson/Chromex to monitor He3
PCI for MC waves
MSE from DNB for current profile
HIREX and HIREX jr for flow
----------------------------------------------------------------------------
RF Setup: All four transmitters in RUN-ON by 07:00 AM
----------------------------------------------------------------------------
Run Plan:

Start with 1040423002, 5.4 T. After tests load 1040423017, nl04~0.75e20
m^-2 for 8T operation.

1. Scan He3 puff/density until a good MC target is obtained (PCI may
provide a definite answer). Using moderate RF power (<= 3.5 MW).
Ip = 1.2 MA, BT~7.9 T. J-port power will be modulated.
2. Repeat the plasma, and scan HIREX viewing location shot by shot
to search rf correlated flow. 3. Change J-antenna phase and monitor current drive. Measurements from MSE
will be important. 4. If time permits, do field/density/current scan for both flow drive and
current drive.

Summary: The machine ran rather well with only a few minor delays given that there were at least
20 minutes or more between shots for cooling at 8 T. There were 28 shots, one TF test, one shot
with no EF4 because of operator error, and one fizzle. There were then 25 plasmas, 4 of
which disrupted. Two disruptions were due to density feedback failure.
The other two disruptions were apparently induced by impurity injection during the RF, though it
is not clear if the RF generated the impurities. The others ramped down nicely. Mode conversion
was observed though the flow drive was not. See the session leader's summary for more details.

Shot 1: TF test with EF1.
Shot 2: Copied shot 1040423002 at 5.4 T, 1 MA. Good shot.
Shot 3: Copied shot 1040423017. He3 puff from 0.3 to 0.468 s on Pulse Gas 2 as in the copied shot. TF current
set to 219 kA. Good shot.
Shot 4: Increased Ar puff from 40 to 60 ms duration. Good shot.
Shot 5: Increased Ar puff from 60 to 80 ms duration. Disrupted at 1.39 s. Density feedback failed at the
start of the pulse so gas was full on.
Shot 6: Increased Ar puff from 80 to 100 ms duration. Good shot.
Shot 7: Decreased TF current to 213.7 kA to go to 7.7 T. Good shot.
Shot 8: Increased TF current to 223.4 kA to go to 8.05 T. Good shot.
Shot 9: Decreased TF current back to 219 kA. Decreased He3 puff to 100 ms duration. Good shot.
Shot 10: Decreased He3 puff to 50 ms duration. Good shot.
Shot 11: Increased He3 puff to 200 ms duration. No EF4. No plasma.
Shot 12: Repeat with EF4. Good shot.
Shot 13: Repeat. Good shot.
Shot 14: Repeat. Good shot.
Shot 15: Repeat. Good shot.
Shot 16: Repeat. Disrupted at 1.19 s.
Shot 17: Reduced He3 puff to 180 ms duration. Good shot.
Shot 18: Repeat. Good shot.
Shot 19: Repeat. Disrupted at 0.927 s.
Shot 20: Repeat. Fizzle!
Shot 21: Reduced EF4 current by 10 A from -1315 A to -1325 A. Good shot.
Shot 22: Reduced nl04 to 6 x 10^19 m^-2. Reduced He3 puff to 150 ms duration. Good shot.
Shot 23: Repeat. Good shot, but there were lots of runaways early.
Shot 24: Raised Pulse Gas 3 between 0.053 and 0.1 s from 35 V to 100 V to try to eliminate the runaways.
Good shot, but the runaways were not reduced.
Shot 25: Increased prepuff by 2 ms to 21 ms duration to attempt to eliminate the runaways. Good shot. Runaways
were reduced a bit, but are still present.
Shot 26: Increased prepuff by 2 ms to 23 ms duration to attempt to eliminate the runaways. Good shot.
Shot 27: Repeat. Good shot.
Shot 28: Repeat. Disrupted at 1.09 s due to density feedback failure.

Session Leader Comments
Apr 28 2004 09:24:25:380AMYijun Lin
Run summary:

In most plasma shots, the PCI detected mode converted wave(s). In some
shot, perhaps both MC IBW and MC ICW were observed. The current setup of
PCI does not have enough max-k to resolve IBW, and the observed waves at
k_R at -(3-5) /cm may be an aliased IBW signal. The other wave observed
had k_R near the Niquist k about 8/cm, which is believed to be an ICW on the
LFS of the IBW. The mode conversion layer and structure
seen from the PCI was moving in
directions as expected with B field, He3 level, etc. The signal level of
the MC ICW seems also to be affected by the distance of the MC layer to
the magnetic axis (B_pol effect). More analysis is
underway.

By setting the HIREX viewing chords around the mode conversion layer
location, we tried to look for flow driven by the MC waves. While the
RF power is modulated, there is no obvious poloidal flow seen in
HIREX measurement under any conditions we tried. I suspect that the flow, if
any, is below the sensitivity/uncertainty of the HIREX measurement.
More analysis is still underway.

We also ran plasmas with low density and phased antenna for MCCD study.
There were some data from MSE with/without RF. More analysis is
underway.

Apr 27 2004 07:58:40:827AM1040427001Yijun Linshot 01: Power supply test. (50 kA TF test)
Apr 27 2004 08:45:05:963AM1040427003Yijun Linshot 03: Load shot 1040423017.
Bt = 7.9 Telsa, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
D: 0.4 MW, [.6, 1.2] sec.
E: .8 MW [.6,1.2] sec
J: 2.2 MW [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 170 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m
Result: plasma. full length.
Several H-modes.
No signal from HIREX.
PCI saw MC wave in ch 16, 17, 18.
Next: run only J port to avoid H-mode. Same He3. More argon next shot.
Apr 27 2004 09:11:48:743AM1040427004Yijun Linshot 04:
Bt = 7.9 Telsa, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 170 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m
Result: plasma. full length. L-mode
Slight density increase with J-power.
PCI saw MC wave in ch 16, 17, 18.
and also in chan 1-13. Possibly two peaks (IBW/ICW) in k-spectrum.
(suspect the MC layer at PCI ch 14-15 location)
More argon next shot.
Apr 27 2004 09:44:52:593AM1040427005Yijun Linshot 05:
Bt = 7.9 Telsa, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 170 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m
Result: plasma. disruption caused by TCI failure.
Apr 27 2004 10:46:24:953AM1040427007Yijun Linshot 07:
Bt = 7.7 Telsa, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 170 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m

result: plasma, full length. L-mode.

PCI signal peaks at ch 1. Aother peak at ch 14-18.
Near zero at ch 10.
(PCI structure is moving with the B field. Perfect. The mode conversion
is real!)

Next: 8.05 Tesla

Apr 29 2004 02:19:35:530PM1040427008Yijun Linshot 08:
Bt = 8.03 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 170 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m

result: plasma, full length. L-mode.

PCI signal peaks at ch 10 as expected. No 2nd peak seen.
(It is likely that the 2nd peak is ICW peak, which may
become much weak when the MC layer is too close to the axis).
But I need more test.

Possible poloidal flow?

Next: 7.9 T, reduce He3 puff to 100 ms to see whether there is another
peak on the higher field.
Apr 29 2004 02:19:56:953PM1040427009Yijun Linshot 09:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 60 ms on, 60 ms off.
He3 puff 100 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m

Result: plasma, full length. L-mode.

PCI signal still peaks at CH 6, same as shot 6. but the width is
narrower.

Next: modulate RF at 100 ms on, 100 ms off to get better timing
for HIREX. Lower He3 down to 50 ms.
Apr 27 2004 12:14:18:963PM1040427010Yijun Linshot 10:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 100 ms on, 100 ms off.
He3 puff 50 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m

Result: plasma, full length. L-mode.

PCI signal peaks at Ch 9. It moves closer to the axis. No 2nd peak
is distinguishable.

Next: Raise He3 puff to 200 ms.
Apr 27 2004 12:27:05:423PM1040427011Yijun Lin
shot 11: dud. No EF4.
Apr 27 2004 01:23:34:363PM1040427012Yijun Linshot 12:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 100 ms on, 100 ms off.
He3 puff 200 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.66 m

Result: plasma, full length. L-mode.
PCI signal peaks from ch1 - ch10.
No flow in Hirex plus/minus 4 cm vertically

Next: move the HIREX view to plus/minus 2 cm vertically.
Same plasma.
Apr 27 2004 01:23:53:863PM1040427013Yijun Linshot 13:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 100 ms on, 100 ms off.
He3 puff 200 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: plasma, full length. L-mode.
PCI signal peaks from ch2 - ch8.
Still nothing in HIREX. View at plus/minus 3 cm

Next: move the HIREX view to plus/minus 5 cm vertically.
Same plasma.

Apr 27 2004 01:46:18:970PM1040427014Yijun Linshot 14:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 100 ms on, 100 ms off.
He3 puff 200 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: plasma, full length. L-mode.
PCI signal peaks from ch2 - ch8.
Still nothing in HIREX. View at plus/minus 5 cm

Next: move the HIREX view to plus/minus 5 cm vertically.
Same plasma.
PCI very similar to shot 13.
Still no flow. Next view at plus/minus 4 cm.
Apr 27 2004 02:08:35:780PM1040427015Yijun Linshot 15:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase +152, [0, pi, pi, 0]
Modulated. 100 ms on, 100 ms off.
He3 puff 200 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: plasma, full length. L-mode.
PCI signal peaks from ch2 - ch8.
Still nothing in HIREX. View at plus/minus 4 cm

Next: move the HIREX view to plus/minus 5 cm vertically.
Same plasma.
PCI very similar to shot 13.
Still no flow.

Next: phase antenna at digital phase 230.
Apr 27 2004 03:03:52:190PM1040427016Yijun Linshot 16:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 200 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: plasma, disrupted 1.12 sec.
PCI signal peaks from ch1 - ch8.
Still nothing in HIREX. View at plus/minus 4 cm
Next: repeat. He3 puff at 180 ms. tune RF.
Apr 27 2004 03:33:34:480PM1040427017Yijun Linshot 17:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 180 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: Plasma full length. RF tripped.
HIREX #2 HV tripped. Only #4 data. Inconlusive.
PCI saw two peaks, ch1 and ch5. Are there two waves?

Next: repeat to get better HIREX data.

Apr 27 2004 03:56:58:290PM1040427018Yijun Linshot 18:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 180 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: Plasma full length. RF tripped.
Both #2 and #4 data. Inconclusive.

PCI saw two peaks, ch1 and ch5. Are there two waves?

Next: repeat to get better HIREX data. Slightly change RF modulation
timing.
Apr 27 2004 04:27:35:470PM1040427019Yijun Linshot 19:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 180 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: Plasma. Disrupted 0.92 sec.
Both #2 and #4 data. Still no flow.
PCI saw two peaks, ch1 and ch4.

Next: CHange antenna phasing to -pi/2. Digital phase at 50.
Apr 27 2004 04:59:40:960PM1040427020Yijun Linfizzle
Apr 27 2004 05:26:50:113PM1040427021Yijun Linshot 21:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.75 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 50,
[0, -pi/2, -pi, -3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 180 ms.
DNB [0.8-0.85] sec
HIREX at R ~ 0.67 m

Result: Plasma. full length

Next: Lower density. Also to see whether it helps DNB.
Lower He3 to 150 ms.
Apr 27 2004 05:50:39:927PM1040427022Yijun Linshot 22: for MCCD
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 50,
[0, -pi/2, -pi, -3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec, didn't fire
HIREX at R ~ 0.67 m

Result: Plasma. full length
PCI peak ch1-ch8.
HIREX tripped out. No data

Next: repeat.
Apr 27 2004 06:16:23:473PM1040427023Yijun Linshot 23: for MCCD
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 50,
[0, -pi/2, -pi, -3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX at R ~ 0.66 m

Result: Plasma. full length
HIREX tripped out.
PC signal similar to shot 22.
MSE data too noisy.
Apr 27 2004 07:12:19:020PM1040427024Yijun Linshot 24: for MCCD
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 50,
[0, -pi/2, -pi, -3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX at R ~ 0.67 m

Result: Plasma. full length
MSE signals were better.
HIREX tripped out at 0.7 sec. Flow? unclear.
PCI saw two peaks. one at ch9 another at ch 17.


Next: reload shot 23.
Apr 27 2004 07:12:35:617PM1040427025Yijun Linshot 25: for MCCD, reload shot 23
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 50,
[0, -pi/2, -pi, -3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX at R ~ 0.67 m

Result: Plasma. full length
Hirex at +/- 5 cm. No flow.
PCI has two peaks ch6 and ch18 with two different k-numbers.

Next: digital phase 230, same RF. HIREX view +/- 6cm
Apr 27 2004 07:26:03:020PM1040427026Yijun Linshot 26: for MCCD
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX view +/- 6cm

Result: Plasma. full length
Flow? might be.

Next: repeat. But no RF at Beam time.
Apr 27 2004 07:48:40:007PM1040427027Yijun Linshot 27:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX view +/- 6cm

Result: Plasma. full length
Flow? not at all.

Next: repeat shot 26. Hirec view at +/- 3 cm.
Apr 27 2004 08:07:04:600PM1040427028Yijun Linshot 28:
Bt = 7.9 Tesla, Ip = 1.2 MA, nl04 = 0.6 e20m^-2
J: 2.5 MW, [0.6,1.2] sec. Digital phase 230,
[0, pi/2, pi, 3/2pi] phase
Modulated. 100 ms on, 100 ms off.
He3 puff 150 ms.
DNB [1.1-1.15] sec
HIREX view +/- 3cm

Result: Plasma. full length.
Flow, not.

Physics Operator Comments
Apr 27 2004 07:57:16:813AMJoseph SnipesPurpose: MP#343A and MP 345, MC flow drive/current drive at 8 T.
SL: Lin/Parisot
PO: Snipes

Overnight ECDC in D2 at 2e-4 Torr

Run begins at 08:00 and ends at 20:00.

Power systems the same as 1040423017 for 8 T plasmas
1040423002 for 5.4 T plasmas

Needs B-side upper with 15 PSI He3.
Needs A-coils

Diagnostics:
GPC2 set for 8 T, TCI, FRECE (5.4 T discharge)
McPherson/Chromex to monitor He3
PCI for MC waves
MSE from DNB for current profile
HIREX and HIREX jr for flow
----------------------------------------------------------------------------
RF Setup: All four transmitters in RUN-ON by 07:00 AM
----------------------------------------------------------------------------
Run Plan:

Start with 1040423002, 5.4 T. After tests load 1040423017, nl04~0.75e20
m^-2 for 8T operation.

1. Scan He3 puff/density until a good MC target is obtained (PCI may
provide a definite answer). Using moderate RF power (<= 3.5 MW).
Ip = 1.2 MA, BT~7.9 T. J-port power will be modulated.
2. Repeat the plasma, and scan HIREX viewing location shot by shot
to search rf correlated flow. 3. Change J-antenna phase and monitor current drive. Measurements from MSE
will be important. 4. If time permits, do field/density/current scan for both flow drive and
current drive.
Apr 27 2004 07:59:02:467AM1040427001Joseph SnipesShot 1: TF test with EF1.
Apr 27 2004 08:13:48:380AM1040427002Joseph SnipesShot 2: Copied shot 1040423002 at 5.4 T, 1 MA. Good shot.
Apr 27 2004 08:30:58:223AM1040427003Joseph SnipesShot 3: Copied shot 1040423017. He3 puff from 0.3 to 0.468 s on Pulse Gas 2 as in the copied shot. TF current
set to 219 kA. Good shot.
Apr 27 2004 08:58:00:287AM1040427004Joseph SnipesShot 4: Increased Ar puff from 40 to 60 ms duration. Good shot.
Apr 27 2004 09:25:07:203AM1040427005Joseph SnipesShot 5: Increased Ar puff from 60 to 80 ms duration. Disrupted at 1.39 s. Density feedback failed at the
start of the pulse so gas was full on.
Apr 27 2004 10:14:28:650AM1040427006Joseph SnipesShot 6: Increased Ar puff from 80 to 100 ms duration. Good shot.
Apr 27 2004 10:31:43:777AM1040427007Joseph SnipesShot 7: Decreased TF current to 213.7 kA to go to 7.7 T. Good shot.
Apr 27 2004 11:43:08:360AM1040427009Joseph SnipesShot 9: Decreased TF current back to 219 kA. Decreased He3 puff to 100 ms duration. Good shot.
Apr 27 2004 12:04:39:190PM1040427010Joseph SnipesShot 10: Decreased He3 puff to 50 ms duration. Good shot.
Apr 27 2004 12:27:51:953PM1040427011Joseph SnipesShot 11: Increased He3 puff to 200 ms duration. No EF4. No plasma.
Apr 27 2004 12:49:35:937PM1040427012Joseph SnipesShot 12: Repeat with EF4. Good shot.
Apr 27 2004 01:12:00:200PM1040427013Joseph SnipesShot 13: Repeat. Good shot.
Apr 27 2004 01:58:03:103PM1040427014Joseph SnipesShot 14: Repeat. Good shot.
Apr 27 2004 01:58:19:633PM1040427015Joseph SnipesShot 15: Repeat. Good shot.
Apr 27 2004 02:33:10:310PM1040427016Joseph SnipesShot 16: Repeat. Disrupted at 1.19 s. RF phasing was changed for this shot.
Apr 27 2004 03:16:42:963PM1040427017Joseph SnipesShot 17: Reduced He3 puff to 180 ms duration. Good shot.
Apr 27 2004 03:42:07:850PM1040427018Joseph SnipesShot 18: Repeat. Good shot.
Apr 27 2004 04:18:51:620PM1040427019Joseph SnipesShot 19: Repeat. Disrupted at 0.927 s.
Apr 27 2004 04:48:19:550PM1040427020Joseph SnipesShot 20: Repeat. Fizzle!
Apr 27 2004 05:17:54:380PM1040427021Joseph SnipesShot 21: Reduced EF4 current by 10 A from -1315 A to -1325 A. Good shot.
Apr 27 2004 05:45:29:303PM1040427022Joseph SnipesShot 22: Reduced nl04 to 6 x 10^19 m^-2. Reduced He3 puff to 150 ms duration. Good shot.
Apr 27 2004 06:16:18:693PM1040427023Joseph SnipesShot 23: Repeat. Good shot, but there were lots of runaways early.
Apr 27 2004 06:37:21:303PM1040427024Joseph SnipesShot 24: Raised Pulse Gas 3 between 0.053 and 0.1 s from 35 V to 100 V to try to eliminate the runaways.
Good shot, but the runaways were not reduced.
Apr 27 2004 07:05:36:473PM1040427025Joseph SnipesShot 25: Increased prepuff by 2 ms to 21 ms duration to attempt to eliminate the runaways. Good shot. Runaways
were reduced a bit, but are still present.
Apr 27 2004 07:39:52:677PM1040427026Joseph SnipesShot 26: Increased prepuff by 2 ms to 23 ms duration to attempt to eliminate the runaways. Good shot.
Apr 27 2004 07:40:53:850PM1040427027Joseph SnipesShot 27: Repeat. Good shot.
Apr 27 2004 08:05:23:693PM1040427028Joseph SnipesShot 28: Repeat. Disrupted at 1.09 s due to density feedback failure.
Apr 27 2004 08:06:19:270PM1040427028Joseph SnipesSummary: The machine ran rather well with only a few minor delays given that there were at least
20 minutes or more between shots for cooling at 8 T. There were 28 shots, one TF test, one shot
with no EF4 because of operator error, and one fizzle. There were then 25 plasmas, 4 of
which disrupted. Two disruptions were due to density feedback failure.
The other two disruptions were apparently induced by impurity injection during the RF, though it
is not clear if the RF generated the impurities. The others ramped down nicely. Mode conversion
was observed though the flow drive was not. See the session leader's summary for more details.

Engineering Operator Comments
ShotTimeTypeStatusComment
107:57:49:547AMTestOk
208:10:32:973AMPlasmaOk
308:29:02:130AMPlasmaOk
408:54:45:490AMPlasmaOk
509:21:21:580AMPlasmaOk
609:56:32:913AMPlasmaOk
710:29:46:823AMPlasmaOk
811:07:53:263AMPlasmaBadTF IOC Late After 4S
911:37:56:770AMPlasmaOk
1012:00:57:083PMPlasmaOk
1112:24:43:173PMPlasmaBadEF4 Was Not Enabled
1212:47:33:017PMPlasmaOk
1301:10:19:467PMPlasmaOk
1401:33:19:277PMPlasmaOk
1501:56:07:883PMPlasmaOk
1602:19:16:680PMPlasmaBadTF type 1 flt
1703:15:10:463PMPlasmaOk
1803:38:21:540PMPlasmaOk
1904:16:32:090PMPlasmaOk
2004:45:56:833PMPlasmaOk
2105:15:29:863PMPlasmaOk
2205:42:16:660PMPlasmaOk
2306:05:00:693PMPlasmaOk
2406:28:58:820PMPlasmaOk
2506:51:35:100PMPlasmaOk
2607:15:02:723PMPlasmaOk
2707:37:45:007PMPlasmaOk
2808:00:17:380PMPlasmaOk