Alcator C-Mod Run 1001107 Information

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Miniproposals
Miniproposal:236
Date Filed: 3/9/1999
Title:Edge Pedestal Assymetries with Reversed Field
First Author:Robert Granetz
Session Leader:T. Sunn Pederson (shots 1-21)
Session Leader:Robert Granetz (shots 1-21)

Operators
Session leader(s):T. Sunn Pederson,Robert Granetz
Physics operator(s):Robert Granetz
Engineering operator(s):Bill Byford,Bill Parkin

Engineering Operator Run Comment
SL:Granetz/Pederson PO:Granetz EO:Byford/Parkin MP #236 H-Mode pedestal

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:25:383PM
Author: To Be Determined
Physics operator summary for run 1001107:

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: R. Granetz/T. Sunn Pedersen
Physics operator: R. Granetz

Summary: This was not a great day as far as plasma operation goes. Of the
plasmas that we were able to get, all of them disrupted when the
auxiliary power reached 2 MW. No H-modes were observed. The run
was plagued by fizzles early on, but startup reliability improved
after a while. Unfortunately, computer problems
caused major delays in the afternoon. Late in the run we
determined that the disruptions were caused by E-port when
operated at about 1 MW. One positive note is that ECDC in D2
between shots kept the H/D ratio down to 3-4%. This run will be
continued tomorrow.

Scorecard: 8 plasmas
8 fizzles
1 dud (power supply failure)
0 tests
4 aborted and/or screwed up by computers
----------
21 total

-------------------------------------------------------------------------------

Engineering setup and run plan for Tuesday 07 Nov 2000.

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: Granetz/Pedersen
Physics operator: Granetz

ECDC in D2 overnight, ending 2 hours before the run.

Run starts at 09:00 and ends at 17:00.

Power systems as on 1001106024.

Gas setup

fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED


We would like the following gate valves should be enabled:
ECE, VUV, Beast

-------------------------------------------------------------------------------

Run Plan:

Start with 0.8 MA, lower null plasma. We probably need at least 2.5 MW of
ICRF for >200 ms. Ideally we'd like 3+ MW for 0.5 s, but we'll take what
we can get. Assuming we do indeed get H-modes with reversed field, we would
then try it at 1.0 MA, and then at 1.2 MA. Argon puffing will also be
required for JR to get up/down argon profiles.

I'll load segment 1 from 1001106020 (late shot on Monday), and segment 2 from
1001103022 (last plasma on Friday), except I'll set the density to
nl_04=1.0e20 m-2. I've saved this to scratch_disk:[granetz]pcs_1001107000.

-------------------------------------------------------------------------------

Overnight ECDC in D2.

Hybrid coldstart done; no errors found

Loaded shot scratch_disk:[granetz]1001107000 (see preceding note).

-------------------------------------------------------------------------------

ECDC in D2 will be done between shots today.

Shot 01 -- Fizzle. Fields need tweaking.

Next shot: add -15 A to IC_EF4 and -0.5 mT to Br0 offset.

ECDC in D2 is being done between shots.

Shot 02 -- Plasma. Disrupted at t=0.75 s, just as the RF gets up to 2 MW.
It's obviously due to a large impurity injection. Plasma startup
looks good.

Next shot: no PCS changes. (between-shot ECDC is being done)

Shot 03 -- Fizzle. Not surprising after the disruption. Fields look good.

Next shot: no PCS changes. (between-shot ECDC is being done)

Shot 04 -- Fizzle.

Next shot: reduce pre-fill puff by 2 ms (to 20 ms)

Shot 05 -- Fizzle. Gas pressure is still a touch high.

Next shot: reduce pre-fill puff by another 2 ms (to 18 ms)
No ECDC after this shot.

Shot 06 -- Fizzle. Late breakdown...almost went. Gas pressure was a little
too low.

Next shot: raise pre-fill back up to 20 ms.
No ECDC after this shot.

Shot 07 -- Fizzle. Almost made it. Looks like it hit on the outside.

Next shot: raise pre-fill 1 more ms (to 21 ms)
No ECDC after this shot.

Shot 08 -- Dud. No EF2's.

Next shot: no PCS changes.

Shot 09 -- Plasma. 0.8 MA. Disrupted at 0.87 s. Can't see anything obvious
on the videos at the time of the disruption. Prf peaks at 2.0 MW.
H/D=3-4%.

Next shot: no PCS changes. Argon will be enabled.

Shot 10 -- Plasma. Disrupted at t=0.85 s. Prf peaks at 2.0 MW. H/D=4-5%.
Zeff=1.25. No injection observable from antennas, but the
disruptions are definitely due to large injections. Strike points
look fine.

Next shot: reduce TF from 5.37 to 5.20 T to aid H-mode threshold.
ECDC is turned on after this shot.

Shot 11 -- Plasma. Disrupted at t=0.77 s. Prf peaks at 2 MW. Btor=5.24 T.
H/D=4%. Still looks like an injection is killing the plasma.

Next shot: no PCS changes, but turn off the RF for the next shot.

Shot 12 -- Plasma. Good shot. Makes it all the way through rampdown. So it
looks like the disruptions are indeed due to the RF power.
Elongation is increasing late in the shot because of the ZXL
programming. H/D=3%.

Next shot: change ZXL programming to avoid increasing elongation,
turn on J-port transmitter only, with 1 MW of power.
Continue with ECDC between shots.

Shot 13 -- Fizzle. Fields and gas look identical to the previous shot.

Next shot: no changes.

Shot 14 -- Fizzle. Bz might be a touch too negative.

Next shot: raise IC_EF4 by +10 A.

Shot 15 -- Aborted due to computer problems.

Long delay due to computer problems.

Shot 16 -- Plasma. Good shot. J-port gave 1.2 MW. D and E were off.
H/D=3-3.5%, even during the RF pulse. Zeff=1.2. No H-modes.

Next shot: test D, E, and J antennas individually.
ECDC is on between shots.

Shot 17 -- Aborted due to computer problems.

Shot 18 -- Aborted due to computer problems.

Shot 19 -- Aborted due to computer problems. (Actually, at least one PF
supply fired, but we don't know which one(s), because there was
no data acquisition.)

Shot 20 -- Plasma. Disrupted at t=0.62 s, while the E-antenna (only) was
on. I'd say that's pretty conclusive.

Next shot: run D and J together, and keep E off.

Shot 21 -- Plasma. Good shot. J had many faults. D worked very well at
1.07 MW. E also worked well at 0.5 MW by itself (after D and J
turned off). No H-modes. Total power did not stay above 1.07 MW
for more than a few milliseconds at a time.

End of run. (To be continued tomorrow)

Physics Operator Summaries
Entered: Jul 7 2004 04:37:12:630PM
Author: To Be Determined
Physics operator summary for run 1001107:

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: R. Granetz/T. Sunn Pedersen
Physics operator: R. Granetz

Summary: This was not a great day as far as plasma operation goes. Of the
plasmas that we were able to get, all of them disrupted when the
auxiliary power reached 2 MW. No H-modes were observed. The run
was plagued with unreliable startups, but computer problems also
caused major delays in the afternoon. Late in the run we
determined that the disruptions were caused by E-port when
operated at about 1 MW. One positive note is that ECDC in D2
between shots kept the H/D ratio down to 3-4%. This run will be
continued tomorrow.

Scorecard: 8 plasmas
8 fizzles
1 dud (power supply failure)
0 tests
4 aborted and/or screwed up by computers
----------
21 total

-------------------------------------------------------------------------------

Engineering setup and run plan for Tuesday 07 Nov 2000.

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: Granetz/Pedersen
Physics operator: Granetz

ECDC in D2 overnight, ending 2 hours before the run.

Run starts at 09:00 and ends at 17:00.

Power systems as on 1001106024.

Gas setup

fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED


We would like the following gate valves should be enabled:
ECE, VUV, Beast

-------------------------------------------------------------------------------

Run Plan:

Start with 0.8 MA, lower null plasma. We probably need at least 2.5 MW of
ICRF for >200 ms. Ideally we'd like 3+ MW for 0.5 s, but we'll take what
we can get. Assuming we do indeed get H-modes with reversed field, we would
then try it at 1.0 MA, and then at 1.2 MA. Argon puffing will also be
required for JR to get up/down argon profiles.

I'll load segment 1 from 1001106020 (late shot on Monday), and segment 2 from
1001103022 (last plasma on Friday), except I'll set the density to
nl_04=1.0e20 m-2. I've saved this to scratch_disk:[granetz]pcs_1001107000.

-------------------------------------------------------------------------------

Overnight ECDC in D2.

Hybrid coldstart done; no errors found

Loaded shot scratch_disk:[granetz]1001107000 (see preceding note).

-------------------------------------------------------------------------------

ECDC in D2 will be done between shots today.

Shot 01 -- Fizzle. Fields need tweaking.

Next shot: add -15 A to IC_EF4 and -0.5 mT to Br0 offset.

ECDC in D2 is being done between shots.

Shot 02 -- Plasma. Disrupted at t=0.75 s, just as the RF gets up to 2 MW.
It's obviously due to a large impurity injection. Plasma startup
looks good.

Next shot: no PCS changes. (between-shot ECDC is being done)

Shot 03 -- Fizzle. Not surprising after the disruption. Fields look good.

Next shot: no PCS changes. (between-shot ECDC is being done)

Shot 04 -- Fizzle.

Next shot: reduce pre-fill puff by 2 ms (to 20 ms)

Shot 05 -- Fizzle. Gas pressure is still a touch high.

Next shot: reduce pre-fill puff by another 2 ms (to 18 ms)
No ECDC after this shot.

Shot 06 -- Fizzle. Late breakdown...almost went. Gas pressure was a little
too low.

Next shot: raise pre-fill back up to 20 ms.
No ECDC after this shot.

Shot 07 -- Fizzle. Almost made it. Looks like it hit on the outside.

Next shot: raise pre-fill 1 more ms (to 21 ms)
No ECDC after this shot.

Shot 08 -- Dud. No EF2's.

Next shot: no PCS changes.

Shot 09 -- Plasma. 0.8 MA. Disrupted at 0.87 s. Can't see anything obvious
on the videos at the time of the disruption. Prf peaks at 2.0 MW.
H/D=3-4%.

Next shot: no PCS changes. Argon will be enabled.

Shot 10 -- Plasma. Disrupted at t=0.85 s. Prf peaks at 2.0 MW. H/D=4-5%.
Zeff=1.25. No injection observable from antennas, but the
disruptions are definitely due to large injections. Strike points
look fine.

Next shot: reduce TF from 5.37 to 5.20 T to aid H-mode threshold.
ECDC is turned on after this shot.

Shot 11 -- Plasma. Disrupted at t=0.77 s. Prf peaks at 2 MW. Btor=5.24 T.
H/D=4%. Still looks like an injection is killing the plasma.

Next shot: no PCS changes, but turn off the RF for the next shot.

Shot 12 -- Plasma. Good shot. Makes it all the way through rampdown. So it
looks like the disruptions are indeed due to the RF power.
Elongation is increasing late in the shot because of the ZXL
programming. H/D=3%.

Next shot: change ZXL programming to avoid increasing elongation,
turn on J-port transmitter only, with 1 MW of power.
Continue with ECDC between shots.

Shot 13 -- Fizzle. Fields and gas look identical to the previous shot.

Next shot: no changes.

Shot 14 -- Fizzle. Bz might be a touch too negative.

Next shot: raise IC_EF4 by +10 A.

Shot 15 -- Aborted due to computer problems.

Long delay due to computer problems.

Shot 16 -- Plasma. Good shot. J-port gave 1.2 MW. D and E were off.
H/D=3-3.5%, even during the RF pulse. Zeff=1.2. No H-modes.

Next shot: test D, E, and J antennas individually.
ECDC is on between shots.

Shot 17 -- Aborted due to computer problems.

Shot 18 -- Aborted due to computer problems.

Shot 19 -- Aborted due to computer problems. (Actually, at least one PF
supply fired, but we don't know which one(s), because there was
no data acquisition.)

Shot 20 -- Plasma. Disrupted at t=0.62 s, while the E-antenna (only) was
on. I'd say that's pretty conclusive.

Next shot: run D and J together, and keep E off.

Shot 21 -- Plasma. Good shot. J had many faults. D worked very well at
1.07 MW. E also worked well at 0.5 MW by itself (after D and J
turned off). No H-modes.

End of run. (To be continued tomorrow)

Session Leader Comments
Nov 6 2000 06:05:55:217PMRobert GranetzEngineering setup and run plan for Tuesday 07 Nov 2000.

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: Granetz/Pedersen
Physics operator: Granetz

ECDC in D2 overnight, ending 2 hours before the run.

Run starts at 09:00 and ends at 17:00.

Power systems as on 1001106024.

Gas setup

fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED


Assuming no vacuum problems the following gate valves should be enabled:
ECE, VUV, Beast
Nov 6 2000 06:06:10:420PMRobert GranetzRun Plan:

Start with 0.8 MA, lower null plasma. We probably need at least 2.5 MW of
ICRF for >200 ms. Ideally we'd like 3+ MW for 0.5 s, but we'll take what
we can get. Assuming we do indeed get H-modes with reversed field, we would
then try it at 1.0 MA, and then at 1.2 MA. Argon puffing will also be
required for JR to get up/down argon profiles.

I'll load segment 1 from 1001106020 (late shot on Monday), and segment 2 from
1001103022 (last plasma on Friday), except I'll set the density to
nl_04=1.0e20 m-2. I've saved this to scratch_disk:[granetz]pcs_1001107000.
Nov 7 2000 12:30:59:560PM1001107009T. Sunn PedersonPlasma - disrupted as the RF approached 2 MW
Good signs of heating but no sign of an H-mode
yet - as expected.
Nov 7 2000 12:35:56:170PM1001107010T. Sunn PedersonQuite similar to shot 9 - disrupted slightly earlier
I suspect the disruptions are caused by moly injections
from the divertor. There are signs of injections from
the divertor on the mpeg files.
Nov 7 2000 12:37:39:437PM1001107011T. Sunn PedersonSame story - disruption occurred even earlier on this one.
Nov 7 2000 12:54:57:500PM1001107011T. Sunn PedersonNext shot: no RF (to see if the rf is causing the
disruptions)

Nov 7 2000 01:00:10:420PM1001107012T. Sunn PedersonNo disruption, full length plasma.
So the RF heating does cause the
disruptions.


Nov 7 2000 01:00:40:280PM1001107012T. Sunn PedersonNext shot, try 1 MW from J-port antenna.


Nov 7 2000 04:56:37:687PM1001107016T. Sunn PedersonAfter several tries we managed to get a full
shot with 1.2 MW from J antenna which did
not cause any disruptions. We suspect that
the culprit is the E antenna, especially since
we have camera views on D and J, showing no
activity to speak of.



Nov 7 2000 04:59:02:390PM1001107020T. Sunn PedersonAfter numerous computer glitches and a
single power supply glitch we got a plasma
in which we were to launch 1 MW of RF from
E, then 1 MW from D antenna, and finally
1.5 MW from J antenna to see which one
was causing the problem.
The shot disrupted shortly after E antenna
reached 1 MW, confirming our suspicions that
E antenna is the source of the injections.




Nov 7 2000 05:16:34:997PM1001107021T. Sunn PedersonThis shot went the full length - we tried to get
2+ MW out of D and J but only succeeded to get
1 MW out of D whereas J was erratic.
As expected with the low heating power, we did not
get an H-mode.



Physics Operator Comments
Nov 6 2000 05:43:39:203PMRobert GranetzEngineering setup and run plan for Tuesday 07 Nov 2000.

MP #236 H-mode pedestal asymmetry with reversed field

Session leader: Granetz/Pedersen
Physics operator: Granetz

ECDC in D2 overnight, ending 2 hours before the run.

Run starts at 09:00 and ends at 17:00.

Power systems as on 1001106024.

Gas setup

fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bot as is Hybrid DISABLED


Assuming no vacuum problems the following gate valves should be enabled:
ECE, VUV, Beast
Nov 6 2000 05:43:55:717PMRobert GranetzRun Plan:

Start with 0.8 MA, lower null plasma. We probably need at least 2.5 MW of
ICRF for >200 ms. Ideally we'd like 3+ MW for 0.5 s, but we'll take what
we can get. Assuming we do indeed get H-modes with reversed field, we would
then try it at 1.0 MA, and then at 1.2 MA. Argon puffing will also be
required for JR to get up/down argon profiles.

I'll load segment 1 from 1001106020 (late shot on Monday), and segment 2 from
1001103022 (last plasma on Friday), except I'll set the density to
nl_04=1.0e20 m-2. I've saved this to scratch_disk:[granetz]pcs_1001107000.
Nov 7 2000 08:21:06:747AMRobert Granetz Overnight ECDC in D2.

Hybrid coldstart done; no errors found

Loaded shot scratch_disk:[granetz]1001107000 (see preceding note).
Nov 7 2000 09:36:32:920AMRobert GranetzECDC in D2 will be done between shots today.
Nov 7 2000 09:35:42:187AM1001107001Robert GranetzShot 01 -- Fizzle. Fields need tweaking.

Next shot: add -15 A to IC_EF4 and -0.5 mT to Br0 offset.

ECDC in D2 is being done between shots.
Nov 7 2000 09:35:11:530AM1001107002Robert GranetzShot 02 -- Plasma. Disrupted at t=0.75 s, just as the RF gets up to 2 MW.
It's obviously due to a large impurity injection. Plasma startup
looks good.

Next shot: no PCS changes. (between-shot ECDC is being done)
Nov 7 2000 09:51:15:560AM1001107003Robert GranetzShot 03 -- Fizzle. Not surprising after the disruption. Fields look good.

Next shot: no PCS changes. (between-shot ECDC is being done)
Nov 7 2000 10:18:53:030AM1001107004Robert GranetzShot 04 -- Fizzle.

Next shot: reduce pre-fill puff by 2 ms (to 20 ms)
Nov 7 2000 10:40:22:670AM1001107005Robert GranetzShot 05 -- Fizzle. Gas pressure is still a touch high.

Next shot: reduce pre-fill puff by another 2 ms (to 18 ms)
No ECDC after this shot.
Nov 7 2000 10:50:27:077AM1001107006Robert GranetzShot 06 -- Fizzle. Late breakdown...almost went. Gas pressure was a little
too low.

Next shot: raise pre-fill back up to 20 ms.
No ECDC after this shot.
Nov 7 2000 11:24:16:967AM1001107007Robert GranetzShot 07 -- Fizzle. Almost made it. Looks like it hit on the outside.

Next shot: raise pre-fill 1 more ms (to 21 ms)
No ECDC after this shot.
Nov 7 2000 11:24:06:577AM1001107008Robert GranetzShot 08 -- Dud. No EF2's.

Next shot: no PCS changes.
Nov 7 2000 12:16:35:280PM1001107009Robert GranetzShot 09 -- Plasma. 0.8 MA. Disrupted at 0.87 s. Can't see anything obvious
on the videos at the time of the disruption. Prf peaks at 2.0 MW.
H/D=3-4%.

Next shot: no PCS changes. Argon will be enabled.
Nov 7 2000 12:16:08:687PM1001107010Robert GranetzShot 10 -- Plasma. Disrupted at t=0.85 s. Prf peaks at 2.0 MW. H/D=4-5%.
Zeff=1.25. No injection observable from antennas, but the
disruptions are definitely due to large injections. Strike points
look fine.

Next shot: reduce TF from 5.37 to 5.20 T to aid H-mode threshold.
ECDC is turned on after this shot.
Nov 7 2000 12:34:55:687PM1001107011Robert GranetzShot 11 -- Plasma. Disrupted at t=0.77 s. Prf peaks at 2 MW. Btor=5.24 T.
H/D=4%. Still looks like an injection is killing the plasma.

Next shot: no PCS changes, but turn off the RF for the next shot.
Nov 7 2000 01:01:31:577PM1001107012Robert GranetzShot 12 -- Plasma. Good shot. Makes it all the way through rampdown. So it
looks like the disruptions are indeed due to the RF power.
Elongation is increasing late in the shot because of the ZXL
programming. H/D=3%.

Next shot: change ZXL programming to avoid increasing elongation,
turn on J-port transmitter only, with 1 MW of power.
Continue with ECDC between shots.
Nov 7 2000 01:37:22:217PM1001107013Robert GranetzShot 13 -- Fizzle. Fields and gas look identical to the previous shot.

Next shot: no changes.
Nov 7 2000 01:46:47:467PM1001107014Robert GranetzShot 14 -- Fizzle. Bz might be a touch too negative.

Next shot: raise IC_EF4 by +10 A.
Nov 7 2000 02:15:20:717PM1001107015Robert GranetzLong delay due to computer problems.
Nov 7 2000 02:41:14:280PM1001107015Robert GranetzShot 15 -- Aborted due to computer problems.
Nov 7 2000 03:06:46:967PM1001107016Robert GranetzShot 16 -- Plasma. Good shot. J-port gave 1.2 MW. D and E were off.
H/D=3-3.5%, even during the RF pulse. Zeff=1.2. No H-modes.

Next shot: test D, E, and J antennas individually.
ECDC is on between shots.
Nov 7 2000 04:01:45:403PM1001107017Robert GranetzShot 17 -- Aborted due to computer problems.
Nov 7 2000 03:37:33:310PM1001107018Robert GranetzShot 18 -- Aborted due to computer problems.
Nov 7 2000 04:44:58:437PM1001107019Robert GranetzShot 19 -- Aborted due to computer problems. (Actually, at least one PF
supply fired, but we don't know which one(s), because there was
no data acquisition.)
Nov 7 2000 04:54:08:043PM1001107020Robert GranetzShot 20 -- Plasma. Disrupted at t=0.62 s, while the E-antenna (only) was
on. I'd say that's pretty conclusive.

Next shot: run D and J together, and keep E off.
Nov 7 2000 05:22:50:153PM1001107021Robert GranetzShot 21 -- Plasma. Good shot. J had many faults. D worked very well at
1.07 MW. E also worked well at 0.5 MW by itself (after D and J
turned off). No H-modes.

End of run. (To be continued tomorrow)

Engineering Operator Comments
ShotTimeTypeStatusComment
108:56:54:187AMPlasmaOk
209:22:25:670AMPlasmaOk
309:44:13:780AMPlasmaOk
410:05:53:780AMPlasmaOk
510:27:23:140AMPlasmaOk
610:43:27:467AMPlasmaOk
710:58:23:280AMPlasmaOk
811:14:46:013AMPlasmaOk
911:32:30:030AMPlasmaOk
1011:56:56:357AMPlasmaOk
1112:24:27:450PMPlasmaOk
1212:51:07:827PMPlasmaOk
1301:16:59:043PMPlasmaOk
1401:41:34:450PMPlasmaOk
1502:03:54:560PMPlasmaBadno power shot Physop died
1602:43:33:373PMPlasmaOk
1803:33:26:357PMPlasmaBadno power shot , computer failures
1904:33:21:153PMPlasmaBadOnly TF power supply turned on
2004:45:52:170PMPlasmaOk
2105:00:45:797PMPlasmaOk