Alcator C-Mod Run 1040315 Information

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Miniproposals
Miniproposal:341
Date Filed: 6/4/2003
Title:Power Absorption in ITBs
First Author:Catherine Fiore
Session Leader:Catherine Fiore (shots 1-18)

Operators
Session leader(s):Catherine Fiore
Physics operator(s):Steve Wolfe
Engineering operator(s):Bill Cochran,Bill Byford,Bill Parkin

Engineering Operator Run Comment
MP#341 Power Absorption in ITB

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:03:490PM
Author: Catherine Fiore
SL Fiore
PO Wolfe

In this run we hope to complete MP 341 which ended prematurely when we lost
the FMIT 4 output tube. We will start with shot 29 from 1040309 and
re-establish the ITB from that shot. We will start with somewhat lower
central ICRF power than on shot 29, and scan up until we lose the ITB.
Once this is done, we should change the off axis power and repeat the
central power scan. If time allows, we can try this at the higher field.
----------------
Disappointing run. There were severe data system problems which
seriously delayed the start of the run. Once we began making plasmas, we
could not sustain the H-modes after the ITBs started to form. It seemed like
radiation was too high. We only had a few shots to try to tune things in,
however. We made no progress on MP341.

Shot summary

1040310001 Data system test. Data system failure.

1040310002-1004031006 Data system tests.

1040310007 First plasma. Full RF power was not available, because we turned
it off while we were sorting out the data system. Despite the lower rf
power, we got several short H-modes. No ITBs.

1040310008 One good H-mode, then a back transition. An ITB was forming just
before the back tranisition. 2 MW total from D and E, 0.8 MW from J port.
We'll try to go to slightly more power off axis to try to optimize the ITB.

1040310009 Data system failure. We probably had a brief ITB.

1040310010-1040310012 Data system tests.

1040315013 RF power was lower than requested. H-modes with multiple back
transitions. No ITB. We'll try to get the correct rf power.

1040315014 H-mode with an ITB started but it had a back transition
before J-port fired. We will try a little more power from D and E.

1040315015 H-mode with an ITB started but it had a back transition before
J-port fired. It lasted a little longer than the previous shot. We will
try a little more power from D and E.

1040315016 Hmode with an ITB started but it had a back transition before
J-port fired. We will try to fire J-port before the back transition.

1040315017 Hmode with an ITB started but it again had a back transition.
This time J-port came on earlier, and did not affect the ITB rise.
The radiation is higher this week than last week, and may be the critical
difference. We will turn off the argon and adjust the triangularity at the
same time to maximize the confusion.

1040314018 Hmode with an ITB started but it again had a back transition.
J-port did not fire. Problems with FMIT 4 ends the run.

Physics Operator Summaries
Entered: Jul 7 2004 04:36:49:507PM
Author: Steve Wolfe
Physics Operator Summary for Monday, 1040315

MP#341: Power absorption in ITB
SL: Fiore
PO: wolfe
EO: Cochran,Byford,Parkin (the Bill's)

Engineering setup:
------------------
Run begins at 09:00 (or as close as possible), ends at 17:00

Power supplies as on 1040309013

Gas System Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
leave B-side upper with 15 psi He3 Hybrid DISABLED (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)
fill NINJA (lower cap) with 8 psi D2

Gate valve permissives for the usual suspects (ECE, VUV, DNB) assuming no
vacuum problems

RF: Transmitters #1,2,3 and 4 in RUN-ON by 08:00

Run Plan:
---------

Finish off the MP begun on Tuesday, 1040309. Specifically, we still need to
determine the highest on-axis power we can use without destroying the
high-field side resonance ITB (4.5T), and document the confinement
properties. Then we can proceed to the low-field side resonance, using the
70MHz for off-axis heating at B~5.6T and 80MHz on-axis.

We will start with a shot like 1040309029, which had 1.5MW of on-axis
70MHz. We will revisit a few lower power cases, to verify reproducibility of
last week's results, in view of the fact that we are now one week after the
boronization. We will then increase the on-axis power until we get clear
indication of loss of the core barrier. We will also try varying the off-axis
power to see how that affects the amount of core heating allowed.

If we complete the 4.5 T experiments, we will continue the MP by going through
the same sequence for low-field side resonance at 5.6T.


Results
-------

We got off to a late start because of a failure of the gigabit ethernet switch
that connects alcdaq, alchome, alcpc1, red, daqa, cmoda, etc. to rest of the
universe. This was apparently fixed at around 10:30AM, but additional computer
problems prevented us from taking a successful test shot until 1:30PM. The
first plasma shot was #7, taken at about 1:35PM.

Computer problems continued during the run, and after shot#9 Tom again
reconfigured alcdaq, this time as a single processor. In parallel, Josh
brought cmodws34 over to the rack and got it ready to plug in as a
replacement, as it was before the arrival of alcserv3 and alcserv4.
We ran with alcdaq for the remainder of the run, with the only data problem
being due to loss of another ethernet connection (see below). This does NOT
mean the server problem has been fixed.

We got decent ITB's but they all dropped out (H->L) around 1.1 to
1.2sec. Moving the on-axis RF earlier did not help. Neither did turning off
the argon. The 2pi foil indicated radiated power up to 4MW, with a maximum
power of 2.4MW from D+E. We may be ready for another boronization.

After shot#16 we lost communication with pcdaqmhd1. We tried power cycling the
crate in the cell, but the problem turned out to be the fiber to copper
ethernet connection in the setup lab. Henry replaced the bad unit and we
resumed operation.

J-port (FMIT#4) had some sort of fuse loss after shot #18, and we terminated
the run at 16:55.

Between the computer problems and the high radiation, no progress was made on
the MP today. We have scheduled another try for tomorrow.

Scorecard:
----------

Tests 9
Duds 0
Fizzles 0
Plasmas 9
------ --
shots 18

Session Leader Comments
Mar 15 2004 10:27:28:293AMCatherine FioreIn this run we hope to complete MP 341 which ended prematurely when we lost the FMIT 4 output tube. We
will start with shot 29 from 1040309 and re-establish the ITB from that shot. We will start with somewhat lower
central ICRF power than on shot 29, and scan up until we lose the ITB.

Once this is done, we should change the off axis power and repeat the central power scan.

If time allows, we can try this at the higher field.
Mar 15 2004 11:05:24:990AM1040315001Catherine FioreData system test. Probably unsuccessful. No ITB
Mar 15 2004 01:37:12:627PM1040315007Catherine FioreFirst plasma. Full RF power was not available, because we turned it off while we were sorting out the
data system. Despite the lower rf power, we got several short H-modes. No ITBs.
Mar 15 2004 02:08:07:263PM1040315008Catherine FioreOne good H-mode, then a back transition. An ITB was forming just before the back tranisition.
2 MW total from D and E, 0.8 MW from J port. We'll try to go to slightly more power off axis
to try to optimize the ITB.
Mar 15 2004 03:15:45:550PM1040315009Catherine Fiore Data system failure. We probably had a brief ITB.
Mar 15 2004 03:23:41:143PM1040315013Catherine Fiore RF power was lower than requested. H-modes with multiple back transitions.
No ITB. We'll try to get the correct rf power.
Mar 15 2004 03:36:43:920PM1040315014Catherine FioreHmode with an ITB started but it had a back transition before J-port fired.
We will try a little more power from D and E.
Mar 15 2004 03:50:26:880PM1040315015Catherine FioreHmode with an ITB started but it had a back transition before J-port fired. It
lasted a little longer than the previous shot. We will try a little more power from D and E.
Mar 15 2004 04:03:23:673PM1040315016Catherine FioreHmode with an ITB started but it had a back transition before J-port fired. We
will try to fire J-port before the back transition.
Mar 15 2004 04:48:11:587PM1040315017Catherine FioreHmode with an ITB started but it again had a back transition. This time J-port came on earlier, and did
not affect the ITB rise. The radiation is higher this week than last week, and may be the critical
difference. We will turn off the argon and adjust the triangularity at the same time to maximize the confusion.
Mar 16 2004 09:20:23:490AM1040315018Catherine FioreHmode with an ITB started but it again had a back transition. J-port did not fire.
Problems with FMIT 4 ends the run.

Physics Operator Comments
Mar 15 2004 10:05:50:910AMSteve WolfeDelayed start due to network switch outage
For first shot, I have loaded 1040309029, 0.8MA ITB from last Tuesday.

Mar 15 2004 10:27:08:950AMSteve WolfeRun Plan and Engineering Setup for Monday 15-Mar-2004

MP#341 Power Absorption in ITB
SL: Fiore
PO: wolfe

Engineering setup:
------------------
Run begins at 09:00 (or as close as possible), ends at 17:00

Power supplies as on 1040309013

Gas System Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
leave B-side upper with 15 psi He3 Hybrid DISABLED (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)
fill NINJA (lower cap) with 8 psi D2

Gate valve permissives for the usual suspects (ECE, VUV, DNB) assuming no
vacuum problems

RF: Transmitters #1,2,3 and 4 in RUN-ON by 08:00

Run Plan:
---------

Finish off the MP begun on Tuesday, 1040309. Specifically, we still need to
determine the highest on-axis power we can use without destroying the
high-field side resonance ITB (4.5T), and document the confinement
properties. Then we can proceed to the low-field side resonance, using the
70MHz for off-axis heating at B~5.6T and 80MHz on-axis.

We will start with a shot like 1040309029, which had 1.5MW of on-axis
70MHz. We will revisit a few lower power cases, to verify reproducibility of
last week's results, in view of the fact that we are now one week after the
boronization. We will then increase the on-axis power until we get clear
indication of loss of the core barrier. We will also try varying the off-axis
power to see how that affects the amount of core heating allowed.

If we complete the 4.5 T experiments, we will continue the MP by going through
the same sequence for low-field side resonance at 5.6T.


Mar 15 2004 10:51:53:730AM1040315001Steve Wolfeshot 1: No power cycle, data system test after all the
computer problems this morning

First try failed, bringing it around again after Henry rebooted
a different switch.

Second try also failed. Will try again after Tom says so.
Mar 15 2004 11:06:21:930AM1040315001Steve Wolfeshot 1: Third time around at shot 1040315001
Data coming through. looks ok.
No actually it got partway through and failed in store.
Scopes are hanging up.

next shot: We'll see ...
Mar 15 2004 11:47:12:337AM1040315002Steve Wolfeshot 2: Data system test (no power).
Hangs in init. Josh is typing at it.
dpcs wasn't communicating; jas rebooted it.
Back out of init.

dpcs is fsck'ing /usr over nfs and taking a long time.
Disable dpcs and try again.
Mar 15 2004 11:53:18:177AM1040315002Steve Wolfeshot 2: Failed to ok check-to-pulse.
No good.

Mar 15 2004 12:30:28:653PM1040315003Steve Wolfeshot 3: Data test again.
Not making it through init.

Steve is turning off the filaments in the RF to
conserve filament life.
Mar 15 2004 12:54:29:903PM1040315003Steve Wolfeshot 3: Tom is running test "cycles" by hand. He seems to be slowly
getting data for shot #3.
Mar 15 2004 01:06:19:537PM1040315004Steve Wolfeshot 4: Tom is running test "cycles" by hand.
Got pretty much all the data on shot#4

Mar 15 2004 01:26:59:933PM1040315006Steve Wolfeshot 6: No power cycle run from state
got gas.
Data coming through
looks good.

next shot: go for plasma
Mar 15 2004 01:37:34:627PM1040315007Steve Wolfeshot 7: go for plasma, rf will be off while filaments warm back up.
We will have D-port.
plasma full length, some h-modes.
No ITB. Just under 1MW from D-port only.

next shot: repeat, with more RF's
Mar 15 2004 01:48:46:727PM1040315007Steve Wolfeshot 8: repeat, with more RF's
This shot should get D+E, still not turning on J

Holding for a power room access so RF can look at #3 and 4
Mar 15 2004 02:04:46:803PM1040315008Steve Wolfeshot 8: repeat, with more RF's
Prior to shot 8, cycle the dalsa routine.

plasma full length, got an eda until 1.15sec,
before J comes on. looks like d faulted.
Got the start of an ITB, then it died.

next shot: ask for a little more from D+E
Mar 15 2004 02:20:05:397PM1040315009Steve Wolfeshot 9: ask for a little more from D+E
plasma full length,

Server hung again.
We will be down for at least an hour, possibly for the rest of the day.
Mar 15 2004 02:50:36:220PM1040315011Steve Wolfeshot 10: Tom is running a manual cycle again, while Josh
gets cmodws34 ready to go.

Mar 15 2004 03:13:49:810PM1040315011Steve Wolfeshot 13: Tom says try for a power shot.
Mar 15 2004 03:23:25:703PM1040315013Steve Wolfeshot 13: Tom says try for a power shot.
plasma full length. three h-modes (2 short and one long)
No E-port RF , no ITB

next shot: Try again, with E-port
Mar 15 2004 03:36:28:480PM1040315014Steve Wolfeshot 14: Try again with E-port this time.
plasma full length, drops out of eda at 1.05sec.
Starting an ITB, then it drops out.


next shot: try for more D+E power, drop Ar from 40->30msec
Mar 15 2004 03:51:13:493PM1040315015Steve Wolfeshot 15: try for more D+E power, drop Ar from 40->30msec
plasma full length. eda to 1.17sec
ITB is just starting.


next shot: More from D+E
Mar 15 2004 04:02:27:860PM1040315016Steve Wolfeshot 16: More from D+E
plasma full length, eda to 1.14sec

next shot: bring J-port on earlier
Mar 15 2004 04:41:18:980PM1040315017Steve Wolfeshot 17: bring J-port on earlier
Prior to this shot, we lost connection to pcdaqmhd1.
Rebooting in the cell did not help. It turned out to be
a bad fiber to copper ethernet connection in the setup lab.
Henry replaced it and we're ready to try a shot.

plasma full length, eda dies at almost exactly the same time.

next shot: turn off the argon.
Mar 15 2004 04:56:15:087PM1040315018Steve Wolfeshot 18: turn off the argon. Also, decrease triang (rxl from -.02 to -.01)
plasma full length, eda/itb ends at 1.11; there's also a second ITB.
No J-port.

Screen trip on #4. RF'ers are investigating

Engineering Operator Comments
ShotTimeTypeStatusComment
110:59:44:900AMTestOk
312:41:59:677PMTestBad
501:10:27:620PMTestOk
601:19:30:030PMTestOk
701:30:46:427PMPlasmaOk
801:57:19:320PMPlasmaOk
902:11:47:910PMPlasmaOk
1002:43:48:677PMTestBad
1102:48:04:620PMTestBad
1303:16:16:707PMPlasmaOk
1403:28:45:840PMPlasmaOk
1503:44:37:027PMPlasmaOk
1603:58:48:227PMPlasmaOk
1704:36:25:703PMPlasmaOk
1804:49:19:290PMPlasmaOk