Alcator C-Mod Run 1000331 Information

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Miniproposals
Miniproposal:
Date Filed:
Title:
First Author:
Session Leader:Ian Hutchinson (shots 1-16)
Session Leader:Steve Wolfe (shots 1-16)

Operators
Session leader(s):Ian Hutchinson,Steve Wolfe
Physics operator(s):Jim Irby
Engineering operator(s):Bill Cochran,Gary Dekow,Frank Silva

Engineering Operator Run Comment
Reverse Field Start up/Irby,Silva

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Physics Operator Summaries
Entered: Jul 7 2004 04:37:10:210PM
Author: To Be Determined
Run Summary for 1000331

PO: Irby
SL: Hutch, Wolfe
EO: Silva, Cochran, Dekow

The main goals for today's run were to continue conditioning the
machine and bring up diagnostics. The startup in reversed field
fine tuned yesterday proved to be as robust today as we have found
with the field in the normal direction.

Though we got several long lasting discharges, the plasmas are still
very dirty and primarily fueled from the walls. We had only one
brief period on shot 12 in which the density was under control.
The MARFE went away and injections ceased during this period. The VUV
indicates a large amount of carbon and HiReX bright moly emission
at least during periods of low density. The H to D ratios ranged
from 0.4 to greater than 1, increasing during the day.
Now that we have reliable startup with long discharge durations, we
should be able to clean up the machine quickly.


Problems:

The EF2 breaker we first had problems with yesterday had to be
replaced before the run.

Score:
plasma duration Comment

1 TF test
2 EF2 breaker test
3 0.36
4 0.90 H to D 0.4
5 1.65
6 fizzle (68kA)
7 fizzle (40kA)
8 0.41
9 dud EF4 tweak in wrong direction
10 0.39 EF4 detweaked --- increased Br0
11 1.48
12 1.36 lost MARFE -- had density control
13 1.48
14 1.6 changed rampdown
15 fizzle (40kA)
16 1.63



Details:

Entry display output on Fri Mar 31 22:16:11 2000


----------------------------------------------------------------------------
1000331xxx irby PHYSICS_OPERATOR Mar 31 2000 8:09:54:840AM
. . . . . . . . . . . . . . . . . . . .
Loaded last shot from yesterday, 1000330026

Did cold start


----------------------------------------------------------------------------
1000331xxx irby PHYSICS_OPERATOR Mar 31 2000 8:17:48:000AM
. . . . . . . . . . . . . . . . . . . .
Run plan is to continue cleaning up machine and bringing diagnostics
on line.

Hope to have more spectroscopy data today looking
for Cu, Fe, etc.
----------------------------------------------------------------------------
1000331001 irby PHYSICS_OPERATOR Mar 31 2000 8:55:31:966AM
. . . . . . . . . . . . . . . . . . . .
First shot is TF only test.

Then we will have to break for about 1 hour to fix EF2 breaker

All TF taps look very good: turn #79 about 1.4 uOhm.

We ran both gas puffs under hybrid control. Gas coming into
machine looks very good on RGA (all D2).

We are getting an increase in mass 18 in CHECK. Will not
enable any gatevalves for the next shot: VUV or ECE??
----------------------------------------------------------------------------
1000331002 irby PHYSICS_OPERATOR Mar 31 2000 10:41:35:186AM
. . . . . . . . . . . . . . . . . . . .
EF2 test only.

No gatevalves enabled. No mass 18.

EF2 looks good.

Rejean manually opened ECE valve after shot and we saw the mass 18 go
up.
----------------------------------------------------------------------------
1000331002 silva POWER_SYSTEMS Mar 31 2000 11:49:29:623AM
. . . . . . . . . . . . . . . . . . . .
The EF2U cabinet D power supply 480Vac main feeder breaker
mounted inside the power supply would not latch closed.
The problem was found to be a mechanical failure inside the
breaker. The breaker was then replaced with a spare.
----------------------------------------------------------------------------
1000331003 wolfe SESSION_LEADER Mar 31 2000 10:59:07:513AM
. . . . . . . . . . . . . . . . . . . .
shot#3: First plasma attempt.
plasma - .36sec. CII ~.005mW/cm2/ster
lots of injections, leading to a disruption
----------------------------------------------------------------------------
1000331003 irby PHYSICS_OPERATOR Mar 31 2000 11:05:22:950AM
. . . . . . . . . . . . . . . . . . . .
Plasma; about 360 ms

Only enabled VUV: Still have mass 18 before shot



Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 5.7942 26.5702 106.9892
dIp/dt (kA/ms): 1.0151 3.1814 3.8172 7.6299
pressure (mTorr): 0.0491 0.0496 0.0508 0.0424
Bz0 (mT): 2.6031 0.9247 -2.2697 -22.6940
Br0 (mT): 0.3669 0.6496 0.9760 2.0665

oh1: 0.2662 uohm
oh2u: 0.1359 uohm
oh2l: 0.2347 uohm

Ricky's movie shows MARFE move up inner wall to top of machine followed by
a couple of UFOs and the disruption

Jim's first look at impurities indicates lots of carbon. Carbon II at 0.01 s
is pretty low: .004.

Gas valve off at 0.137 s, but density continues to rise at somewhat lower rate

H to D bottoms out at around 15%

----------------------------------------------------------------------------
1000331004 wolfe SESSION_LEADER Mar 31 2000 11:17:29:106AM
. . . . . . . . . . . . . . . . . . . .
shot 4: plasma to 0.9sec, density dropping down toward program value after 0.8sec
It looks like the marfe disappears at about the same time as the density begins to
drop.
----------------------------------------------------------------------------
1000331004 irby PHYSICS_OPERATOR Mar 31 2000 11:39:48:170AM
. . . . . . . . . . . . . . . . . . . .
Repeat last shot

Plasma for 0.94 seconds

VUV and ECE gatevalves enabled

Looks like we are cleaning things up. Nicely diverted. MARFE at
top of machine goes away and density goes down. Peak density twice
what we asked for.

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 106.9664
dIp/dt (kA/ms): 1.2727 3.1791 3.5595 7.5016
pressure (mTorr): 0.0485 0.0485 0.0496 0.0410
Bz0 (mT): 3.0298 0.1309 -1.4030 -22.2139
Br0 (mT): 0.4974 0.7137 0.9789 1.7890


H to D about 0.4

Note that DNB has been running with the C-Mod cycle for the last
few shots.
----------------------------------------------------------------------------
1000331005 irby PHYSICS_OPERATOR Mar 31 2000 11:57:24:296AM
. . . . . . . . . . . . . . . . . . . .
Plasma for 1.647 seconds


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5702 109.5606
dIp/dt (kA/ms): 1.2716 3.3085 3.8127 6.8691
pressure (mTorr): 0.0485 0.0480 0.0491 0.0410
Bz0 (mT): 3.2477 0.3841 -2.3055 -21.7856
Br0 (mT): 0.7135 1.0341 0.9833 1.5873

H to D at 1.0 s is 0.75

Got into rampdown.

----------------------------------------------------------------------------
1000331006 irby PHYSICS_OPERATOR Mar 31 2000 12:10:11:670PM
. . . . . . . . . . . . . . . . . . . .
Repeat

Waited 20 minutes between shots, vs 25 last shot

Plasma for 24 ms or so, 68 kA

Rapid rise in CII after 20 ms

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.4111 26.5702 21.3592
dIp/dt (kA/ms): 1.2739 3.4345 3.3040 -4.5790
pressure (mTorr): 0.0485 0.0491 0.0485 0.0424
Bz0 (mT): 3.4408 1.2651 -1.0058 -19.4101
Br0 (mT): 0.4342 0.7853 1.0820 0.4148

----------------------------------------------------------------------------
1000331007 irby PHYSICS_OPERATOR Mar 31 2000 12:42:00:480PM
. . . . . . . . . . . . . . . . . . . .
20 minutes wait

PCS repeat, though Ian suggests Br0 may need a tweak if this one doesn't go.

plasma but only 43 kA, 20 ms

----------------------------------------------------------------------------
1000331008 silva POWER_SYSTEMS Mar 31 2000 12:57:13:560PM
. . . . . . . . . . . . . . . . . . . .
OH2U,OH2L commutation fault, OH1 self powered circuit fired
Voltage spike on OH1 bus at time of disruption appears to be
the source of the fault.
----------------------------------------------------------------------------
1000331008 irby PHYSICS_OPERATOR Mar 31 2000 1:05:49:390PM
. . . . . . . . . . . . . . . . . . . .
EF4 from +1310 to +1280.

Forgot to load it!!

RGA impurity levels below pre-run levels for this shot

Plasma for 0.41 s. Some runaways.

Lost it on crossover
----------------------------------------------------------------------------
1000331009 irby PHYSICS_OPERATOR Mar 31 2000 1:12:51:216PM
. . . . . . . . . . . . . . . . . . . .
EF4 should really be at +1280 amps this shot

Added 1 ms to pre-puff

DuD!

Looks like we took EF4 the wrong way.

----------------------------------------------------------------------------
1000331010 irby PHYSICS_OPERATOR Mar 31 2000 1:40:09:326PM
. . . . . . . . . . . . . . . . . . . .
EF4 back to +1310 Amps

Br0 from -2.5 mT to -1.5 mT

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 109.5606
dIp/dt (kA/ms): 1.2705 3.3063 4.1976 6.9952
pressure (mTorr): 0.0502 0.0496 0.0508 0.0424
Bz0 (mT): 1.7570 -0.3335 -3.0127 -21.0392
Br0 (mT): 1.4693 1.7684 2.2450 3.0543

We got more Br0

Looks like MARFE is starting before crossover. Lots of UFOs.

Low RGA levels before shot.

CII level at 0.01 s is .004
----------------------------------------------------------------------------
1000331011 irby PHYSICS_OPERATOR Mar 31 2000 2:03:09:750PM
. . . . . . . . . . . . . . . . . . . .
PCS Repeat

IGT at 6.3e-7 at init

Plasma for 1.48 seconds

Still getting about twice the density we are asking for.

CII 0.05 at .01 s

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 99.2067
dIp/dt (kA/ms): 1.2717 3.1791 3.9432 6.6148
pressure (mTorr): 0.0502 0.0519 0.0508 0.0444
Bz0 (mT): 2.0653 0.3798 -1.6186 -21.1178
Br0 (mT): 1.5637 1.6137 1.8969 3.1692

----------------------------------------------------------------------------
1000331012 irby PHYSICS_OPERATOR Mar 31 2000 2:22:59:420PM
. . . . . . . . . . . . . . . . . . . .
PCS repeat

IGT at 8.1e-7 at init

Plasma for 1.36 s

Reached programmed density late in shot. Something was burned off!
2Pi drops and injections stop.

John says lots of moly: "It's really up there"


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 23.9534 96.5898
dIp/dt (kA/ms): 1.2728 3.0508 3.5584 6.6115
pressure (mTorr): 0.0514 0.0519 0.0525 0.0459
Bz0 (mT): 2.1359 -0.4380 -1.4667 -19.5610
Br0 (mT): 1.5858 1.6276 1.7492 3.1725

Note that Bz0 is jumping +-0.4 mT. Br0 pretty stable.

H to D 1.0 at 1.0 seconds and rising
----------------------------------------------------------------------------
1000331013 irby PHYSICS_OPERATOR Mar 31 2000 2:32:45:670PM
. . . . . . . . . . . . . . . . . . . .
PCS repeat

IGT 8.9e-7 Torr at init

Plasma for 1.48 s

MARFE is back

No density control again

Moly early but went away later in shot (higher density?)

----------------------------------------------------------------------------
1000331014 irby PHYSICS_OPERATOR Mar 31 2000 2:56:21:856PM
. . . . . . . . . . . . . . . . . . . .
Enabled argon puff for John

Changed clearin, zxl, rcur, and rxu to start rampdown at about 1.3 s
instead of 1.5

Plasma for 1.6 s

Rampdown is much better

CII at .005 at 0.01 s

oh1: 0.2398 uohm
oh2u: 0.1331 uohm
oh2l: 0.3124 uohm

----------------------------------------------------------------------------
1000331015 irby PHYSICS_OPERATOR Mar 31 2000 3:14:51:576PM
. . . . . . . . . . . . . . . . . . . .
Steve wants to put less demand on EF1:

Dropped ZXU from 0.048 to 0.025
Set RXU to 0 across shot

40 kA plasma


----------------------------------------------------------------------------
1000331016 irby PHYSICS_OPERATOR Mar 31 2000 3:35:31:780PM
. . . . . . . . . . . . . . . . . . . .
PCS repeat

plasma for 1.63 seconds

EF1s still railed

CII .004 at 0.01 s

Density still out of control

Jim sees a little Fe, but should not be our problem

Steve claims we were "a little double nulled"

Session Leader Comments
Mar 31 2000 10:59:07:513AM1000331003Steve Wolfeshot#3: First plasma attempt.
plasma - .36sec. CII ~.005mW/cm2/ster
lots of injections, leading to a disruption
Mar 31 2000 11:17:29:107AM1000331004Steve Wolfeshot 4: plasma to 0.9sec, density dropping down toward program value after 0.8sec
It looks like the marfe disappears at about the same time as the density begins to
drop.

Physics Operator Comments
Mar 31 2000 08:09:54:840AMJim IrbyLoaded last shot from yesterday, 1000330026

Did cold start


Mar 31 2000 08:17:48:000AMJim IrbyRun plan is to continue cleaning up machine and bringing diagnostics
on line.

Hope to have more spectroscopy data today looking
for Cu, Fe, etc.
Mar 31 2000 08:55:31:967AM1000331001Jim IrbyFirst shot is TF only test.

Then we will have to break for about 1 hour to fix EF2 breaker

All TF taps look very good: turn #79 about 1.4 uOhm.

We ran both gas puffs under hybrid control. Gas coming into
machine looks very good on RGA (all D2).

We are getting an increase in mass 18 in CHECK. Will not
enable any gatevalves for the next shot: VUV or ECE??
Mar 31 2000 10:41:35:187AM1000331002Jim IrbyEF2 test only.

No gatevalves enabled. No mass 18.

EF2 looks good.

Rejean manually opened ECE valve after shot and we saw the mass 18 go
up.
Mar 31 2000 11:05:22:950AM1000331003Jim IrbyPlasma; about 360 ms

Only enabled VUV: Still have mass 18 before shot



Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 5.7942 26.5702 106.9892
dIp/dt (kA/ms): 1.0151 3.1814 3.8172 7.6299
pressure (mTorr): 0.0491 0.0496 0.0508 0.0424
Bz0 (mT): 2.6031 0.9247 -2.2697 -22.6940
Br0 (mT): 0.3669 0.6496 0.9760 2.0665

oh1: 0.2662 uohm
oh2u: 0.1359 uohm
oh2l: 0.2347 uohm

Ricky's movie shows MARFE move up inner wall to top of machine followed by
a couple of UFOs and the disruption

Jim's first look at impurities indicates lots of carbon. Carbon II at 0.01 s
is pretty low: .004.

Gas valve off at 0.137 s, but density continues to rise at somewhat lower rate

H to D bottoms out at around 15%

Mar 31 2000 11:39:48:170AM1000331004Jim IrbyRepeat last shot

Plasma for 0.94 seconds

VUV and ECE gatevalves enabled

Looks like we are cleaning things up. Nicely diverted. MARFE at
top of machine goes away and density goes down. Peak density twice
what we asked for.

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 106.9664
dIp/dt (kA/ms): 1.2727 3.1791 3.5595 7.5016
pressure (mTorr): 0.0485 0.0485 0.0496 0.0410
Bz0 (mT): 3.0298 0.1309 -1.4030 -22.2139
Br0 (mT): 0.4974 0.7137 0.9789 1.7890


H to D about 0.4

Note that DNB has been running with the C-Mod cycle for the last
few shots.
Mar 31 2000 11:57:24:297AM1000331005Jim IrbyPlasma for 1.647 seconds


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5702 109.5606
dIp/dt (kA/ms): 1.2716 3.3085 3.8127 6.8691
pressure (mTorr): 0.0485 0.0480 0.0491 0.0410
Bz0 (mT): 3.2477 0.3841 -2.3055 -21.7856
Br0 (mT): 0.7135 1.0341 0.9833 1.5873

H to D at 1.0 s is 0.75

Got into rampdown.

Mar 31 2000 12:10:11:670PM1000331006Jim IrbyRepeat

Waited 20 minutes between shots, vs 25 last shot

Plasma for 24 ms or so, 68 kA

Rapid rise in CII after 20 ms

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.4111 26.5702 21.3592
dIp/dt (kA/ms): 1.2739 3.4345 3.3040 -4.5790
pressure (mTorr): 0.0485 0.0491 0.0485 0.0424
Bz0 (mT): 3.4408 1.2651 -1.0058 -19.4101
Br0 (mT): 0.4342 0.7853 1.0820 0.4148

Mar 31 2000 12:42:00:480PM1000331007Jim Irby20 minutes wait

PCS repeat, though Ian suggests Br0 may need a tweak if this one doesn't go.

plasma but only 43 kA, 20 ms

Mar 31 2000 01:05:49:390PM1000331008Jim IrbyEF4 from +1310 to +1280.

Forgot to load it!!

RGA impurity levels below pre-run levels for this shot

Plasma for 0.41 s. Some runaways.

Lost it on crossover
Mar 31 2000 01:12:51:217PM1000331009Jim IrbyEF4 should really be at +1280 amps this shot

Added 1 ms to pre-puff

DuD!

Looks like we took EF4 the wrong way.

Mar 31 2000 01:40:09:327PM1000331010Jim IrbyEF4 back to +1310 Amps

Br0 from -2.5 mT to -1.5 mT

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 109.5606
dIp/dt (kA/ms): 1.2705 3.3063 4.1976 6.9952
pressure (mTorr): 0.0502 0.0496 0.0508 0.0424
Bz0 (mT): 1.7570 -0.3335 -3.0127 -21.0392
Br0 (mT): 1.4693 1.7684 2.2450 3.0543

We got more Br0

Looks like MARFE is starting before crossover. Lots of UFOs.

Low RGA levels before shot.

CII level at 0.01 s is .004
Mar 31 2000 02:03:09:750PM1000331011Jim IrbyPCS Repeat

IGT at 6.3e-7 at init

Plasma for 1.48 seconds

Still getting about twice the density we are asking for.

CII 0.05 at .01 s

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 26.5475 99.2067
dIp/dt (kA/ms): 1.2717 3.1791 3.9432 6.6148
pressure (mTorr): 0.0502 0.0519 0.0508 0.0444
Bz0 (mT): 2.0653 0.3798 -1.6186 -21.1178
Br0 (mT): 1.5637 1.6137 1.8969 3.1692

Mar 31 2000 02:22:59:420PM1000331012Jim IrbyPCS repeat

IGT at 8.1e-7 at init

Plasma for 1.36 s

Reached programmed density late in shot. Something was burned off!
2Pi drops and injections stop.

John says lots of moly: "It's really up there"


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -4.5824 8.3884 23.9534 96.5898
dIp/dt (kA/ms): 1.2728 3.0508 3.5584 6.6115
pressure (mTorr): 0.0514 0.0519 0.0525 0.0459
Bz0 (mT): 2.1359 -0.4380 -1.4667 -19.5610
Br0 (mT): 1.5858 1.6276 1.7492 3.1725

Note that Bz0 is jumping +-0.4 mT. Br0 pretty stable.

H to D 1.0 at 1.0 seconds and rising
Mar 31 2000 02:32:45:670PM1000331013Jim IrbyPCS repeat

IGT 8.9e-7 Torr at init

Plasma for 1.48 s

MARFE is back

No density control again

Moly early but went away later in shot (higher density?)

Mar 31 2000 02:56:21:857PM1000331014Jim IrbyEnabled argon puff for John

Changed clearin, zxl, rcur, and rxu to start rampdown at about 1.3 s
instead of 1.5

Plasma for 1.6 s

Rampdown is much better

CII at .005 at 0.01 s

oh1: 0.2398 uohm
oh2u: 0.1331 uohm
oh2l: 0.3124 uohm

Mar 31 2000 03:14:51:577PM1000331015Jim IrbySteve wants to put less demand on EF1:

Dropped ZXU from 0.048 to 0.025
Set RXU to 0 across shot

40 kA plasma


Mar 31 2000 03:35:31:780PM1000331016Jim IrbyPCS repeat

plasma for 1.63 seconds

EF1s still railed

CII .004 at 0.01 s

Density still out of control

Jim sees a little Fe, but should not be our problem

Steve claims we were "a little double nulled"

Engineering Operator Comments
ShotTimeTypeStatusComment
108:31:06:967AMTestOktf only
210:28:16:250AMTestOkEF2U plc test only, no faults
310:43:15:263AMPlasmaOkno faults
411:07:03:500AMPlasmaOk
511:36:25:750AMPlasmaOk
611:59:35:467AMPlasmaOk
712:22:46:700PMPlasmaOk
812:44:36:810PMPlasmaBadOH2, OH1 power supply fault
901:07:12:403PMPlasmaOkno faults/no plasma
1001:22:14:530PMPlasmaOk
1101:42:47:980PMPlasmaOk
1202:03:45:310PMPlasmaOk
1302:22:57:340PMPlasmaOk
1402:45:11:827PMPlasmaOk
1503:03:51:153PMPlasmaOk
1603:24:26:090PMPlasmaOk