Alcator C-Mod Run 1000421 Information

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Miniproposals
Miniproposal:
Date Filed:
Title:
First Author:
Session Leader:Steve Wolfe (shots 1-23)

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

Engineering Operator Run Comment
machine start up

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:22:803PM
Author: To Be Determined
Session Leader's Summary for Friday, April 21, 2000 (1000421)

SL: wolfe (by default)
PO: Irby
EO: Silva/Dekow

Objectives:
. bring up RF as possible
. bring up DNB as possible
. SEG1 PG3 puff scan
. continue machine conditioning

Results:

We started with a sequence suggested by Ian during the meeting on
wall-conditioning issues, namely to investigate the effect of varying the
segment 1 gas puff on the plasma density in the absence of any other gas
puffing. This was also considered as a way of evaluating the current condition
and gas-loading of the walls. Relevant preparation included overnight ECDC in
D2, stopping approximately 2 hours before the first shot.

Shot #1 was run with a standard segment #1 gas puff and no puff after 100msec
(nl04 feedback turned off and seg#2 pg3 program zeroed). The result was a max
density nl04~6e19/m2, dropping to 1.8e19 at 1 sec and later to 1.6e19. The
shot also had a lot of runaways. The density evolution was sinilar to the
first second of Wednesday's upper null no gas shot.

Not wanting to encourage the runaway behavior, we modified the program to
include a 50msec full-on pg3 puff at 1.0 sec for subsequent shots. Shot #2 had
a larger segment 1 gas puff, reached a similar density at 0.4sec, and 1.9e19
at 1sec. It disrupted following the 1.0sec gas puff, apparently because of an
injection. It also still had significant runaway up to that point. Shot#3 was
the final shot in the sequence, with a reduced seg#1 gas puff; it ran full
length and was heavily runaway-dominated, with the hard xray monitor
saturating despite the gas puff at 1sec. The density evolution was similar to
the earlier shots, reacning a minimum of 1.8e19 at 1sec; the response to the
gas puff was up to a little over 4e19 and showed a distinct decay. This looked
extremely similar to Wednesday's upper null shot.

Tentative conclusions: The segment 1 pg3 puff has only a small effect on the
density reached in the limiter or divertor phases of these discharges, the
major player in the limiter phase (t<0.4sec) being the inner wall gas
evolution. Wednesday's low-density result was not due to runnning on the upper
null, but is reproduced in normal equilibria, indicating the effective
wall-loading is pretty low. This also means that the density increase observed
in the ohmic H-mode obtained on Wednesday occurred despite a relatively low
wall loading.

Shots #4-23 were back to a normal density program, mostly at 8e19. The purpose
was continued conditioning, and to provide a target for DNB and RF. The DNB
experienced a problem with the mod-reg, believed to be instrumentation, and
ended up punting any plasma operation for the day. The RF ran successfully
with the E-port antenna (FMIT#2), getting up to ~1.3MW in long pulses. We
observed a lot of injections coming from the antenna during the RF, some of
which tripped the RF and some of which caused terminating disruptions. The
hotspots and injections seemed to come from the Moly tiles on the side of the
antenna, not from the new BN tiles. On the last shot, j-port was also run,
getting up to 0.4MW from the half driven by FMIT#4; FMIT#3 did not run as
programmed on this shot.

Amanda also used the relatively constant shots to carry out a vertical
alignment scan of the ECE mirror. See the ECE topic in the logbook for
details.

The machine ran very well, with 100% startup reliablity for the second run in
a row, despite the (mainly rf-induced) disruptions. The frequency of
non-rf-related Mo injections is noticebly reduced from earlier in the
week. The H/D ratio was typically below 0.2 on normal density shots. Aside
from issues of antenna conditioning, we may be ready to boronize.


Physics Operator Summaries
Entered: Jul 7 2004 04:37:10:350PM
Author: To Be Determined
Physop Summary for Run 1000421

Plasma run will begin at 9:00 and end by 17:00

SL: Wolfe
PO: Irby
EO: Silva, Dekow

Engineering Setup:
------------------
ECDC should stop 1 hour before run

Power system setup as on 1000419021

Fizzle detector should be on from t=0.080 to 1.7 s
Fizzle delay on OH and TF should be as on last shot run 1000419

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
leave B-side upper as is Hybrid DISABLED
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bottom as is Hybrid DISABLED

The following gate valves should be enabled, assuming no vacuum problems:
VUV and ECE

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

Objectives:


. bring up RF as possible

. bring up DNB as possible

. SEG1 PG3 puff scan

. continue machine conditioning



Results:

The machine ran extremely well. We have now had two runs
in a row with 100% startup reliability. We were very
successful in bringing up the RF, getting the puff scan done,
and in improving the conditioning of the machine. The
DNB group managed to open their gatevalve the night before
the run, and we were hopeful they could get some shots into
plasma, but a problem with the mod/reg supply or control
killed any possibility of a beam during the run. They were also
unable to run some of the other systems because of a timing
problem. These issues will be addressed on Monday.

The RF group ran FMIT#2 into E-Port at power levels up to
1.4 MW. FMIT#4 ran into J-Port at about 400 kW. A gating
problem kept FMIT#3 off the air. Some very impressive
arcs were generated from the remaining moly protection tiles
on the upper f-side corner of the e-port antenna. A moly
tile near the antenna midplane was getting hot enough to glow
for a while on the LANL camera view (setup for visible imaging
at this time). Both of these effects may go away as we run the
antenna more and couple better to the plasma. Boronization may
also help. Note that the BN tiles seemed to be performing as
we had hoped with little or no evidence of arcing.

The first three shots of the day had factors of two to four
changes in the seg 1 puff gas 3 programming with little or
no changes in the plasma behaviour. No D2 was puffed beyond
100 ms. Note that these were large changes to the programming
not necessarily large changes to the amount of gas. The density
dropped to very low values (2e19 m^-2 NL04) by 1 second on
all three shots. These should be interesting shots for the
density control group to analyze.

The number and level of injections was much better during this
run than on the previous run. Except for the fact that we
need to condition D and J antennas during plasma operation, we
would be ready to boronize. One can also see a reduction in the
between shot carbon levels on the RGA. H-to-D ratios are improving.
Between shot mass 1 and 2 levels on the RGA are also decreasing.

Score: 23 plasma attempts and 23 plasmas

Problems:

After shot 1000421016 was completed, the self powered
CCT bypass circuit of the TF bypass cabinet generated a type 1
fault. A visual inspection of the circuit revealed no
apparent problems. The type 1 fault was clear upon
reset.

After the run we found that FMIT#2 had a problem with the
FPA bypass cap. The output cavity had to be removed and
repairs are underway.

DNB problems detailed above.

Problems were discovered with the A-side scanning probe that will
require pulling it off the machine.

----------------------------------------------------------------------------
1000421xxx irby PHYSICS_OPERATOR Apr 21 2000 8:40:11:546AM
. . . . . . . . . . . . . . . . . . . .
The DNB gatevalve was opened to the machine last night around 21:30 for the
first time.

FMIT#2 looking good into vacuum

Loaded 1000419021

Activated Segment 2, disabled Segment 4 --- TF waggle removed

Did Coldstart at 0742

Set prop gain on NL04 to zero --- no feedback

Seg 1 PG3 currently comes up from 28 to 29 ms from 0 to 80 volts
We will adjust this timing today.

Will raise TF current to 150 kA after first shot
----------------------------------------------------------------------------
1000421xxx wukitch RF Apr 21 2000 8:55:47:843AM
. . . . . . . . . . . . . . . . . . . .

FMIT #3

#3 looks like it had a tube arc at 8:50; just sitting there
spark gap fired
see fast monitor shot 4867
----------------------------------------------------------------------------
1000421xxx irby DISCHARGE_CLEAN Apr 21 2000 9:01:39:733AM
. . . . . . . . . . . . . . . . . . . .
Overnight ECDC in D2 at 2.5e-4 Torr

----------------------------------------------------------------------------
1000421001 wolfe SESSION_LEADER Apr 21 2000 9:35:28:153AM
. . . . . . . . . . . . . . . . . . . .
shot#1: First shot of Ian's segment #1 pg3 scan; seg 2 gas off, "standard" seg1 puff.

Success, sort of. It goes below 2e19, and the runaways are building up strong
after 1.2sec.

The runaways are kind of scary. I think we should put in a 50msec puff at 1.0sec and
see if it will turn them off. Most of the initial density rise is probably from the
inner wall, not the pg3 puff.

Next shot: increase the seg1 pg3 puff and add a Pitcher-puff at 1sec.
Also, increase tf to -150ka (5.4T) in seg1 and seg2.
----------------------------------------------------------------------------
1000421001 irby PHYSICS_OPERATOR Apr 21 2000 9:41:21:653AM
. . . . . . . . . . . . . . . . . . . .
Plasma --- 1.88 s


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 0.0981 -7.7070 -23.2493 -101.0968
dIp/dt (kA/ms): -0.7652 -2.6716 -3.3040 -6.9929
pressure (mTorr): 0.0728 0.0753 0.0736 0.0608
Bz0 (mT): -3.8462 -0.7289 0.9361 21.2139
Br0 (mT): -0.7850 -1.2087 -1.0259 -2.4006


----------------------------------------------------------------------------
1000421002 irby PHYSICS_OPERATOR Apr 21 2000 9:51:33:716AM
. . . . . . . . . . . . . . . . . . . .
TF now 5.4 T

Put in 50 ms, 150V gas pulse at 1.0 seconds

Increased seg 1 puff to 100 volts from 80 volts

Plasma --- disruption at 1.18 s

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 2.1472 -8.2294 -26.4112 -114.6126
dIp/dt (kA/ms): -0.7630 -3.0531 -4.3258 -6.9974
pressure (mTorr): 0.0728 0.0728 0.0744 0.0588
Bz0 (mT): -2.7456 -0.7736 1.3060 21.0065
Br0 (mT): -0.5002 -1.3321 -1.5398 -2.1928

----------------------------------------------------------------------------
1000421002 wolfe SESSION_LEADER Apr 21 2000 9:59:36:090AM
. . . . . . . . . . . . . . . . . . . .
shot#2: plasma to 1.17sec, RF fired at 1sec, and there was a Mo injection.
Ricky's camera is still not working.

next shot: shorten seg1 pg3 pulse to about half initial value. Leave
puff at 1sec, delay rf to 1.3sec
----------------------------------------------------------------------------
1000421003 irby PHYSICS_OPERATOR Apr 21 2000 10:13:39:013AM
. . . . . . . . . . . . . . . . . . . .
Reduced seg 1 gas puff: 80 volts from 28 to 40 ms, 0 volts to 100 ms

Plasma --- 1.88 s

Lots of hard X-rays after 1 seconds
----------------------------------------------------------------------------
1000421003 wolfe SESSION_LEADER Apr 21 2000 10:13:46:890AM
. . . . . . . . . . . . . . . . . . . .
shot#3: shorten seg1 pg3 pulse to about half initial value. Leave
puff at 1sec, delay rf to 1.3sec

plasma, long, lots of hards. Enough of this!

Next shot: go back to a normal shot.
----------------------------------------------------------------------------
1000421004 irby PHYSICS_OPERATOR Apr 21 2000 10:36:13:436AM
. . . . . . . . . . . . . . . . . . . .
Loaded shot 1000419002

Set Bt to 5.4 T

Density request is 8e19 NL04

Load/Clean

Plasma --- 1.89 s --- good rampdown
----------------------------------------------------------------------------
1000421004 wolfe SESSION_LEADER Apr 21 2000 10:48:06:013AM
. . . . . . . . . . . . . . . . . . . .
shot#4: go back to a normal shot. load from 1000419002 and reset tf to -150ka

Still some runaways early. This one didn't have Jim's tf back porch.
Otherwise, ok, except there is a big thrash at .45sec

No changes, except tf waveform. we'll see if the hards improve on their own.
----------------------------------------------------------------------------
1000421005 irby PHYSICS_OPERATOR Apr 21 2000 10:58:46:046AM
. . . . . . . . . . . . . . . . . . . .
Put back the 50 kA backporch on the TF

Some early x-rays but will wait another shot to fix if required - wall loading?

Plasma --- good rampdown
----------------------------------------------------------------------------
1000421005 wolfe SESSION_LEADER Apr 21 2000 10:58:48:233AM
. . . . . . . . . . . . . . . . . . . .
shot#5: plasma full length, hardly any injections.
The hards are down, and the thrash at .45 sec is much smaller.

It will perhaps be interesting to compare the gas influx on 4,5,
and subsequent shots.

Amanda is going to be doing a vertical position scan to establish
ece pointing.

Continue constant shots until further notice.
----------------------------------------------------------------------------
1000421006 wolfe SESSION_LEADER Apr 21 2000 11:20:55:390AM
. . . . . . . . . . . . . . . . . . . .
shot#6: RF is getting in about 0.4MW, not registering on RF_NET signal
shot looks pretty good, some injections.
----------------------------------------------------------------------------
1000421006 irby PHYSICS_OPERATOR Apr 21 2000 11:23:21:233AM
. . . . . . . . . . . . . . . . . . . .
Extended derivative and proportional gain on ZCUR wire 3 to 2.0 s

Enabled Argon puff for John Rice

Plasma --- 1.83 s
----------------------------------------------------------------------------
1000421007 irby PHYSICS_OPERATOR Apr 21 2000 11:37:48:966AM
. . . . . . . . . . . . . . . . . . . .
Extended Argon pulse 20 ms --- John saw nothing on last shot

Plasma --- 1.86 s

RF running well, seen on 2pi and video
----------------------------------------------------------------------------
1000421008 irby PHYSICS_OPERATOR Apr 21 2000 12:03:13:106PM
. . . . . . . . . . . . . . . . . . . .
Put in -15000 amp offset on Ip

Plasma --- 1.87 s

RF cooking
----------------------------------------------------------------------------
1000421008 wolfe SESSION_LEADER Apr 21 2000 12:04:19:746PM
. . . . . . . . . . . . . . . . . . . .
shot#8: put an offset of -15000 in the Ip predictor. The sign is probably
wrong. FSP and ASP probes will fire this shot

RF gets to 1MW (e-port)
Ip increases; got the sign right! It thinks there is zero error at 0.5sec,
which reads -792kA on the rogowski. ASP and FSP fired, Brian says they're
cleaning up.

Next shot: increase Ip offset to -23000.
----------------------------------------------------------------------------
1000421009 irby PHYSICS_OPERATOR Apr 21 2000 12:32:53:950PM
. . . . . . . . . . . . . . . . . . . .
Plasma --- > 1.8 s

RF looks good

----------------------------------------------------------------------------
1000421009 wolfe SESSION_LEADER Apr 21 2000 12:33:56:436PM
. . . . . . . . . . . . . . . . . . . .
shot#9: increase Ip offset to -23000.
RF up to 1.25MW, foil bolo is up to 1.4MW during RF.
----------------------------------------------------------------------------
1000421010 wolfe SESSION_LEADER Apr 21 2000 12:44:36:030PM
. . . . . . . . . . . . . . . . . . . .
shot#10: 1.3MW, got an injection during the RF, affects the density and current

----------------------------------------------------------------------------
1000421010 irby PHYSICS_OPERATOR Apr 21 2000 12:45:00:746PM
. . . . . . . . . . . . . . . . . . . .
No changes from 009

Plasma to 1.85 s

Something fell in: Injection in middle of RF pulse
----------------------------------------------------------------------------
1000421011 wolfe SESSION_LEADER Apr 21 2000 1:08:03:576PM
. . . . . . . . . . . . . . . . . . . .
shot#11: raise gain on Ip from 6 to 9

Big injection at .74sec, density rises.
current is better, still drooping a bit.
rf at 1.25MW, seems happy; foil bolo at 1.4MW during rf.
No apparent heating. H/D starts at ~.15, goes up during rf.
----------------------------------------------------------------------------
1000421011 irby PHYSICS_OPERATOR Apr 21 2000 1:09:15:216PM
. . . . . . . . . . . . . . . . . . . .
Raising gain on Ip from 6 to 9.

Plasma ---- > 1.8

John Rice reports lots of moly during RF pulse
----------------------------------------------------------------------------
1000421012 wolfe SESSION_LEADER Apr 21 2000 1:21:27:046PM
. . . . . . . . . . . . . . . . . . . .
shot#12: rf>1.3MW, faults half-way through.
----------------------------------------------------------------------------
1000421012 irby PHYSICS_OPERATOR Apr 21 2000 1:26:50:030PM
. . . . . . . . . . . . . . . . . . . .
No PCS changes

Plasma -- > 1.8 s
----------------------------------------------------------------------------
1000421013 irby PHYSICS_OPERATOR Apr 21 2000 1:43:40:106PM
. . . . . . . . . . . . . . . . . . . .
No changes

Plasma: 1.87 s

oh1: 0.2004 uohm
oh2u: 0.1536 uohm
oh2l: 0.3836 uohm

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -0.4242 -10.8009 -28.9827 -106.8302
dIp/dt (kA/ms): -1.1445 -2.9270 -3.9421 -6.6137
pressure (mTorr): 0.0744 0.0753 0.0744 0.0636
Bz0 (mT): -1.7266 -0.1145 1.0841 19.3209
Br0 (mT): -0.6759 -1.1107 -1.0951 -2.0770

----------------------------------------------------------------------------
1000421013 wolfe SESSION_LEADER Apr 21 2000 1:46:12:060PM
. . . . . . . . . . . . . . . . . . . .
shot#13: bp14_bc has a baseline offset. It's only 12mV, but it's there.
Big injection at 1.3s, during the rf, which started at 1sec on this shot.
----------------------------------------------------------------------------
1000421014 wolfe SESSION_LEADER Apr 21 2000 2:06:31:153PM
. . . . . . . . . . . . . . . . . . . .
shot#14: bad injection at ~0.5sec, survives. Long rf pulse at 1.1MW
bp14_bc offset is now 31mV. The jk coil is no longer on the machine,
and the gh coil has a bigger error. The DE coil looks ok, but I think
it has been flaky in the past. Wait and hope.
----------------------------------------------------------------------------
1000421014 irby PHYSICS_OPERATOR Apr 21 2000 2:17:31:093PM
. . . . . . . . . . . . . . . . .
Entered: Jul 7 2004 04:37:10:380PM
Author: To Be Determined
. .
No changes

Plasma: 1.85 s
----------------------------------------------------------------------------
1000421015 wolfe SESSION_LEADER Apr 21 2000 2:28:59:296PM
. . . . . . . . . . . . . . . . . . . .
shot#15:Injection in the middle of the rf pulse; it stays on.
rf is at ~1.2MW from 0.8 to 1.5sec
----------------------------------------------------------------------------
1000421015 irby PHYSICS_OPERATOR Apr 21 2000 2:36:14:763PM
. . . . . . . . . . . . . . . . . . . .
No changes

Plasma for > 1.8 s

oh1: 0.1575 uohm
oh2u: 0.1266 uohm
oh2l: 0.4326 uohm

See nice arc at 1.39 s on E-port antenna. Brings up
density.
----------------------------------------------------------------------------
1000421016 wolfe SESSION_LEADER Apr 21 2000 2:46:13:530PM
. . . . . . . . . . . . . . . . . . . .
shot#16: Disruption at 1.3sec, blown away by the injection from the
antenna.

bp14_bc offset is now 15mV; it's better, we'll see if the disruption
helps or hurts.
----------------------------------------------------------------------------
1000421016 irby PHYSICS_OPERATOR Apr 21 2000 2:52:43:356PM
. . . . . . . . . . . . . . . . . . . .
No changes

Plasma to 1.3 s: disruption caused by e-port

Lost TCI channels early --- gatevalve closing during shot!
----------------------------------------------------------------------------
1000421016 silva POWER_SYSTEMS Apr 21 2000 2:58:05:843PM
. . . . . . . . . . . . . . . . . . . .
After shot 1000421016 was completed, the self powered
CCT bypass circuit of the TF bypass cabinet generated a type 1
fault. A visual inspection of the circuit revealed no
apparent problems. The type 1 fault was clear upon
reset.
----------------------------------------------------------------------------
1000421017 wolfe SESSION_LEADER Apr 21 2000 3:15:30:340PM
. . . . . . . . . . . . . . . . . . . .
shot#17: rf faults at 1sec. bp14_bc offset is back down less than .01V

next shot: small tweak to nl4 program around .4:.5sec
----------------------------------------------------------------------------
1000421017 irby PHYSICS_OPERATOR Apr 21 2000 3:16:12:763PM
. . . . . . . . . . . . . . . . . . . .
Delayed Ip gain increase from 0.41 to 0.5 s. This change should
keep OHs from wildly changing near crossover

Plasma for > 1.8 s

Very little change in OHs seen
----------------------------------------------------------------------------
1000421018 wolfe SESSION_LEADER Apr 21 2000 3:26:14:530PM
. . . . . . . . . . . . . . . . . . . .
shot#18: big injection at 0.76s, disrupts at .9sec
----------------------------------------------------------------------------
1000421018 irby PHYSICS_OPERATOR Apr 21 2000 3:29:26:810PM
. . . . . . . . . . . . . . . . . . . .
Removed jag in NL04 program --- stop density drop around 400 ms near
crossover?

Plasma to 0.9 s. Big injection followed by RF did us in.
----------------------------------------------------------------------------
1000421019 irby PHYSICS_OPERATOR Apr 21 2000 3:52:29:856PM
. . . . . . . . . . . . . . . . . . . .
Removed point at about .6 seconds in PG3 programming. Should
provide a little more gas and bring up the density.

Plasma to 1.87s

Some arcing on e-port upper corner moly tile

----------------------------------------------------------------------------
1000421019 wolfe SESSION_LEADER Apr 21 2000 3:54:01:310PM
. . . . . . . . . . . . . . . . . . . .
shot#19: rf stays on, no big injections but tv shows glowing corner on e-antenna.
bp14_bc offset up to 17mV this time.
getting some early runaways.

next shot: RF requests a field ramp during rf from 5.3->5.7T
----------------------------------------------------------------------------
1000421020 wolfe SESSION_LEADER Apr 21 2000 4:10:59:356PM
. . . . . . . . . . . . . . . . . . . .
shot#20: RF requests a field ramp during rf from 5.3->5.7T
disrupts at 1.07sec
bp14_bc offset down to 13mV
----------------------------------------------------------------------------
1000421020 irby PHYSICS_OPERATOR Apr 21 2000 4:14:53:310PM
. . . . . . . . . . . . . . . . . . . .
RF has asked for a TF waggle from 1.0 to 1.3 seconds
5.4 to 5.7 and back

RF will be from 0.7 to 1.4 seconds

Plasma for about 1.1 s

TF was up to 5.7 T
----------------------------------------------------------------------------
1000421021 irby PHYSICS_OPERATOR Apr 21 2000 4:43:28:856PM
. . . . . . . . . . . . . . . . . . . .
Raised density request to 1.0e20 on NL04 at 0.65 seconds

Plasma for only 0.8 seconds

Probably raised density too late (Marmar)

----------------------------------------------------------------------------
1000421022 wolfe SESSION_LEADER Apr 21 2000 4:42:50:060PM
. . . . . . . . . . . . . . . . . . . .
shot#21: raising the density to 1.0e20
disrupts at .76, just after rf turned on.
no baseline jump on bp14_bc this time
----------------------------------------------------------------------------
1000421022 wolfe SESSION_LEADER Apr 21 2000 4:46:55:250PM
. . . . . . . . . . . . . . . . . . . .
shot#22: disrupts at 1sec

next shot: drop nl4 to 6e19
----------------------------------------------------------------------------
1000421022 irby PHYSICS_OPERATOR Apr 21 2000 4:48:21:106PM
. . . . . . . . . . . . . . . . . . . .
Raised density earlier

Plasma for 1.0 seconds
----------------------------------------------------------------------------
1000421023 irby PHYSICS_OPERATOR Apr 21 2000 5:05:55:700PM
. . . . . . . . . . . . . . . . . . . .
Dropped density to 6e19 NL04 by 0.3 seconds

Plasma for 1.9 seconds

oh1: 0.5361 uohm
oh2u: 0.1258 uohm
oh2l: 0.4486 uohm

Great Run!

Session Leader Comments
Apr 21 2000 09:35:28:153AM1000421001Steve Wolfeshot#1: First shot of Ian's segment #1 pg3 scan; seg 2 gas off, "standard" seg1 puff.

Success, sort of. It goes below 2e19, and the runaways are building up strong
after 1.2sec.

The runaways are kind of scary. I think we should put in a 50msec puff at 1.0sec and
see if it will turn them off. Most of the initial density rise is probably from the
inner wall, not the pg3 puff.

Next shot: increase the seg1 pg3 puff and add a Pitcher-puff at 1sec.
Also, increase tf to -150ka (5.4T) in seg1 and seg2.
Apr 21 2000 09:59:36:090AM1000421002Steve Wolfeshot#2: plasma to 1.17sec, RF fired at 1sec, and there was a Mo injection.
Ricky's camera is still not working.

next shot: shorten seg1 pg3 pulse to about half initial value. Leave
puff at 1sec, delay rf to 1.3sec
Apr 21 2000 10:13:46:890AM1000421003Steve Wolfeshot#3: shorten seg1 pg3 pulse to about half initial value. Leave
puff at 1sec, delay rf to 1.3sec

plasma, long, lots of hards. Enough of this!

Next shot: go back to a normal shot.
Apr 21 2000 10:48:06:013AM1000421004Steve Wolfeshot#4: go back to a normal shot. load from 1000419002 and reset tf to -150ka

Still some runaways early. This one didn't have Jim's tf back porch.
Otherwise, ok, except there is a big thrash at .45sec

No changes, except tf waveform. we'll see if the hards improve on their own.
Apr 21 2000 10:58:48:233AM1000421005Steve Wolfeshot#5: plasma full length, hardly any injections.
The hards are down, and the thrash at .45 sec is much smaller.

It will perhaps be interesting to compare the gas influx on 4,5,
and subsequent shots.

Amanda is going to be doing a vertical position scan to establish
ece pointing.

Continue constant shots until further notice.
Apr 21 2000 11:20:55:390AM1000421006Steve Wolfeshot#6: RF is getting in about 0.4MW, not registering on RF_NET signal
shot looks pretty good, some injections.
Apr 21 2000 12:04:19:747PM1000421008Steve Wolfeshot#8: put an offset of -15000 in the Ip predictor. The sign is probably
wrong. FSP and ASP probes will fire this shot

RF gets to 1MW (e-port)
Ip increases; got the sign right! It thinks there is zero error at 0.5sec,
which reads -792kA on the rogowski. ASP and FSP fired, Brian says they're
cleaning up.

Next shot: increase Ip offset to -23000.
Apr 21 2000 12:33:56:437PM1000421009Steve Wolfeshot#9: increase Ip offset to -23000.
RF up to 1.25MW, foil bolo is up to 1.4MW during RF.
Apr 21 2000 12:44:36:030PM1000421010Steve Wolfeshot#10: 1.3MW, got an injection during the RF, affects the density and current

Apr 21 2000 01:08:03:577PM1000421011Steve Wolfeshot#11: raise gain on Ip from 6 to 9

Big injection at .74sec, density rises.
current is better, still drooping a bit.
rf at 1.25MW, seems happy; foil bolo at 1.4MW during rf.
No apparent heating. H/D starts at ~.15, goes up during rf.
Apr 21 2000 01:21:27:047PM1000421012Steve Wolfeshot#12: rf>1.3MW, faults half-way through.
Apr 21 2000 01:46:12:060PM1000421013Steve Wolfeshot#13: bp14_bc has a baseline offset. It's only 12mV, but it's there.
Big injection at 1.3s, during the rf, which started at 1sec on this shot.
Apr 21 2000 02:06:31:153PM1000421014Steve Wolfeshot#14: bad injection at ~0.5sec, survives. Long rf pulse at 1.1MW
bp14_bc offset is now 31mV. The jk coil is no longer on the machine,
and the gh coil has a bigger error. The DE coil looks ok, but I think
it has been flaky in the past. Wait and hope.
Apr 21 2000 02:28:59:297PM1000421015Steve Wolfeshot#15:Injection in the middle of the rf pulse; it stays on.
rf is at ~1.2MW from 0.8 to 1.5sec
Apr 21 2000 02:46:13:530PM1000421016Steve Wolfeshot#16: Disruption at 1.3sec, blown away by the injection from the
antenna.

bp14_bc offset is now 15mV; it's better, we'll see if the disruption
helps or hurts.
Apr 21 2000 03:15:30:340PM1000421017Steve Wolfeshot#17: rf faults at 1sec. bp14_bc offset is back down less than .01V

next shot: small tweak to nl4 program around .4:.5sec
Apr 21 2000 03:26:14:530PM1000421018Steve Wolfeshot#18: big injection at 0.76s, disrupts at .9sec
Apr 21 2000 03:54:01:310PM1000421019Steve Wolfeshot#19: rf stays on, no big injections but tv shows glowing corner on e-antenna.
bp14_bc offset up to 17mV this time.
getting some early runaways.

next shot: RF requests a field ramp during rf from 5.3->5.7T
Apr 21 2000 04:10:59:357PM1000421020Steve Wolfeshot#20: RF requests a field ramp during rf from 5.3->5.7T
disrupts at 1.07sec
bp14_bc offset down to 13mV
Apr 21 2000 04:42:50:060PM1000421022Steve Wolfeshot#21: raising the density to 1.0e20
disrupts at .76, just after rf turned on.
no baseline jump on bp14_bc this time
Apr 21 2000 04:46:55:250PM1000421022Steve Wolfeshot#22: disrupts at 1sec

next shot: drop nl4 to 6e19

Physics Operator Comments
Apr 21 2000 07:27:24:780AMJim IrbyPlasma run will begin at 9:00 and end by 17:00

SL: Wolfe
PO: Irby
EO: Silva, Dekow

Goals include operation of DNB and RF

Engineering Setup:
------------------
ECDC should stop 1 hour before run

Power system setup as on 1000419021

Fizzle detector should be on from t=0.080 to 1.7 s
Fizzle delay on OH and TF should be as on last shot run 1000419

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
leave B-side upper as is Hybrid DISABLED
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bottom as is Hybrid DISABLED

The following gate valves should be enabled, assuming no vacuum problems:
VUV and ECE

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

Objectives:


. bring up RF as possible

. bring up DNB as possible

. SEG1 PG3 puff scan

. continue machine conditioning
Apr 21 2000 08:40:11:547AMJim IrbyThe DNB gatevalve was opened to the machine last night around 21:30 for the
first time.

FMIT#2 looking good into vacuum

Loaded 1000419021

Activated Segment 2, disabled Segment 4 --- TF waggle removed

Did Coldstart at 0742

Set prop gain on NL04 to zero --- no feedback

Seg 1 PG3 currently comes up from 28 to 29 ms from 0 to 80 volts
We will adjust this timing today.

Will raise TF current to 150 kA after first shot
Apr 21 2000 09:41:21:653AM1000421001Jim IrbyPlasma --- 1.88 s


Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 0.0981 -7.7070 -23.2493 -101.0968
dIp/dt (kA/ms): -0.7652 -2.6716 -3.3040 -6.9929
pressure (mTorr): 0.0728 0.0753 0.0736 0.0608
Bz0 (mT): -3.8462 -0.7289 0.9361 21.2139
Br0 (mT): -0.7850 -1.2087 -1.0259 -2.4006


Apr 21 2000 09:51:33:717AM1000421002Jim IrbyTF now 5.4 T

Put in 50 ms, 150V gas pulse at 1.0 seconds

Increased seg 1 puff to 100 volts from 80 volts

Plasma --- disruption at 1.18 s

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): 2.1472 -8.2294 -26.4112 -114.6126
dIp/dt (kA/ms): -0.7630 -3.0531 -4.3258 -6.9974
pressure (mTorr): 0.0728 0.0728 0.0744 0.0588
Bz0 (mT): -2.7456 -0.7736 1.3060 21.0065
Br0 (mT): -0.5002 -1.3321 -1.5398 -2.1928

Apr 21 2000 10:13:39:013AM1000421003Jim IrbyReduced seg 1 gas puff: 80 volts from 28 to 40 ms, 0 volts to 100 ms

Plasma --- 1.88 s

Lots of hard X-rays after 1 seconds
Apr 21 2000 10:36:13:437AM1000421004Jim IrbyLoaded shot 1000419002

Set Bt to 5.4 T

Density request is 8e19 NL04

Load/Clean

Plasma --- 1.89 s --- good rampdown
Apr 21 2000 10:58:46:047AM1000421005Jim IrbyPut back the 50 kA backporch on the TF

Some early x-rays but will wait another shot to fix if required - wall loading?

Plasma --- good rampdown




Apr 21 2000 11:23:21:233AM1000421006Jim IrbyExtended derivative and proportional gain on ZCUR wire 3 to 2.0 s

Enabled Argon puff for John Rice

Plasma --- 1.83 s




Apr 21 2000 11:37:48:967AM1000421007Jim IrbyExtended Argon pulse 20 ms --- John saw nothing on last shot

Plasma --- 1.86 s

RF running well, seen on 2pi and video
Apr 21 2000 12:03:13:107PM1000421008Jim IrbyPut in -15000 amp offset on Ip

Plasma --- 1.87 s

RF cooking
Apr 21 2000 12:32:53:950PM1000421009Jim IrbyPlasma --- > 1.8 s

RF looks good

Apr 21 2000 12:45:00:747PM1000421010Jim IrbyNo changes from 009

Plasma to 1.85 s

Something fell in: Injection in middle of RF pulse


Apr 21 2000 01:09:15:217PM1000421011Jim IrbyRaising gain on Ip from 6 to 9.

Plasma ---- > 1.8

John Rice reports lots of moly during RF pulse
Apr 21 2000 01:26:50:030PM1000421012Jim IrbyNo PCS changes

Plasma -- > 1.8 s


Apr 21 2000 01:43:40:107PM1000421013Jim IrbyNo changes

Plasma: 1.87 s

oh1: 0.2004 uohm
oh2u: 0.1536 uohm
oh2l: 0.3836 uohm

Time (ms): 0 5 10 25
----------------------------------------
Ip (kA): -0.4242 -10.8009 -28.9827 -106.8302
dIp/dt (kA/ms): -1.1445 -2.9270 -3.9421 -6.6137
pressure (mTorr): 0.0744 0.0753 0.0744 0.0636
Bz0 (mT): -1.7266 -0.1145 1.0841 19.3209
Br0 (mT): -0.6759 -1.1107 -1.0951 -2.0770

Apr 21 2000 02:17:31:093PM1000421014Jim IrbyNo changes

Plasma: 1.85 s

Apr 21 2000 02:36:14:763PM1000421015Jim IrbyNo changes

Plasma for > 1.8 s

oh1: 0.1575 uohm
oh2u: 0.1266 uohm
oh2l: 0.4326 uohm

See nice arc at 1.39 s on E-port antenna. Brings up
density.
Apr 21 2000 02:52:43:357PM1000421016Jim IrbyNo changes

Plasma to 1.3 s: disruption caused by e-port

Lost TCI channels early --- gatevalve closing during shot!


Apr 21 2000 03:16:12:763PM1000421017Jim IrbyDelayed Ip gain increase from 0.41 to 0.5 s. This change should
keep OHs from wildly changing near crossover

Plasma for > 1.8 s

Very little change in OHs seen


Apr 21 2000 03:29:26:810PM1000421018Jim IrbyRemoved jag in NL04 program --- stop density drop around 400 ms near
crossover?

Plasma to 0.9 s. Big injection followed by RF did us in.


Apr 21 2000 03:52:29:857PM1000421019Jim IrbyRemoved point at about .6 seconds in PG3 programming. Should
provide a little more gas and bring up the density.

Plasma to 1.87s

Some arcing on e-port upper corner moly tile

Apr 21 2000 04:14:53:310PM1000421020Jim IrbyRF has asked for a TF waggle from 1.0 to 1.3 seconds
5.4 to 5.7 and back

RF will be from 0.7 to 1.4 seconds

Plasma for about 1.1 s

TF was up to 5.7 T
Apr 21 2000 04:43:28:857PM1000421021Jim IrbyRaised density request to 1.0e20 on NL04 at 0.65 seconds

Plasma for only 0.8 seconds

Probably raised density too late (Marmar)

Apr 21 2000 04:48:21:107PM1000421022Jim IrbyRaised density earlier

Plasma for 1.0 seconds

Apr 21 2000 05:05:55:700PM1000421023Jim IrbyDropped density to 6e19 NL04 by 0.3 seconds

Plasma for 1.9 seconds

oh1: 0.5361 uohm
oh2u: 0.1258 uohm
oh2l: 0.4486 uohm

Great Run!

Engineering Operator Comments
ShotTimeTypeStatusComment
109:16:13:593AMPlasmaOkno faults/plasma
209:42:48:373AMPlasmaOkno faults/plasma
310:07:16:903AMPlasmaOk
410:29:06:200AMPlasmaOk
510:50:28:200AMPlasmaOk
611:14:22:200AMPlasmaOk
711:34:19:513AMPlasmaOk
811:54:44:640AMPlasmaOk
912:15:49:390PMPlasmaOk
1012:36:05:700PMPlasmaOk
1112:56:14:543PMPlasmaOk
1201:16:16:780PMPlasmaOk
1301:36:26:920PMPlasmaOk
1401:56:45:903PMPlasmaOk
1502:18:55:217PMPlasmaOk
1602:37:33:670PMPlasmaOk
1703:01:03:200PMPlasmaOk
1803:21:07:530PMPlasmaOk
1903:40:48:390PMPlasmaOk
2004:03:23:390PMPlasmaOk
2104:22:33:047PMPlasmaOk
2204:41:18:297PMPlasmaOk
2305:00:23:983PMPlasmaOk