Alcator C-Mod Run 941208 Information

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Miniproposals
Miniproposal:052
Date Filed: 4/12/1994
Title:ICRF Antenna Tuning (P
First Author:Yuichi Takase
Session Leader:Yuichi Takase (shots 1-28)
Miniproposal:054
Date Filed: 4/5/1994
Title:ICRF Antenna Conditioning (PRF> 100kW)
First Author:Yuichi Takase
Session Leader:John Goetz (shots 1-28)

Operators
Session leader(s):Yuichi Takase,John Goetz
Physics operator(s):John Goetz
Engineering operator(s):Joe Daigle,Vinny Bertolino

Engineering Operator Run Comment
icrf tuning

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:11:493PM
Author: To Be Determined
Session Leader's Summary for 941208
SL: Takase
PO: Goetz
EO: Daigle

MP052A ICRF Tuning
MP054A ICRF Conditioning

1st RF run of Phase II-B (D-port antenna only).
Start from 941206024 (Inner-wall limited, up-down symmetric).
Objective: Establish tune, then bring up power (constant shots).

We have achieved more than we anticipated, thanks to previous experience
and piggy-backing on yesterday's run:

Acceptable tuning was achieved on shot 003.
RF power was brought up to approximately 1.8MW.

In addition:

A high triangularity limiter plasma was developed (for example, 941208026).
CX now sees H signals correlated with H puffs.
Started developing a diverted plasma with better match to the antenna.

Technical problems:

\RF_POWER_NET should not be trusted for shots 010-025.
RF CAMAC had noise and malfunction problems at high RF power levels.
HIREX sees more RF pick-up than last year.

Shot
001 fizzle
002 plasma 820kA nel_05=0.85 oright=3->3.5cm working on tuning
003 plasma nel_05=0.85 oright=1.5->2.3cm good tune
004 fizzle
005 plasma nel_05=0.85->0.80 P_rf=30kW good tune
006 fizzle
007 fizzle P_rf=3kW at breakdown
008 plasma P_rf=70kW, nel still dropping, oright stable at 2cm
009 plasma P_rf=270kW, R_L constant after 0.5sec
010 plasma P_rf=320kW (\RF_POWER_NET starting to saturate)
011 plasma P_rf=800kW
012 plasma P_rf>1MW (something happened on the antenna? or noise?)
013 plasma P_rf=800kW
014 plasma P_rf=900kW
015 plasma P_rf=1.0MW
016 plasma P_rf=1.0MW (attenuators back in, but CAMAC problem)
017 plasma P_rf=1.2MW (still have CAMAC problem)
018 plasma P_rf=1.4MW (power meas. fixed, but have noise problem)
019 plasma P_rf=1.5MW (CAMAC problem)
020 plasma P_rf=1.5MW (CAMAC problem)
021 plasma P_rf=1.6MW (CAMAC problem)
022 plasma P_rf=1.6MW (CAMAC problem)
023 plasma P_rf=1.7MW (CAMAC problem)
024 plasma P_rf=1.8MW (CAMAC problem), nel_05=1.0
025 plasma P_rf=1.7MW (CAMAC problem), nel_05=0.95, H 100V X .2s @ .3s
026 plasma P_rf=1.6MW (CAMAC worked!), nel_05=0.95, H 100V X .4s @ .3s
027 plasma P_rf=1.4MW Diverted (H-mode), nel_05=0.95, no H puff
028 plasma disrupted @ .44s

Physics Operator Summaries
Entered: Jul 7 2004 04:36:52:427PM
Author: To Be Determined
Physics operator summary for 941208

EO: Bertilino/Daigle
PO: Goetz
SL: Takase

Run 941208 was in support of Mini-Proposal #052A - ICRF Tuning.
This proposal calls for a load for the RF antenna at D-Port. To this end,
shot 941206024 was loaded into the hybrid. This was a limiter discharge
that had an acceptable equilbrium.

Today's goal was to try to obtain shots suitable as a load for
the antenna.

This goal was accomplished and then some. The RF cabal obtained plasmas
suitable for loading studies and moved on to conditioning. A maximum of 1.7MW
was put in the plasma. Reproducible shots were obtained. The first 26 shots
were limited shots with successively higher triangularity (as requested by
the session leader). The last two shots were divertor discharges.

Some things discovered today:
1) The beginning of the run was beset with fizzles. This may have been
the result of no ECDC before the run. It turns out that the current
was rising too quickly. This was solved by some combination of
higher fill pressure and more gain on the RCUR wire in segment 1.
2) Limiter plasmas with triangularity <=0.5 were obtained. See shots up
to 941208026 for examples. This was accomplished with CLEARIN, ZXU,
ZXL, RXU, and RXL programming.
2) Be wary of asking for an unworkable combination of RCUR and CLEARIN,
given the EF2 current limit (see shot 941208028 for example).


Engineering today: Reliable day today for the power systems. PCS did not
load the V's when IMPORT_SEGMENT was used. Josh fixed this bug.

Scorecard: 28 shots = 24 plasmas + 4 fizzles

Shot summary for Run 941208

Reload of 941206024

Changes to shot 941206024:
NL_07=8.0e19
fizzle detector off at 1.5sec
add I gain to CLEARIN =02.5 at 0.05sec
RCUR offset = 10000. in segment 2 & change drawn waveform by
10000/800000 & remove notch in D gain

Shot change result
____ _____ ______
1 P_0 = 1.5e-5 fizzle - fields look o.k.

2 P_0 = 1.3e-5 plasma - disr. at 1.17
outer gap = 3.5cm
EF2's on the rail

3 RCUR = .657 in segment 2 plasma - disr. at 1.13
EF2's off the rail
outer gap=2->2.3cm; kappa=1.45

4 slow down Ip ramp down fizzle - moves out and hits @
less delta RCUR during ramp-down .017sec
slide PG3 -.003sec

5 no changes plasma - 0.83MA - disr @ 1.43
outer gap 2->2.3cm

6 PG1 @ 0.3 (90V x .02sec) fizzle - hits at .02sec
less delta RCUR during ramp-down
ramp up programmed density
ramp RCUR to .659 @ 1.0sec

7 lower RCUR D gain to 2 @ .02sec fizzle - hits at .018sec

8 RCUR=.66 in segment 1 plasma - .83MA
RCUR D gain to 4 @ .02sec outer gap 1.9->2.0cm
P_0 = 1.4e-5 density falling; loading falling

9 ramp density to .925e20 plasma - .83MA - inversion time
P_0=1.5e-5 .25MW RF; outer gap 1.95cm
RCUR P=6 and D=5 @ .015 density stays up

10 RXU & RXL = -.017 for more triang. plasma - .83MA - invert time
no change in triangularity

11 RXL & RXU = -.019 plasma - .83MA
ZXL=-.018 & ZXU=.023 RF in ~ 0.6MW
delta Te ~ 0.3keV

12 widen PG1 to .023sec plasma - .83MA
P gain on RXL & RXU = 5 RF ~ 1.0MW; delta Te ~ 0.5keV
no change in triangularity

13 RXL & RXU = -.022 plasma - .83MA
RF~0.8MW; delta Te ~ 0.3keV

14 CLEARIN=-.04 plasma - .83MA
RF~1.2MW; delta Te~0.5keV

15 CLEARIN=-.035 & ZXU=-.025 plasma - .83MA
RF~1.3MW; delta Te~0.5keV
triangularity = 0.4

16 ZXL=-.025 & ZXU=.03 plasma - .84MA
RF~1.0MW; delta Te~0.6keV
triang=.4 - kappa=1.6

17 RXL=-.025 & RXU=-.030 plasma - .83MA
RF~1.2MW; delta Te~0.6keV

18 no changes plasma - .83 MA
RF~1.4MW; delta Te~0.7keV

19 no changes plasma - .83MA
RF~1.4MW; delta Te~.75keV

20 no changes plasma - .83MA
RF~1.5MW; delta Te~0.8keV

21 RXU=-.035 plasma - .83MA
RF~1.5MW; delta Te~0.7keV
upper_tri=0.5 lower_tri=0.4

22 no changes plasma - .83MA
RF~1.7MW; delta Te~0.7keV

23 no changes plasma - .83MA
RF~1.6MW; delta Te~0.8keV

24 nel_04=1.05e20 plasma - .83MA
RF trips on high refl. power

25 nel_04=.925e20 plasma - .83MA
PG2=(100Vx.02) @ 0.3sec RF~1.7MW; delta Te~.75keV

26 PG2=(100V x .04sec) @ 0.3sec plasma - .83MA
RF~1.7MW; delta Te~.7keV

27 loaded seg 2 from 941206025 into plasma - .83MA - diverted
segment 2 (PCS bug - didn't load RF~1.5MW; delta Te~0.5keV
the V's; Josh fixed) loading reduced
nel_04=.925e20; RCUR=.652; slow Ip ramp

28 RCUR=0.64 until 0.4sec (was on limiter) plasma - disrupts @ 0.43
RCUR=.652 from 0.5sec on too much delta_RCUR for CLEARIN

Session Leader Comments
Dec 8 1994 08:59:38:880AM941208001Yuichi Takase1st RF run of Phase II-B
Start from 941206024 (Inner-wall limited, up-down symmetric).
D-port antenna only.
Establish tune, then bring up power (constant shots).

Shot 001: fizzle

Dec 8 1994 09:41:52:050AM941208002Yuichi TakaseShot 002
Plasma 820kA nel_05=0.85 oright=3->3.5cm
working on tuning
move plasma out for next shot (want oright=2cm)

Dec 8 1994 09:44:20:400AM941208003Yuichi TakaseShot 003
Plasma nel_05=0.85 oright=1.5->2.3cm
good tune

Dec 8 1994 09:48:34:060AM941208004Yuichi TakaseShot 004
Fizzle
Will be increasing RF power for the next few shots.

Dec 8 1994 10:14:57:610AM941208005Yuichi TakaseShot 005
Plasma
Bringing the RF power up.
P_rf=30kW

Dec 8 1994 10:23:17:980AM941208006Yuichi TakaseShot 006
Fizzle

Dec 8 1994 10:43:03:990AM941208007Yuichi TakaseShot 007
Fizzle
RF at breakdown (3kW)

Dec 8 1994 11:13:16:210AM941208008Yuichi TakaseShot 008
Plasma
Density still dropping, oright stable at 2cm
P_rf=70kW

Dec 8 1994 11:25:32:470AM941208009Yuichi TakaseShot 009
Plasma
P_rf=270kW, R_L constant after 0.5sec

Dec 8 1994 11:50:26:630AM941208010Yuichi TakaseShot 010
Plasma
P_rf=320kW
Beware: \RF_POWER_NET not correct beyond this power (today only)

Dec 8 1994 12:21:32:770PM941208011Yuichi TakaseShot 011
Plasma
P_rf=800kW

Dec 8 1994 12:23:01:340PM941208012Yuichi TakaseShot 012
Plasma
P_rf>1MW (don't have reliable power meas.)
Something happened on the antenna, or have noise problem

Dec 8 1994 12:24:10:500PM941208013Yuichi TakaseShot 013
Plasma
P_rf=.8MW

Dec 8 1994 12:50:22:090PM941208014Yuichi TakaseShot 014
Plasma
P_rf=.9MW

Dec 8 1994 12:59:03:680PM941208015Yuichi TakaseShot 015
Plasma
P_rf=1.0MW

Dec 8 1994 01:39:31:070PM941208016Yuichi TakaseShot 016
Plasma
Power measurement fixed (put attenuators back in).
But have CAMAC problem.
P_rf=1.0MW

Dec 8 1994 02:00:53:710PM941208017Yuichi TakaseShot 017
Plasma
Still have CAMAC problem.
P_rf=1.2MW

Dec 8 1994 02:09:01:310PM941208018Yuichi TakaseShot 018
Plasma
P_rf=1.4MW (power meas. fixed, but have noise problem)

Dec 8 1994 03:06:16:620PM941208019Yuichi TakaseShot 019
Plasma
P_rf=1.5MW (CAMAC problem)

Dec 8 1994 03:06:51:170PM941208020Yuichi TakaseShot 020
Plasma
P_rf=1.5MW (CAMAC problem)

Dec 8 1994 03:07:50:710PM941208021Yuichi TakaseShot 021
Plasma
P_rf=1.6MW (CAMAC problem)

Dec 8 1994 03:11:34:830PM941208022Yuichi TakaseShot 022
Plasma
P_rf=1.6MW (CAMAC problem)

Dec 8 1994 03:38:27:460PM941208023Yuichi TakaseShot 023
Plasma
P_rf=1.7MW (CAMAC problem)

Dec 8 1994 04:08:55:980PM941208024Yuichi TakaseShot 024
Plasma
A little higher density, nel_05=1.0
P_rf=1.8MW (CAMAC problem)

Dec 8 1994 04:13:51:280PM941208025Yuichi TakaseShot 025
Plasma
nel_05=0.9, H 100V X .2s @ .3s
P_rf=1.7MW (CAMAC problem)

Dec 8 1994 04:41:42:660PM941208026Yuichi TakaseShot 026
Plasma
nel_05=0.95, H 100V X .4s @ .3s
P_rf=1.6MW (CAMAC worked)

Dec 8 1994 04:56:09:940PM941208027Yuichi TakaseShot 027
Plasma, Diverted, H-mode
nel_05=0.95, no H puff
P_rf=1.4MW (CAMAC worked), R_L=4.5Ohm

Dec 8 1994 05:16:57:330PM941208028Yuichi TakaseShot 028
Plasma, Diverted, disrupted @ 0.44s

Physics Operator Comments
Dec 8 1994 08:20:26:010AMJohn GoetzRun 941208

In support of Mini-Proposal #052A - ICRF Tuning

The objectives of this proposal are too just get plasmas
to be the load for the RF antenna at D-port.

Start from Shot 941206024 - a limiter discharge
Changes: Nel_04=0.8e20
RCUR offset = 10000 in segment 2 and change the
drawn waveform by 10000/800000 and remove the
notch in the D gain
fizzle detector off at 1.5sec
I gain on CLEARIN = 0.25 @ .05sec

Hybrid initialization - all matrices respond.

Dec 8 1994 09:03:38:580AM941208001John GoetzShot 941208001
Fizzle - fields looked o.k.

For shot 941208002:
P_0 = 1.3e-5

Dec 8 1994 09:21:41:320AM941208002John GoetzShot 941208002
Plasma - disruption @ 1.17sec
outer gap = 3.5cm
EF2's on the rail - leads to the loss of vertical position

For shot 941208003:
RCUR = 0.657 in segment 2 (close outer gap)
CLEARIN = -.045 (to help EF2's)

Dec 8 1994 09:42:11:640AM941208003John GoetzShot 941208003
Plasma - disruption @ 1.13sec
outer gap = 2 -> 2.3cm
kappa = 1.45
EF2's off the rail

For shot 941208004:
slide PG3 -.003sec
slow down Ip rampdown
don't pull the plasma in as far during rampdown

Dec 8 1994 09:53:31:360AM941208004John GoetzShot 941208004
Fizzle - plasma moves out and hits at .017

For shot 941208005:
no changes

Dec 8 1994 10:14:42:650AM941208005John GoetzShot 941208005
Plasma - 0.83MA - disr @ 1.43sec
outer gap = 2.0->2.3cm

For shot 941208006:
ramp up programmed density
enable B_SIDE_LOWER - PG1 puff at 0.3 (90V x .02sec)
less delta RCUR during ramp-down
ramp RCUR to .659 at 1.0 sec to hold outer gap constant

Dec 8 1994 10:28:34:860AM941208006John GoetzShot 941208006
Fizzle - moves out and hits at .02sec

For shot 941208007:
lower RCUR D gain to 2 at 0.02sec

Dec 8 1994 10:42:28:670AM941208007John GoetzShot 941208007
Fizzle - moves out and hits at .018sec
current is rising quickly

For shot 941208008:
raise RCUR D gain to 4 at 0.02sec
RCUR drawn waveform = .66 in segment 1
P_0 = 1.4e-5

Dec 8 1994 11:07:16:750AM941208008John GoetzShot 941208008
Plasma - 0.83MA
moves out more slowly during startup than 007
outer gap 1.9->2.0cm
density falling - loading drops

For shot 941208009:
raise RCUR P gain to 6 @ .015 sec
raise RCUR D gain to 5 at 0.015sec
RCUR drawn waveform = .65 in segment 1
P_0 = 1.5e-5
ramp up density waveform to .925e20

Dec 8 1994 11:25:25:000AM941208009John GoetzShot 941208009
Plasma - 0.83MA
moves out more slowly during startup than 008 ( and 007)
outer gap 1.9->2.0cm
density better
0.25MW injected RF

For shot 941208010:
RXL & RXU = -.017 (were -.015) to raise triangularity

Dec 8 1994 11:43:29:050AM941208010John GoetzShot 941208010
Plasma - 0.83MA
outer gap 1.9->2.1cm
no change in triangularity
0.32MW injected RF

For shot 941208011:
RXL & RXU =-.019; ZXU=.023; ZXL=-.018 to increase triangularity

Dec 8 1994 12:15:13:170PM941208011John GoetzShot 941208011
Plasma - 0.83MA
outer gap 1.9cm
no change in triangularity
0.6MW injected RF - shows up on many traces

For shot 941208012:
widen PG1 to .023sec
P gain on RXL & RXU = 5 (was 3)

Dec 8 1994 12:16:22:710PM941208012John GoetzShot 941208012
Plasma - 0.83MA
outer gap 1.9cm
no change in triangularity
1.0MW injected RF - shows up on many traces
delta Te ~ 0.5keV

For shot 941208013:
RXL & RXU = -.022

Dec 8 1994 12:35:16:910PM941208013John GoetzShot 941208013
Plasma - 0.83MA
outer gap 1.9->2.1cm
no change in triangularity
0.8MW injected RF - delta Te ~ 0.3keV

For shot 941208014:
CLEARIN=-.04 (to change triangularity)

Dec 8 1994 12:49:09:270PM941208014John GoetzShot 941208014
Plasma - 0.83MA
outer gap 2.0cm
triangularity increases to 0.4
1.2MW injected RF - delta Te ~ 0.5keV

For shot 941208015:
CLEARIN=-.035 and ZXU=-.025 (to change triangularity)

Dec 8 1994 01:17:22:260PM941208015John GoetzShot 941208015
Plasma - 0.83MA
outer gap 1.9->2.0cm
triangularity = 0.4
1.3MW injected RF - delta Te ~ 0.5keV

For shot 941208016:
ZXL=-.025 & ZXU=+.03 (for triangularity)

Dec 8 1994 01:38:51:280PM941208016John GoetzShot 941208016
Plasma - 0.83MA
outer gap 1.9->2.0cm
triangularity = 0.4 - kappa = 1.6
1.0MW injected RF - delta Te ~ 0.6keV

For shot 941208017:
RXL=-.025 & RXU=-.03 (for triangularity)

Dec 8 1994 01:56:21:340PM941208017John GoetzShot 941208017
Plasma - 0.83MA
1.2MW injected RF - delta Te ~ 0.6keV
EFIT didn't run - no delta nor kappa to report

For shot 941208018:
no changes

Dec 8 1994 02:16:12:250PM941208018John GoetzShot 941208018
Plasma - 0.83MA
1.4MW injected RF - delta Te ~ 0.7keV
triang=0.5->0.4; kappa=1.6

For shot 941208019:
no changes

Dec 8 1994 02:30:27:220PM941208019John GoetzShot 941208019
Plasma - 0.83MA
1.4MW injected RF - delta Te ~ 0.75keV
triang=0.5->0.4; kappa=1.6; outer gap =2.0cm

For shot 941208020:
no changes

Dec 8 1994 02:45:05:160PM941208020John GoetzShot 941208020
Plasma - 0.83MA
1.5MW injected RF - delta Te ~ 0.8keV
triang=0.5->0.4; kappa=1.6; outer gap =2.0cm

For shot 941208021:
RXU=-.035

Dec 8 1994 03:02:50:640PM941208021John GoetzShot 941208021
Plasma - 0.83MA
1.5MW injected RF - delta Te ~ 0.7keV
triang=0.5(upper)->0.4(lower); kappa=1.6; outer gap =2.0cm

For shot 941208022:
no changes

Dec 8 1994 03:19:11:240PM941208022John GoetzShot 941208022
Plasma - 0.83MA
1.7MW injected RF - delta Te ~ 0.7keV
triang=0.5(upper)->0.4(lower); kappa=1.6; outer gap =2.0cm

For shot 941208023:
no changes

Dec 8 1994 03:40:09:220PM941208023John GoetzShot 941208023
Plasma - 0.83MA
1.6MW injected RF - delta Te ~ 0.8keV
triang=0.5(upper)->0.4(lower); kappa=1.6; outer gap =2.0cm

For shot 941208024:
nel_04=1.05e20

Dec 8 1994 03:59:21:590PM941208024John GoetzShot 941208024
Plasma - 0.83MA
RF trips on high reflected power
nel_04=1e20

For shot 941208025:
nel_04=.925e20
enable B_SIDE_UPPER
PG2 @ 0.3sec (100V x .02sec)

Dec 8 1994 04:14:08:950PM941208025John GoetzShot 941208025
Plasma - 0.83MA
RF~1.7MW; delta Te~0.75keV

For 941208026:
no changes

Dec 8 1994 04:40:01:770PM941208026John GoetzShot 941208026
Plasma - 0.83MA
RF~1.7MW; delta Te~0.7keV

For 941208027:
loaded segment 2 from 941206025 into segment 2 (a diverted shot)
set RCUR = .652
Ip rampdown slowed
nel_04=.925e20

Dec 8 1994 04:57:59:540PM941208027John GoetzShot 941208027
Plasma - 0.83MA (diverted)
RF~1.5MW; delta Te~0.5keV; loading reduced
outer gap ~ 2.0cm

For 941208028:
RCUR=.654cm (shrink outer gap)
RCUR=.64cm until 0.4sec (was touching limiter)

Dec 8 1994 05:41:11:660PM941208028John GoetzShot 941208028
Plasma - disrupts @ 0.43sec
vertical instability
asked for too much delta_RCUR for the given CLEARIN

Engineering Operator Comments
ShotTimeTypeStatusComment
108:50:28:990AMPlasmaOkno faults
209:02:43:180AMPlasmaOkdisruption induced comm faults on oh1 and oh2l
309:20:00:390AMPlasmaOkdisruption induced comm faults, oh1 and oh2l
409:42:50:980AMPlasmaOkno faults
509:55:05:680AMPlasmaOkdisruption induced comm faults, oh1, oh2l and ef1u
610:14:23:370AMPlasmaOkno faults
710:28:51:500AMPlasmaOkno faults
810:43:16:940AMPlasmaOkno faults
911:09:49:410AMPlasmaOkno faults
1011:25:23:220AMPlasmaOkno faults
1111:43:32:000AMPlasmaOkno faults
1212:01:01:640PMPlasmaOkno faults
1312:17:22:110PMPlasmaOkno faults
1412:32:36:300PMPlasmaOkno faults
1512:49:49:170PMPlasmaOkno faults
1601:23:15:550PMPlasmaOkNo Faults.
1701:40:27:880PMPlasmaOkNo Faults
1801:56:57:290PMPlasmaOkNo Faults.
1902:15:54:460PMPlasmaOkNo faults.
2002:30:41:430PMPlasmaOkNo faults.
2102:47:33:110PMPlasmaOkNo faults
2203:04:27:030PMPlasmaOkNo faults.
2303:22:30:000PMPlasmaOkNo Faults.
2403:43:25:360PMPlasmaOkNo Faults.
2504:00:33:660PMPlasmaOkNo faults.
2604:20:01:620PMPlasmaOkNO Faults.
2704:41:28:200PMPlasmaOkno faults
2804:58:42:660PMPlasmaOkNo Faults