Alcator C-Mod Run 1060526 Information

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Miniproposals
Miniproposal:404a
Date Filed: 1/31/2005
Title:Parametric Dependence of Moderate n Alfvén Eigenmode Damping Rates
First Author:Joseph Snipes
Session Leader:Joseph Snipes (shots 19-35)
Miniproposal:415
Date Filed: 2/24/2005
Title:Rotation and H-mode Power Threshold for LSN and USN at Different IP and ne
First Author:John Rice
Session Leader:John Rice (shots 1-18)

Operators
Session leader(s):John Rice,Joseph Snipes
Physics operator(s):Steve Wolfe
Engineering operator(s):Andy Pfeiffer,Bill Byford,Ed Fitzgerald

Engineering Operator Run Comment
MP#415 Rotation and H-mode threshold and possibly MP#404a Alfven damping

Session Leader Plans
Entered: May 25 2006 02:23:27:030PM
Author: John Rice
1.) Revisit USN H-mode discharge:

Start with 1060523013. enable B-side lower, with 1 PSI Ar and 2 PSI Ne.
ICRF 1.0 MW, 0.7 - 1.2 s.

once this discharge is established, recheck H-mode power threshold by increasing/
decreasing incrementally by 100 kW.

no DNB unless noise problem is fixed

once H-mode power threshold is determined,

2.) Load LSN discharge 1060524012:

ICRF 3.0 MW, 0.7 - 1.2 s.

once this discharge is established, recheck H-mode power threshold by increasing/
decreasing incrementally by 200 kW.

3.) if time allows, repeat above at 1.0 MA
Entered: May 25 2006 03:34:39:017PM
Author: Joseph Snipes
Run Plan for MP#404a TAE Damping with ICRF

Begin with 1060309020 inner wall limited moderate elongation plasmas with
nl04 = 9 x 10^19 m^-2, Ip = 0.8 MA, and BT = 5.4 T. Reduce nl04 to 7 x 10^19 m^-2.
Sweep the active MHD antennas through the calculated center of the gap TAE frequency
multiple times throughout the discharge and look for resonances. From shot to shot
slowly increase the ICRF power in steps of 0.25 MW from 0.5 to 1.5 s up
to 2.5 MW or until unstable TAEs are observed. Measure the TAE damping
rate for each ICRF power level.

Physics Operators Plans
Entered: May 25 2006 03:42:08:017PM
Author: Steve Wolfe
Engineering setup and Physop run plan for Friday 1060526
MP#415 Rotation and H-mode threshold (reverse field)
    and possibly 
MP#404a Alfven damping measurements (Reverse field)
SL: MP#415 -  Rice
    MP#404a - Snipes
PO: wolfe

Overnight ECDC in D2, bake at 60C
Run starts at 09:00 (lockup at 8:30) ends at 17:00

Power system as on 1060523013
 Acoil [-Dtop +Dbot +Jtop -Jbot]
Gas setup:
 fill B-Top with 6 psi D2 Hybrid enabled (PG4)
 fill B-side lower with 1 psi Ar + 2 psi Ne Hybrid DISABLED (PG1)
 leave B-side upper as is Hybrid DISABLED (PG2)
 fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3)
 leave NINJA as is DISABLED
Enable the following gate valves and shutters, assuming no vacuum problems:
ECE, VUV, Z-bolo shutters. DO NOT ENABLE DNB until authorized by Physop.

TORVAC: Gate valves open

FMIT#1,2,3,4 in RUN-ON by 08:30

Physop plan:
-------------
 Start from USN 1060523013 (segment 3)
 Load 1060524012 seg2 into seg2.
 enable dpcs_ftae2 if AMHD system is going to be ready.
 Import Joe's shot 1060309020 into seg4 and 
 flip waveforms and recalculate predictors. 
 
AMHD can troubleshoot and piggyback during MP#415 shots
MP#415 shots:
 Start from the USN case in seg3
 Let RF tweak power to find threshold

 Change to LSN as in 1060524012 (import to seg2)
 Find threshold

If there is time, increase current to 1MA and repeat for LSN and USN
 
If AMHD is working, go to MP#404a:
 Begin with 1060309020 inner wall limited moderate elongation plasmas with
 nl04 = 9 x 1019 m^-2, Ip = 0.8 MA, and BT = 5.4 T.  
 Reduce nl04 to 7 x 1019 m^-2.
 Sweep the active MHD antennas through the calculated center of the gap TAE   
 frequency multiple times throughout the discharge and look for resonances.  
 From shot to shot slowly increase the ICRF power in steps of 0.25 MW from 
  0.5 to 1.5 s up to 2.5 MW or until unstable TAEs are observed.  
 Measure the TAE damping rate for each ICRF power level.  

 



Session Leader Summaries
Entered: May 26 2006 01:47:41:290PM
Author: John Rice
The first half of the run was dedicated to MP 415, H-mode power threshold in USN and LSN with
reversed plasma current. Shots 1-9 were USN and the power threshold was found to be near 1.6 MW
ICRF, with a total input power of 2.2 MW. It appears that that strong neon puffing increases
the power threshold. Shots 10-18 were with LSN, and the ICRF power threshold was near 3.4 MW.
At slightly lower power, the plasma seemed to be in Super L-mode, with a substantial increase
in the electron density (due to the RF) but not actually H-mode. Lowering the target density
allowed access to H-mode. These power thresholds were similar were similar to those previously
determined with normal plasma current, but LSN and USN switched.
Entered: May 26 2006 05:24:24:460PM
Author: Joseph Snipes
For a half run day with a lot of fizzles, we still managed to get some interesting results out of the damping
rate measurement with increasing ICRF power. We have good data for 0, 0.5, 1.5, 2.0, and 2.5 MW which appear
to show that the damping rate increases with increasing RF power, which is exactly opposite to the results
on JET for n=1 modes. We still need to determine what are the n numbers for these resonances though.
The changes Willy Burke made to the active MHD amplifier controller worked pretty well and allowed more
resonances to be found. There were still a number of glitches in the amplifier current, but they were much
less frequent than before. Surprisingly, the active MHD current seemed to be smoother with increasing RF power!
Damping rates started out in the 4 to 5 percent range, but with increasing RF power reached 14 percent. Then,
at 2.5 MW, the damping rates decreased again to 3 to 4 percent. We did not try going to 3 MW because the
RF was already beginning to fault at 2.5 MW and was not believed would be reliable at 3 MW. So, we returned
to zero RF power to get a baseline damping rate without fast ions. The CNPA got good data as well, so we
should be able to get an idea of the tail temperatures for most of these shots. More analysis is required
to check over the results carefully to be sure they are consistent for different shots.
The first half of the day compared USN and LSN plasmas and we have some active MHD data during the
Ohmic phases of those discharges, but during the ICRF phases, the 500 kHz beat wave between the D and E
antennas makes it difficult to measure damping rates with a sweep through the beat frequency.
Initial comparison of USN and LSN did not give a clear trend of the damping with the ion grad B drift
direction. More analysis is required to select a particular toroidal mode number if possible.

Physics Operator Summaries
Entered: May 26 2006 06:08:34:880PM
Author: Steve Wolfe
Phys Op Summary for Friday, 1060526
MP#415 (SL Rice)
MP#404a (SL Snipes)
PO: wolfe

The run started off well and we pretty much completed
the upper and lower null threshold run by 1:30PM. The 
Alfven wave damping experiment was hampered by multiple
fizzles, but they did complete an RF power scan. 

MP#415 began with upper null plasmas (800kA, 5.4T) except 
that I forgot to drop the segment 1 field back to 5.4 from
the 5.9T startup that was being used yesterday. By the
time the RF came on it was back down to 5.4, so no harm done,
and I fixed it for shot#2. I managed to tune the startup
to avoid runaways by tweaking Bz and increasing the RCUR 
offset to -2000.

On shot 5 Alex requested an additional 1 psi of neon in 
the bside lower plenum. We then experienced several disruptive
shots, earlier each time. On shot#8 I disabled the bside-lower
and the disruption went away. For subsequent shots, the
bside-lower mix was changed to 1psi Argon + 1psi neon, 
and the plasmas again ran into rampdown. This seems to 
provide circumstantial evidence that the neon is not a 
negligible perturbation. 

The upper null threshold was established by shot 10, and 
we changed to the lower null. It turned out to be necessary
to reduce the density ramp rate and seg2 PG3 program to
avoid a marfe in lower null reverse field. As the RF power was
increased to try to reach the L-H threshold it became 
apparent that the density was increasing with RF power in L-mode.
This could be an indication of outgassing from J-port, or
from somewhere other than the antennas as a result of heating.
It was necessary to reduce the ohmic target density in order
to match the density during RF with the value from the
upper null cases, 0.9 to 1.0e20. H-modes were obtained in 
LSN on shots 15 and 17. Shot 16 was the only fizzle of the 
first half of the run, and shot 18 disrupted early because
of a power supply fault (OH2L crowbarred). 

The Alfven damping run began on shot#20 (shot 19 was a no-power
shot because of two separate problems with camac Jorway setup
values, one on the critical TCI diagnostic.) This portion of
the run used limiter L-modes, as planned. The AMHD system had
also been piggybacking during the morning, and got some data
for both upper and lower null cases, but analysis is complicated
by the presence of the 500kHz beat between D&E. The second half
used RF from D alone or D+J. The density was reduced from 7e19
to 6e19 to get the best data from VTang's ion tail measurements.
These shots were plagued by runaways, and later by fizzles
which may have been exacerbated by my efforts to get rid of 
the runaways. There were 7 fizzles and one runaway-induced
short disruption over the span of shots#20-35, including one
string of four fizzles in a row. On the plus side, the RF 
worked flawlessly, so essentially all the shots that ran 
in this part of the run provided useful data. A scan of RF
power from 0.5MW to 2.5MW, plus an ohmic baseline shot, 
was completed. If we had had one more shot a higher power
3MW case would have been attempted. The between shot 
analysis seemed to indicate that the damping went through
a maximum in the power scan and was getting smaller at
2.5MW. Since the mode is expected to become unstable with
sufficient tail ions (more power), the far end of the 
scan would have been of interest, if the RF could get 
enough power in with only D+J.  

Most of the fizzles appeared to be cases of the plasma
running outside and bouncing once or twice, and the Bz 
evolution appeared to be too slow. However, the usual field 
tweaks, less co-current EF4 and more negative, i.e. outward,
Rcur offset, did not seem to help. In the end, the gas-head 
approach of increasing the pg4 puff seemed to work, though 
runaways persisted even with 29msec of puff and ratiomatic 
pressure above .06mTorr. The wall condition clearly was 
playing a role in this, since nothing close to that high 
a pressure was necessary during the diverted
shots earlier in the day. The starting Bz ended up much less
positive (by ~2mT) than ran nicely earlier in the day. It
may be that the "right" prescription would have been to 
try more positive EF4 and let the RCUR offset drive a faster
swing through zero to negative values. That's about the only
thing I didn't try during this sequence. 

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

   No Power         1
   Duds             0
   Fizzles          8
   Plasmas         26
   --------        ---
   Shots           35



Session Leader Comments
May 26 2006 09:12:14:057AM1060526001John RiceUSN, 1.0 MW, L-mode
May 26 2006 09:24:20:620AM1060526002John RiceUSN, 1.1 MW, L-mode
May 26 2006 09:49:51:023AM1060526003John RiceUSN, 1.2 MW, L-mode
May 26 2006 09:51:29:367AM1060526004John RiceUSN, 1.4 MW, L-mode
May 26 2006 10:08:52:570AM1060526005John RiceUSN, 1.5 MW, H-mode?
May 26 2006 10:23:44:807AM1060526006John Ricedisrupted
May 26 2006 10:38:10:947AM1060526007John Ricedisrupted
May 26 2006 10:54:57:947AM1060526008John RiceUSN, 1.6 MW ICRF, H-mode
May 26 2006 11:09:36:697AM1060526009John RiceUSN, 1.6 MW ICRF, H-mode
May 26 2006 11:30:37:430AM1060526010John RiceLSN, 3.0 MW ICRF, L-mode
May 26 2006 11:39:08:760AM1060526011John RiceLSN, 3.0 MW ICRF, L-mode
May 26 2006 11:55:20:663AM1060526012John RiceLSN, 3.0 MW ICRF, Super L-mode
May 26 2006 12:08:02:557PM1060526013John RiceLSN, 3.2 MW ICRF, Super L-mode
May 26 2006 12:20:12:120PM1060526014John RiceLSN, 3.4 MW ICRF, Super L-mode
May 26 2006 12:31:03:383PM1060526015John RiceLSN, 3.4 MW ICRF, lower density target, H-mode
May 26 2006 01:12:32:197PM1060526016John Ricefizzle
May 26 2006 01:00:02:180PM1060526017John RiceLSN, 3.2 MW ICRF, lower density target, H-mode
May 26 2006 01:12:46:213PM1060526018John Riceearly disruption
May 26 2006 01:41:02:807PM1060526019Joseph SnipesTurned over the run to MP404a Active AE Damping with ICRF. Start with inner wall limited plasmas like
1060309020 but with nl04 = 7 x 10^19 m^-2 to have more of a fast ion tail when we do add RF later. This shot
will be without RF as a baseline. Lower Hybrid tree error caused us to lose the shot.
May 26 2006 02:35:25:227PM1060526021Joseph SnipesShot 21: Repeat at nl04 = 6 x 10^19 m^-2 to improve fast ion tail and CNPA data.
q_AE set to 1.
May 26 2006 02:36:01:680PM1060526022Joseph SnipesShot 22: Set q_AE = 1.5. D-port ICRF only at 0.5 MW. Good shot.
May 26 2006 02:36:18:413PM1060526023Joseph SnipesShot 23: Fizzle!
May 26 2006 02:51:45:273PM1060526024Joseph SnipesShot 24: D port RF set to 1 MW. Good shot. q_AE = 1.5.
May 26 2006 03:37:40:960PM1060526025Joseph SnipesShot 25: Combining D and J to get 1.5 MW. Disrupted early.
May 26 2006 03:37:53:337PM1060526026Joseph SnipesShot 26: Fizzle.
May 26 2006 03:38:40:633PM1060526027Joseph SnipesShot 27: Good shot with 1.5 MW with D and J antennas.
May 26 2006 03:40:58:460PM1060526028Joseph SnipesShot 28: Fizzle.
May 26 2006 04:13:34:350PM1060526029Joseph SnipesShot 29: Fizzle!
May 26 2006 04:13:57:427PM1060526030Joseph SnipesShot 30: Fizzle!
May 26 2006 04:14:27:927PM1060526031Joseph SnipesShot 31: Fizzle!
May 26 2006 04:41:39:803PM1060526032Joseph SnipesShot 32; Good shot. Got 2 MW of RF. Looks like TAE damping is increasing with RF power!?
May 26 2006 04:41:57:757PM1060526033Joseph SnipesShot 33; Good shot. Got 2.5 MW of RF. Looks like TAE damping is still increasing with RF power!?
May 26 2006 05:01:14:100PM1060526034Joseph SnipesShot 34; Try no RF baseline to see if damping decreases again. Fizzle
May 26 2006 05:01:55:680PM1060526035Joseph SnipesShot 35; Try no RF baseline to see if damping decreases again. Got the baseline shot. Good shot.

Physics Operator Comments
May 26 2006 07:48:57:743AMSteve Wolfe
Setting up for 1060526 run.
I'll start off using the development edition of the new PCS GUI, 
since it has some features that almost do what I need to do. 

Import seg2 from 1060524012 (LSN) and turn off
Import seg3 from 1060523013 (USN) and turn on (I think 
  it's the same as what I've got, but do it anyway). 
  Turn on seg3.
Load/Clean, just so it's there in case I screw up the next part.
Load at 26-May-2006 07:33:14.00

Import seg4 from 1060309020,seg2. It says "0.8MA,5.4T, limited"
  All_P's: flip ef2byef4,ic_ef4u,ip
  v01-16: flip wires 1-9,11,12 (not Acoil or gas valves
  recalc preds:rcur,zcur2,zcur3,clearin,rxl,zxl,rxu,zxu
  Title to "+0.8MA ..."
Load/noclean (save it)
Build seg4; get one factor popup
Build seg2: no messages
Back to seg4:
  Load b21_proj to wire 9
  integrator C gate from 0.5 to 0.3sec
  V1-16: zero acoil_cur (from 2000A)
  Build. 
Load/Clean
 Load at 26-May-2006 07:48:36.00


May 26 2006 07:57:30:977AMSteve Wolfe
Continuing setup for 1060526. 
Bring up v17-32 screen for seg4.
There is a waveform in output_17 from the last AMHD run.
This gets loaded in INIT (and may be a design problem). 
It shouldn't hurt, but I'll zero it anyway.
   Note: I should add a zero option to the popup menu in edit_V2
While I'm at it, open the other v17 windows. Some haven't
been updated to recognize the gasjet trigger yet. Apply 
all of them.

Load/Clean
Load at 26-May-2006 07:57:16.00


May 26 2006 08:08:58:603AMSteve Wolfe
Continuing setup for 1060526. 
Now for the new stuff. I want to go ahead and
install the dpcs_ftae2 routine, and get rid of
the old dpcs_ftae routine. The pieces of code to
do this from PCS aren't ready for primetime, but
I'll use them anyway and see how badly they do.

Under TEST_PROS, choices are dpcs_ftae,dpcs_jet_trigger,new
  Select "NEW".
  In AddProcedure popup, 
    select dpcs_ftae and click "REMOVE"
    select dpcs_ftae2 and click "ADD"
    Dismiss.
Load/Clean
Load at 26-May-2006 08:03:43.00
 of course the TEST_PROS button won't have changed, since 
 I haven't written that code yet. I'll need to exit PCS and
 get back in to see it. 
First, bring up a traverser and check the model.
  \HYBRID::TOP.DPCS.LOADABLES.PROCEDURES:TEST_PROS:PROCEDURE_01
    is turned ON and contains "dpcs_ftae2" 
  PROCEDURE_2 still has dpcs_jet_trigger and is off
  PROCEDURE_3 is blank and is off
That worked, except that it should probably be OFF by 
   default after inserting? 

Quit PCS and reinvoke (without /nocopy)
Note that the TEST_PROS menu has changed properly.



May 26 2006 08:28:47:540AMSteve Wolfe
Now to test the dpcs_ftae2 routine in the live system

~$ cd /usr/local/cmod/codes/dpcs
Irby reports problem taking a test shot, but try anyway:
in IDL
IDL> test_init_ftae,1060526101
Seems to have run, I have output on amhd_freq and
amhd_freq_0 (outputs 17 and 18). 

There are some error messages in the logfile,
probably related to dpcs_fizzle since engineering pulse
file is not created by the test pro. 

Looks like dpcs_ftae2 ran ok. No missed samples. 
OK, program is probably working. 

Now use PCS to turn it back off. 
  TEST_PROS | dpcs_ftae2 | click Off then OK. 
Load/Clean 
Load at 26-May-2006 08:26:09.00
Check in the traverser. Node is now off. 
OK, aside from the fact that the TEST_PROS menu will still 
show dpcs_ftae2 in boldface, it's ready to go under
PCS control. 

May 26 2006 08:48:31:540AMSteve Wolfe
John's opening shot looks like it is programmed for
quite high density (1.05e20) and gets there too fast (.3sec)
The original shot seems to have made it without too bad
a marfe, but it's a concern. At least the current rise
for this case is programmed fast, which probably helps.
Argon/Neon puff is at 50msec. 

Br0 is at 0
PG4 is 20ms
EF4 is 1340
RCUR offset=-1200

No reason to change these yet. 

Ready to go, I think. 

May 26 2006 08:55:49:853AMSteve Wolfe
Turn dpcs_ftae2 on for first shot
Load/Clean
Load at 26-May-2006 08:55:16.00


May 26 2006 09:14:45:820AM1060526001Steve Wolfe
Shot#1: plasma to 1.74sec
No runaways, just a hint of a marfe around 0.3sec
D&E ok, 1MW total no J. No H-mode. 
NL04 just under 1.0 during RF. 
Bz looks too positive, some bounciness(?) in startup
Got outputs on AMHD output channels, center freq claims
to be ~700kHz.
I still had 165ka on the TF in seg1, leftover from 
yesterday. Fix that.
Next shot: repeat with more RF, keep an eye on Bz

May 26 2006 09:24:32:477AM1060526002Steve Wolfe
Shot#2: Drop seg1 tf back to 150kA (I'd left it from yesterday!)
 otherwise repeat with more RF, keep an eye on Bz
LH will try to fire at the end of RF pulse. 
Plasma to 1.7sec, marfe a little worse; still no H-mode at 1.1MW 
Bz still looks high, no runaways but long hesitation; 
 leave it for now. Pressure at t=0 is coming up, around .05
 this time. 
I'm getting the b22_jk not begin near zero error each shot.
This seems to be a digitizer problem; it's between 40 and 50mV. 

Next: repeat


May 26 2006 09:39:00:807AM1060526003Steve Wolfe
Shot#3:No PCS changes, rf will raise power 
plasma to 1.6sec only. Got some runaways early
this shot, bounces in startup. 
No H-mode, maybe just a hint of dithers.

Next: ef4 down 10A, tweak rampdown a little.

May 26 2006 09:51:56:087AM1060526004Steve Wolfe
Shot#4: ef4 from 1340 to 1330, 
tweak clearin rampdown a little slower.
plasma, lasted longer (1.8) but runaways worse.
Multiple bounces in startup; 
Density rise during rf doesn't look like an h-mode
but maybe in a dithery state (halpha fuzz).

Next: rcur offset from -1200 to -1600, more rampdown tweak 

May 26 2006 10:08:39:227AM1060526005Steve Wolfe
Shot#5: rcur offset from -1200 to -1600, 
reduce clearin rampdown more. 
Add 1psi Neon to bside-lower per aic request 
Load at 26-May-2006 09:54:32.00

plasma disrupted earlier, looks like an 
injection around .13sec took a small bite out of Ip.
Something coming in around 1.32sec too.
Possible very marginal dither-H transition at 0.807sec
trips rf briefly. 

next: rcur offset to -2000

May 26 2006 10:25:47:523AM1060526006Steve Wolfe
Shot#6: rcur offset from -1600 to -2000
early disruption, .71sec, injection or something 
starts at .66, before the RF. Gaps look ok. 
Startup looks good, no hesitation, although the
initial Bz still looks too positive. 

next: repeat. I'm suspicious of the extra neon in bside-lower
if we get another disruption I'm going to drop their puff.


May 26 2006 10:44:39:883AM1060526007Steve Wolfe
Shot#7: repeat. I'm suspicious of the extra neon in bside-lower
if we get another disruption I'm going to drop their puff.
Another disruption, around 0.45sec this time. The marfe is
worse. Prad starts taking off around .35 to .4sec
It looks like we're heating something up, or maybe
it's the neon. 

Next shot: Bside-lower off, fill NINJA per KMarr, but
don't fire it. 

May 26 2006 10:55:20:103AM1060526008Steve Wolfe
Shot#8: Bside-lower off, fill NINJA per KMarr, but
don't fire it. No PCS changes this time. See if turning
off argon/neon changes things. Else, we can try decreasing
the early pg3 puff in seg2

Plasma full length. H-modes at 1.6MW
 A one-data-point correlation. 
Next shot: B-side lower to 1psi Argon+1psi Neon
and enable. Also NINJA will fire. 



May 26 2006 11:09:39:820AM1060526009Steve Wolfe
Shot#9: B-side lower to 1psi Argon+1psi Neon and enable.
 Also NINJA will fire. 
Plasma full length, h-modes, marfe or injection before rf
one at .13sec, one at .52sec, survived both
Data system is hanging. 

Next: on to LSN case (seg2)



May 26 2006 11:28:25:867AM1060526010Steve Wolfe
Shot#10:  on to LSN case (seg2), 
copy nl04 and ip traces from seg3 to seg2
copy pg3 and pg2 traces from seg3 to seg2
hand tweak the clearin rampdown. 
Turn off seg3 turn on seg2

plasma full length, marfe from .4 to .77sec
3MW (on and off), no Hmode, density is up during rf,
probably from marfe plus antenna fueling. 

Next: try dropping pg3 in seg2 between .25 and .4sec


May 26 2006 11:40:01:947AM1060526011Steve Wolfe
Shot#11:try dropping pg3 in seg2 between .25 and .4sec
NINJA had not been enabled previously, will fire this time

plasma full length, injections better but not gone, Marfe
no different, density still too high. 

next: turn off pg3 in seg2 entirely, slow down nl04
program. 

May 26 2006 11:56:40:710AM1060526012Steve Wolfe
Shot#12: turn off pg3 in seg2 entirely, slow down nl04
program, reduce from 1.05 to 1.0e20
plasma full length, marfe is gone, still no Hmode
density rising during RF due to antenna outgassing? 
Before rf, nl04 is only .9e20

next: put nl04 program back to 1.05e20

May 26 2006 12:08:17:930PM1060526013Steve Wolfe
Shot#13: put nl04 program back to 1.05e20
plasma full length, still L-mode, 3.2MW
still no marfe, density a little low before rf
but still rising during rf

next: repeat with more power

May 26 2006 12:21:30:213PM1060526014Steve Wolfe
Shot#14: repeat with more power
plasma to 1.87sec, still L-mode, 3.5MW
nl04 still increasing to 1.3e20 during RF. 
We seem to have a lot of gas coming off the antenna.

next: reduce nl04 program by 15%

May 26 2006 12:33:18:087PM1060526015Steve Wolfe
Shot#15: reduce nl04 program from 1.05 to .90e20
Load at 26-May-2006 12:22:58.00
plasma, h-modes. 

next: reduce rf power to bracket the threshold. 

May 26 2006 12:50:26:337PM1060526016Steve Wolfe
Shot#16: reduce rf power to bracket the threshold. 
fizzle. Big lumps on the Halpha, starting around
9msec, strong current rise, then dies. 
pressure and fields look the same, bz a little less 
positive early

next: ef4 back to 1340

May 26 2006 01:00:22:290PM1060526017Steve Wolfe
Shot#17:  ef4 back to 1340 from 1330
plasma full length, h-modes

next: one more on MP#415, lower rf to bracket threshold

May 26 2006 01:16:07:820PM1060526018Steve Wolfe
Shot#18: one more on MP#415, lower rf to bracket threshold
Early disruption, PF crowbar. 
Disrupts at .545sec, caused by oh2L crowbar at .469sec

Next: Move on to the Alfven run, start with 
limiter discharge in seg4. 

May 26 2006 01:37:09:307PM1060526019Steve Wolfe
Shot#19:  Move on to the Alfven run, start with 
limiter discharge in seg4. 
Turn off seg2 on seg4, drop density to 7e19

CAMAC arming error on TCI need to abort

May 26 2006 01:56:08:477PM1060526020Steve Wolfe
Shot#20: Move on to the Alfven run, start with 
limiter discharge in seg4. 
Try again. TCI reset JORWAY setting, LH tree set noinclude

plasma full length, looked limited
lots of little injections, rf firing late for tuning,
just under 1MW from D&J, clean pulses.

Got an oh coax resistance warning; dpcs_fizzle can't
help on a crowbar!

next: reduce nl04 to 6e19

May 26 2006 02:05:24:870PM1060526021Steve Wolfe
Shot#21: reduce nl04 from 7e19 to 6e19
Early runaways, one bounce in startup. 
Disrupted at 1.63sc, possible locked mode in rampdown. 

Next: raise pg4

May 26 2006 02:17:24:353PM1060526022Steve Wolfe
Shot#22: raise pg4 from 20 to 23ms 
plasma, still some early runaways
Didn't load the gas change!
J didn't fire, only got 0.5MW

Next time: pg4 from 20 to 23ms

May 26 2006 02:28:52:383PM1060526023Steve Wolfe
Shot#23: raise pg4 from 20 to 23ms
Load at 26-May-2006 14:17:13.00
fizzle. Maybe I shouldn't have added gas.
Looks like an injection at .011sec on halpha; no bounce.
I think it was a random flake. 

next: ef4 to 1335, pg4 to 22msec


May 26 2006 02:41:30:227PM1060526024Steve Wolfe
Shot#24:ef4 from 1340 to 1335, pg4 from 23 to 22msec
plasma, but lots of runaways. No obvious bounces though. 
1MW of RF this time. 

next: pg4 back up to 23ms

May 26 2006 02:56:53:273PM1060526025Steve Wolfe
Shot#25:pg4 from 22 to 23ms
runaway shot. big injection at .345 kills the
current. 

next: increase pg4 to 26msec, pg3 in seg2

May 26 2006 03:07:50:960PM1060526026Steve Wolfe
Shot#26:pg4 from 23 to 26ms, pg3 increase in seg1 and 
before .25sec in seg4
fizzle. This one looks like too much pg4

next: pg4 back to 24msec 

May 26 2006 03:21:20:010PM1060526027Steve Wolfe
Shot#27:pg4 from 26 to 24, still increased pg3 before .25sec
plasma no runaways
one small injection .83sec
RF from D+J 1.5MW

next: repeat


May 26 2006 03:31:27:523PM1060526028Steve Wolfe
Shot#28: repeat
fizzle. need to drop the gas and hope
the runaways stay away. 

May 26 2006 03:44:26:820PM1060526029Steve Wolfe
Shot#29: pg4 from 24 to 22ms,
rcur offset from -2000 to -1800
Br0 from 0 to .0002
Fizzle again. This time it bounced!



May 26 2006 03:58:52:903PM1060526030Steve Wolfe
Shot#30: rcur offsetfrom -1800 to -2200
pg4 from 22 to 23ms
fizzle, bounced again. Looks a lot like 29

Raise pg4 again



May 26 2006 04:10:37:457PM1060526031Steve Wolfe
Shot#31: pg4 from 23 to 25msec. If this doesn't work
put br0 back to 0, more negative on ef4
Another fizzle. still seems to be bouncing outside.
Bz is not rising fast enough. 
Br0 back to 0, EF4 to 1325


May 26 2006 04:29:42:427PM1060526032Steve Wolfe
Shot#32: Br0 back to 0, EF4 to 1325
raise pg4 to 27msec
plasma, some runaways but at least it ran!
slight bump on the halpha, no bounce but swings outside
Bz still not ramping very fast compared to Ip
Got 2MW clean from D+J





May 26 2006 04:39:19:333PM1060526033Steve Wolfe
Shot#33: No pcs changes, raise power
plasma, runaways worse, saturated before the RF 
bounced once and survived. 
2.5MW clean until 1.35sec
Bz is not ramping fast enough. Do I have the
right direction on the rcur offset? 

next: No pcs change, rf off for baseline case





May 26 2006 04:47:48:863PM1060526034Steve Wolfe
Shot#34:  No pcs change, rf off for baseline case
fizzle bounced twice. 

raise pg4?




May 26 2006 05:00:18:757PM1060526035Steve Wolfe
Shot#35: pg4 from 27 to 29ms; I can't believe the
gas needs to be this high, but I don't understand 
why the Bz is not ramping up faster

plasma with runaways, disrupted at 1.65sec
At least it ran and Joe and Jason
got there no RF case to complete the scan. 

End of Run



May 26 2006 06:11:58:803PM1060526035Steve Wolfe
After the last shot #35, turn off dpcs_ftae2
using the PCS screen interface. 

Engineering Operator Comments
ShotTimeTypeStatusComment
109:02:04:023AMPlasmaOk
209:16:43:010AMPlasmaOk
309:32:22:807AMPlasmaOk
409:47:03:913AMPlasmaOk
510:00:51:370AMPlasmaOk
610:15:35:227AMPlasmaOk
710:35:15:413AMPlasmaBadDisruption PF breaker open OH1 self powered
810:49:47:883AMPlasmaOk
911:02:14:337AMPlasmaOk
1011:22:51:447AMPlasmaOk
1111:35:46:773AMPlasmaOk
1211:51:28:663AMPlasmaOk
1312:04:01:040PMPlasmaOk
1412:16:32:633PMPlasmaOk
1512:28:56:663PMPlasmaOk
1612:43:34:477PMPlasmaOk
1712:55:59:430PMPlasmaOk
1801:08:29:900PMPlasmaOk
1901:33:57:100PMPlasmaBadNo Power TCI
2001:46:23:850PMPlasmaOk
2101:59:39:087PMPlasmaOk
2202:12:03:743PMPlasmaOk
2302:24:30:273PMPlasmaOk
2402:36:57:743PMPlasmaOk
2502:51:22:993PMPlasmaOk
2603:03:51:557PMPlasmaOk
2703:16:20:320PMPlasmaOk
2803:28:49:180PMPlasmaOk
2903:41:21:273PMPlasmaOk
3003:53:47:190PMPlasmaOk
3104:06:11:190PMPlasmaOk
3204:18:35:210PMPlasmaOk
3304:31:03:990PMPlasmaOk
3404:44:39:130PMPlasmaOk
3504:57:02:570PMPlasmaOk