Alcator C-Mod Run 1070531 Information

Back to runs

Miniproposals
Miniproposal:483
Date Filed: 4/27/2007
Title:Initial Experiments Measuring Pedestal Characteristics USING CXRS
First Author:Kenneth Marr
Session Leader:Jerry Hughes (shots 1-27)
Session Leader:Kenneth Marr (shots 1-27)

Operators
Session leader(s):Jerry Hughes,Kenneth Marr
Physics operator(s):Steve Wolfe
Engineering operator(s):Bill Cochran,Andy Pfeiffer,Gary Dekow

Engineering Operator Run Comment
SL Plan for MP 483: "Initial Experiments Measuring Pedestal Characterist

Session Leader Plans
Entered: May 30 2007 04:59:43:160PM
Author: Jerry Hughes
SL Plan for MP 483: "Initial Experiments Measuring Pedestal
Characteristics using CXRS"

Goals for this experiment include the measurement of ion temperature
pedestal and its response to changes in collisionality, and the
examination of boron velocity changes to stored energy and magnetic
topology. Data are to be acquire at distinct values of plasma current,
while attempting to achieve low collisionality and high stored energy.

Ip will range from 0.6 to 1.2MA.
B=5.4T for all shots.
DNB timing 25ms on 15ms off.

***NINJA enabled with 8psi D2***

RF in steps:
1MW starting at 0.6s
2MW starting at 0.9s
max. available starting at 1.2s


Begin with LSN geometry, switch to USN later in the day. Outer and
inner gap (mostly the outer gap) should be maintained as steady as
possible. LSN: Load shot 1070516005 and adjust Ip, target nl04 as
called out below. USN: Load shot 1070525013 and adjust Ip, target
nl04.

At least 2 shots at each of the following conditions:

1)LSN, I=0.6MA, nl_04 = 0.4*10^20 m^-2
2)LSN, I=0.6MA, nl_04 = 0.6*10^20 m^-2
(consider going to I=0.8MA, nl_04=0.6-0.8*10^20 m^-2 if trouble
getting H-modes)
3)LSN, I=1.2MA, nl_04 = 0.6*10^20 m^-2
4)LSN, I=1.2MA, nl_04 = 0.8*10^20 m^-2
5)LSN, I=1.2MA, nl_04 = 1.0*10^20 m^-2
(Consider going to I=1MA, if trouble getting H-modes)
6)USN, I=0.6MA, nl_04 = 0.8*10^20 m^-2
7)USN, I=1.2MA, nl_04 = 0.8*10^20 m^-2

If there is extra time at the end of the run go to LSN, I=1.0MA,
nl_04=0.8*10^20 m^-2, constant RF power at 1MW above threshold starting
at T=0.7s. Run several shots stepping up DNB current from 5.5 to
6.5A.

Physics Operators Plans
Entered: May 30 2007 04:54:35:050PM
Author: Steve Wolfe
Physop Plan and Engineering setup for Thursday, May 31, 2007

MP#483 "Initial Experiments measuring pedestal characteristics using CXRS" 
SL: Marr, McDermott, Hughes
PO: Wolfe

Overnight boronization should be carried out on Wednesday, May 30, followed 
by two hours of ECDC in Helium.

Boronization prescription: 
  Use EF4 vertical field, 200 Amps as on 1070514
  Sweep = 44/85/70 (min/max/dwell)
  Dwell/period=30/60
  Pressure setting: tc6=35mTorr (tc3<1mTorr)
  Run boronization until 05:30AM on Thursday

Following boronization, run ECDC two hours, finishing by 08:00
  ECDC in helium, 5e-5 Torr
  sweep 44/103/45 (min/max/dwell)

******************************************************************
Engineering setup:
 
 Power Systems as on 1070516005
 Acoil: +Dtop -Dbot -Jtop +Jbot (standard) hybrid enabled
 
Gas setup: 
 Fill B-Top with 6 psi D2 Hybrid enabled (PG4)
 fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
 leave B-side upper as is Hybrid DISABLED (PG2)
 fill B-main with 40 psi D2 Hybrid enabled (PG3)
pump out NINJA and backfill with 8 PSI of D2, then disable.

Enable the following gate valves and shutters: 
  ECE, DNB, VUV, Z-bolo shutters
Torvac setup: Pumpstack gatevalves open
  Leave RGA's closed and off. 

ICRF setup: FMIT#1 and 2 in RUN-On by 8:30
            FMIT#3 and 4 don't bother (unless Wukie changes his mind)
LH: None 

*****************************************************
Physop plan:
  Import segment 2 from 1070516005 
  Change Ip from 0.8 MA to 0.6MA
  Decrease Nl_04 to 0.4e20 (from 0.8e20)
  
  Follow shot sequence per SL_PLAN:
  At least 2 shots each with
    1) LSN 0.6MA 0.4e20
    2) LSN 0.6MA 0.6e20 
       Possibly change to 0.8MA, 0.6/0.8 e20
    3) LSN 1.2MA 0.6e20
    4) LSN 1.2MA 0.8e20
    5) LSN 1.2MA 1.0e20
       Possibly change to 1.0MA

  Since J-port not available, it seems unlikely we would go to
  the upper null part of this experiment, but if we do use 1070525013 and 
  change current, density to 
    6) USN 0.6MA, 0.8e20
    7) USN 1.2MA  0.8e20

  All the above use stepped RF per SL_PLAN. DNB timing 25ms on/15ms off.

  If there is time, go to LSN 1.0MA 0.8e20, constant RF, stepped DNB current.
  (See SL_PLAN).

Session Leader Summaries
Entered: May 31 2007 05:52:18:210PM
Author: Jerry Hughes
The run was reasonably successful in terms of obtaining the plasma conditions
called out for in the run plan. LSN H-modes were obtained in 0.6MA, 1.0MA and
1.2MA with target density scans at each current. The steadiest H-modes obtained
were at 1.0MA and below, where EDA operation is predominant, and good spectra
were obtained using CXRS diagnostics. A significant span in H-mode stored energy
was also obtained through the variation in Ip, Prf (40kJ provide a range of points for the correlation of rotation with energy/pedestal
pressure. Confinement was observed to be quite good early in the day, with
substantial temperature pedestals, and H-factors occassionally approaching 1.7.
This tended to settle around a more pedestrian 1.4 as the day wore on. Overall,
though, impurities and injections were not a big concern, and it looks like the
overnight boronization had its usual good effects without significant recovery
cost.

Maximum available RF power turned out to be approximately 2MW out of D+E
antennas. Because this was not very far above the threshold power anyway, we
quickly abandoned the three-tier power steps and moved on to a flat RF pulse.
The best RF results were obtained with total power below 2MW. An optimistic
attempt to achieve USN H-mode at 1.2MA resulted in two USN L-modes. We were
simply too power-starved to get an L-H transition.

The last two plasmas (25,27) were attempts at steady EDA H-modes, first with the
DNB operating, and the 2nd without, so that McDermott could evaluate non-beam
background in the CXRS diagnostic.

See McDermott's and Marr's summaries for further details.


Entered: May 31 2007 10:12:21:140PM
Author: Kenneth Marr
Today's run covered a good portion of the goals as stated in the mini-proposal for the innerwall GPI system. Specifically we were interested in covering a range of stored energy and taking data in both L-mode and H-mode.

We began at low puff pressures and puff lengths in order to keep from perturbing the low density shots. These appeared to give sufficient signal increase and the data showed a visible movement in wavelength from L to H-mode. As we moved to higher currents and densities, I increased the puff lengths and added a third puff. The density continued to be unchanged by the amount of gas we were puffing. At one point we decreased the puff length but increased the puff pressure to 12psi so as to provide a stronger 2nd and 3rd puff. For the two USN shots late in the day, that did not achieve H-mode, the density remained constant under 'heavy' puffing.

Around shot 7, the signal from a few inner wall views was found to be saturating and the gain on the spectrometer was reduced.

The shots showed strong Zeeman splitting at the inner wall views and a measurable increase in signal during the puffs. The H-mode also affected the signal levels, but the background views should give simultaneous measurement of the background plasma. Unexpected lines near the lines of interest may complicate analysis, however.

Overall, the data should be able to be analysed for velocity and temperature profiles and these profiles can be compared with Thomson Scattering and Hirex measurements. Shots that were not achieved include USN shots in H-modes, higher power LSN shots utilizing all ICRF antennae, and a possible scan of the left gap.
Entered: Jun 1 2007 12:23:53:630PM
Author: Rachael Mcdermott
The goals for the experiment were:
1) To measure the response of the ion temperature pedestal width to changes in collisionality via edge CX measurements, and to determuine whether the ion temperature pedesal differs from the electron pedestal in low collisionality regimes.

2) To measure the changes in the edge velocity profiles to changes in stored energy and magnetic topology.

To do this the MP called for a range of plasma currents from I=600KA to 1.2MA, with plasma density ln_04 from 0.4-1.2*10^20m^2. In each of these conditions RF power was to be stepped up in three tiers throughout the shot. In each of these conditions a constant EDA H-mode was required to make reliable CX pedestal measurements.

The run was reasonably successful. At Ip=600KA we obtained steady EDA H-modes at two different densities ln_04=0.5, and 0.8*10^20. At 1.2MA we had trouble getting the EDAs and instead ended up with ELM-free, which unfortunately, were not steady enough for reliable CX pedestal measurements. We dropped the current to 1MA, where we obtained EDA's at 3 different densities, nl_04=.6,.8, and 1.0*10^20m^2.

The DNB was operating very well at 6Amps. Unfortunately, we discovered that the current rise time to 6amps, was not the anticipated 13ms but closer to 24ms, which limited the CX timing. We ran most of the day with 34ms on period and a 13ms off period. This was still sufficient to make pedestal measurements during the flat top of the EDA H-modes. The active CX signal was very good, the best we've seen so far varying between 20 and 60% depending on plasma conditions.

Two USN shots were attempted, but ended up with beautiful USN L-mode plasmas, and a couple of fizzles/disruptions.

At the end of the day we went back to a background subtraction piece of MP 482, and obtained two shots at Ip=1MA, and nl_04=1.0 with very similar L-H transitions, one with DNB and one. The CX signal increase during the beam shot was very clear.


Physics Operator Summaries
Entered: May 31 2007 05:58:10:570PM
Author: Steve Wolfe
Physop summary for Thursday, May 31, 2007

SL: Hughes, Marr, McDermott
PO: wolfe
EO: Cochran, Pfeiffer, Dekow
MP#483 Pedestal characteristics

This was a reasonably successful run. We got most
of the cases from the run plan covered, although 
some points were abandoned after one shot because the 
H-mode conditions were not steady enough.

We ended up with useful data at 600kA, 1.0MA and 1.2MA in
lower null. Only the high current (1.2MA) Upper null condition
was tried, and there was not enough power from the RF to get H-mode
at either 1.2 or 1.0e20. We also ended up with a 1.2MA disruption
in upper null, which led to a fizzle. Good EDA H-modes were obtained
at 1.0e20 and 1.0MA; lower densities were marginal for EDA, and
gave typically 3 H-modes, of which the last was the most EDA-like.

The run got off to a late start because of power system problems,
first a breaker/OH1 fault that wouldn't reset and then a problem
with the PLC program monitoring the EF1U comm bank charge. There were
also some data system problems before we got going. The first plasma
shot was #4, at about 10:30. 

Later in the day we lost another hour to a problem with HEAT system. The
heater alley breaker tripped on over-temperature, and further investigation
revealed a group of TC's near C-port that were reading very high, due to
their cable being encased in ice. 

Some small changes in the gap program were required to put the 
pedestal where the different diagnostics wanted it. I tried modifications
to the RCUR gain to try to steady the outer gap during L-H-L transitions
and RF trips, but this was not very successful. Increasing the P gain
seemed to drive rcur a bit unstable. I set up to try integral gain
(putting wire 1 on Integrator A in the \\hybrid::top.config.wires),
but then the SL requested we move on to 1.2 MA, so I never implemented
it. Wire 1 remains on Integrator A, since it can't hurt. It may be useful
to try this approach in the future. 

The machine ran well after last night's boronization, with few injections
and reasonable density control. We had no difficulty going from 0.6 to 1.2MA, etc. I adjusted the IC_EF4 current on each change of Ip program, but it's not
obvious this was needed. The higher density 1.2MA cases tended to disrupt in 
rampdown with EF2's going to zero; this was remedied by slowing down the
negative ramp on CLEARIN after 1.5sec.  Some changes to segment 1 pre-puff
(PG4) were made to compensate as we went up and down in current and density. 
Gas puff adjustments after disruptions were not as successful, and we had 
a few fizzles. The last two shots were supposed to be a matched pair 
to test background subtraction, and I had to beg for an extra shot
after 17:00 when #26 fizzled. 

Before the run I made a change to the pre-charge OH2 program to try to avoid
the demand increasing above 100V, especially on OH2U, during the time before
the switch closes at -0.7sec. This was partially successful, but the demand
still goes above what the supply can do between -.56 and -.36sec. A decrease 
in the Pgain or another delay in the IC_OH2 program could help avoid this. 
The problem seems to arise because the OH2 current is held back by induced
voltage from OH1 and EF2's during this interval. The OH2's do eventually 
get up to their programmed current, but it might be better to avoid the 
excess demand because of wind-up issues with the internal integral gain 
in the voltage feedback in the supplies. 

Scorecard:
           Tests/No power    3
           Duds              0
           Fizzles           3
           Plasmas          21 (20 into rampdown)
           ============     ==
           Shots            27

Session Leader Comments
May 31 2007 09:00:48:997AMJerry HughesI'm driving today, on behalf of Ken and Rachael.
RF will probably take a finite number of shots to tune up.
Ken is enabling the NINJA puff for shot 1.
May 31 2007 09:06:24:080AM1070531001Kenneth MarrNINJA enabled. .4s for 100ms and 1.0s for 200ms. 8psi D2. CXRS 494.4nm B V emission.
May 31 2007 09:50:39:603AM1070531001Jerry HughesNo power shot. Power supply charging error.
May 31 2007 10:12:19:610AM1070531002Jerry HughesNo power test.
May 31 2007 10:16:03:473AM1070531003Jerry HughesNo power test.
May 31 2007 11:01:09:910AM1070531004Jerry HughesShot went off well. RF ran clean as programmed, but outgassed a bit, overfueling
the plasma. EDA H-mode, with RF tripping out. Repeat. Steve will try to improve
steadiness of the right and left gap.

Fairly substaintial Te pedestal in that first H-mode. A solid 500eV.
May 31 2007 10:58:01:050AM1070531005Kenneth Marr1st ninja puff lengthened to 120ms.
May 31 2007 11:10:39:260AM1070531005Jerry HughesBetter RF on the third tier. Got a steady H-mode at the end. Repeat,
and see if the density comes down.
May 31 2007 11:11:21:573AM1070531006Kenneth Marr2nd ninja puff moved earlier to .95s, 200ms. 3rd NINJA puff added at 1.2s for 250ms.
May 31 2007 11:33:53:957AM1070531006Jerry HughesDensity still a little higher than called for in the flattop, presumably
due to RF outgassing. H-modes don't look as great. Looks like we have sufficient
data on all the diagnostics. Time to move on to the higher current.
Next shot: Ip=1.2, slightly higher nl04.
May 31 2007 11:26:31:390AM1070531007Kenneth Marr2nd ninja puff moved to 0.93 s.
May 31 2007 11:47:48:150AM1070531007Jerry HughesIp=1.2MA, nl04 program is 6e19. RF raises nl04 to 8e19 at the time of transition.
Several H-modes, starting very ELM-free and becoming more EDA as pedestal ne
increases.
Next shot: Steve will make the flattop earlier, and we will delay the first RF
pulse, so we can get a steady L-mode portion at full current.
May 31 2007 12:13:37:470PM1070531007Kenneth MarrNINJA increased to 12psi. 0.5s for 100ms. 0.93s for 150ms. 1.2s for 200ms.
May 31 2007 11:43:35:397AM1070531008Kenneth Marr1st NINJA puff at .5s and 150ms.
May 31 2007 12:24:19:383PM1070531008Jerry HughesIp=1.2MA, nl04=6e19
H-modes, ELM-free
May 31 2007 11:58:35:420AM1070531009Kenneth MarrAB-LIM added for 3rd puff at 1.2s.
May 31 2007 12:27:18:400PM1070531009Jerry HughesIp=1.2MA, nl04=8e19
H-modes, ELM-free, but longer. Radiated power rise is liesurely, and reasonably
high Te pedestal and confinement in the first H-mode.
May 31 2007 12:33:33:230PM1070531010Jerry HughesIp=1.2MA, nl04=8e19
More H-modes, ELM-free. Decent confinement. No Thomson.
Next shot: raise density
May 31 2007 12:28:45:853PM1070531011Kenneth MarrNINJA Changed to 12psi. 0.5s for 95ms. 0.8s for 150ms. 1.2s for 200ms.
May 31 2007 12:44:55:860PM1070531011Jerry HughesThis is probably all we're going to get at this current.
Next shot: Drop to 1.0MA;
keep density the same. Try to get a steady EDA.
May 31 2007 12:44:22:407PM1070531012Kenneth Marr2nd Ninja puff reduced to 125ms.
May 31 2007 12:56:56:503PM1070531012Jerry HughesOnly ~1MW of RF throughout pulse. A few short H-modes. Try again.
May 31 2007 01:43:34:130PM1070531013Jerry HughesRF didn't do so well. Edge TS HV was off, and the warnings I tried to institute
earlier didn't get sent to me.
May 31 2007 01:54:26:557PM1070531015Jerry HughesGreat EDA H-mode. Decent data all around. Drop to 8e19 for next shot.
May 31 2007 01:55:28:277PM1070531016Kenneth MarrNinja set to 0.5s for 110ms; 0.8s for 180ms; 1.2 for 200ms
May 31 2007 02:21:15:473PM1070531016Jerry Hughes3 H-modes. The last is reasonably steady. R & K are happy. Thomson looks OK.
Drop to 6e19 for next shot.
May 31 2007 02:24:49:583PM1070531017Jerry HughesAgain, the third H-mode isn't bad. Its colder and more EDA-like.
Next shot: Moving back to low current. Ip=600kA. nl04=8e19.
May 31 2007 02:37:27:277PM1070531018Jerry HughesShot runs as called for, except for RF tripping out starting around 1s.
Ip=600kA. nl04=8e19. Pretty typical low current EDA.
Next shot: Try to get a steadier high current point. Call up shot 11, increase
target nl04 to 1.2e20.
May 31 2007 02:30:54:710PM1070531019Kenneth Marr3rd ninja puff extended to 250ms
May 31 2007 02:37:58:027PM1070531019Kenneth Marr1st Ninja puff moved to 0.5s. RF also delayed 100ms to allow flattop to develop.
May 31 2007 03:37:43:533PM1070531019Jerry HughesLong delay to address runaway heater problem.
Shot went off: 1.2MA, nl04=1.2e20
RF kind of fizzles out, leaving us with what looks like dithering Ohmic H-modes.
Next shot: Repeat, try to improve RF.
May 31 2007 03:46:41:740PM1070531020Jerry HughesFizzle.
May 31 2007 04:09:51:500PM1070531021Jerry HughesMany radiative H-modes. Raising density did not help us, relative to shot 11.
Are we wearing off the boronization?
Next shot: Same parameters, switch to USN. No guts, no glory.
May 31 2007 04:18:32:347PM1070531022Jerry HughesA beautiful USN L-mode, with a bonus sharkfin at the end.
Only got 700kW from E, 0 from D. Yijun says lower the density. Yes, master.
Next shot: USN, 1.2MA, nl04=1e20
May 31 2007 04:37:25:947PM1070531023Jerry HughesA beautiful USN L-mode, up to 1.13s, and beyond that we will say no more.
Only 1.6MW of ICRF power is just not enough to get into H-mode in this
unfavorable geometry. So, give up, and try to get Rachael some steady
H-modes a la shot 15.
Next shot: LSN 1MA, nl04=1e20
May 31 2007 04:53:37:563PM1070531024Jerry HughesFizzle.
May 31 2007 05:19:19:540PM1070531026Jerry HughesFizzle.
May 31 2007 05:19:55:620PM1070531027Jerry HughesAlmost identical to Shot 25. Exactly what was needed.

Physics Operator Comments
May 30 2007 05:51:04:917PMSteve Wolfe
Setting up for tomorrow's run. 
Bring up PCS as from Bill's last shot today. 
Notice that the dpcs_ftae2 routine that Jason asked to have turned on
 had disappeared, apparently when they went to upper null. This shot
 has only the obsolete routine dpcs_ftae in the menu. Remove this, and
 load up the dpcs_ftae2 procedure and turn it off. May as well keep this
 one around in case Jason or Joe wants it. 

I think that the segment 3 setup is from the same shot I want to load,
but may as well do everything from scratch. 

Turn off seg3, turn on seg2
Import seg2 from 1070516005
  Change Ip from 0.8 to 0.6MA
  Change nl04 from 8e19 to 4e19
  Change Integ C gate from 0.3 sec to 0.2sec
  Change seg2 title. 
  Build seg
Import seg3 from 1070525013
  Change Ip from 0.8MA to 0.6MA
  Zero Acoil_cur feedforward
  INteg gate C to 0.2sec
  Change seg3 title
  Build seg 3
Save as /home/wolfe/pcs_scratch/*_1070531000 (just for backup)
Load into Model
Load at 30-May-2007 17:50:29.00
Open tree /home/wolfe/pcs_scratch      -1
Open tree done

Check 

  

May 31 2007 08:18:58:560AMSteve Wolfe
Continuing setup for MP#483 on 1070531
Bring up PCS and confirm the model still contains 
the segments I set up yesterday. 

In segment 1, change waveform on IC_OH2 (wire10) to
avoid overvoltage before switch close at -0.7sec: 
add a point at -0.7,10000; 
also change initial point to 0.0A from +318A
Note PG4=18ms, IC_EF4U=-1315, BR_0=-.0030, RCUR=1000.
Change IC_EF4U from -1315 to -1330

Segment#2:  Note TF is set at -145kA; SL_PLAN says 5.4T, 
so change it to -150kA. Segment 3 is already at -150kA.

Change Chopper voltage from +100 to 0. (Where does this 
ancient hack keep coming from?)

ZCUR still has funny drop from -.009 to -.015 between
1.2 and 1.5sec. Leave it for now. Also, CLEARIN seems 
to go from (.003,1.0) to (.005,1.5) for no obvious reason.
I suspect they will want this more constant, but leave it 
for how. 

Enough for now. Load it.
Load at 31-May-2007 08:18:23.00
Open tree /home/wolfe/pcs_scratch      -1
Open tree done



May 31 2007 09:01:52:483AMSteve Wolfe
There will be a (hopefully) brief delay while the engineers
investigate a fault indication on the OH1 supply.

May 31 2007 09:52:41:450AM1070531001Steve Wolfe
Shot#1: program says 600kA, 4e19, 5.4T
tokamak says ...
No power shot. EF1 comm bank not charging. 
Over 2 minutes in check, so DPCS will time out. 



May 31 2007 10:08:07:220AM1070531001Steve Wolfe
Shot#2: No power cycle for test of EF1 comm bank charging 



May 31 2007 10:14:59:707AM1070531003Steve Wolfe
Shot#3: Will be another no power cycle for test of EF1 comm bank charging 
and associated PLC logic. 


May 31 2007 10:50:30:080AM1070531004Steve Wolfe
Shot#4: good plasma, cmodws30 froze and I had to reboot. 


May 31 2007 11:06:06:993AM1070531005Steve Wolfe
Shot#5: Adjust CLEARIN flat at .003, to try to steady both gaps.
Get rid of ZCUR ramp after 1.2sec
Leave startup alone, although could use a little more gas. 

plasma, hmode at 1.24sec. Outer gap still moving out at the end
Next: Increase gain on RCUR to try to improve outer gap




May 31 2007 11:24:06:530AM1070531006Steve Wolfe
Shot#6:  Increase P gain on RCUR from 6 to 9 at 1.0sec 
to try to improve outer gap
Lower nl04 program from 4 to 3e19. 
plasma. Rcur is less steady, maybe a little too much gain!

Next: back off on RCur gain from 9 to 6.15 again
Try putting Integrator A on wire 1 and turning on Integral gain

May 31 2007 11:41:20:427AM1070531007Steve Wolfe
Shot#7: back off on RCur gain from 9 to 6.15 again
Try putting Integrator A on wire 1 and turning on Integral gain at 4 from 
1.0 to 1.5sec

Change of plan- Next go 1.2MA, 0.6e20; IC_EF4U=3000 (from 2000)
Turn the Integral gain on RCUR back off, leave RCUR P=6.15
Plasma full length. Three H-modes, all look ELM-free
q95~3.4

Want left gap 3mm smaller, maybe bring current up faster



May 31 2007 11:53:45:917AM1070531008Steve Wolfe
Shot#8: left gap 3mm smaller, maybe bring current up faster
CLEARIN from .003 to 0.000, RCUR from .6605 to .6590
program IP to 1.2sec at .55s, try to get it there by 0.6; will
delay RF and/or NINJA accordingly.

Plasma. Ip is up a little sooner. Inner Gap is at 1cm, somewhat
less early, may need to readjust before 0.7sec?


May 31 2007 12:10:41:440PM1070531009Steve Wolfe
Shot#9: NL04 from 0.6 to 0.8e20
plasma full length, higher density, still 3 hmodes.
stored energy down a little, to 159kJ, RF still ratty.

Next: NINJA puff changes, otherwise repeat?



May 31 2007 12:23:43:070PM1070531010Steve Wolfe
shot#10: NINJA puff changes, otherwise repeat?
plasma, still 3 h-modes, first maybe a bit longer 

Next: raise nl04 to 1.0e20


May 31 2007 12:36:08:040PM1070531011Steve Wolfe
shot#11: raise nl04 to 1.0e20. Drop pg4 from 18 to 17ms
Disrupts in rampdown, 1.74sec, 600kA
Only two hmodes, slower density rise. 

Next: Drop current to 1MA, leave nl04 at 1.0e20 
(skip USN for now)


May 31 2007 12:49:36:970PM1070531012Steve Wolfe
shot#12:  Drop current to 1MA, IC_EF4U from 3000 to 2500A
 leave nl04 at 1.0e20
Drop pg4 from 17 to 16msec (due to previous late disruption)
plasma full length, 1MA, blips and a late H-mode (~1.4sec)
RF problems? D faulted out early, E ok. Prf<1MW total

Next: repeat?


May 31 2007 01:13:19:633PM1070531013Steve Wolfe
shot#13: repeat?
Delay for a camac problem, rebooting camac server cmodws34

May 31 2007 01:31:37:813PM1070531013Steve Wolfe
shot#13: repeat, hoping for rf and dnb
plasma. Still one short H-mode at 0.93sec. 
RF is worse,this time E faulted out and D stayed on. 
DNB ran ok

next: Try for better RF


May 31 2007 01:41:22:880PM1070531014Steve Wolfe
shot#14: repeat,  Try for better RF at slightly lower power
plasma full length
Nice EDA-ish H-mode (one of it!) starting around 1sec.
Only problem is the edge TS hi voltage got turned off when the
highways went down. 

Next: repeat with Thomson. No other (intentional) changes. 


May 31 2007 01:51:04:383PM1070531015Steve Wolfe
shot#15: repeat with Thomson. No other (intentional) changes. 
plasma full length, one long H-mode, looks good to me.

Next: decrease density


May 31 2007 02:12:50:300PM1070531016Steve Wolfe
shot#16: decrease density to 8e19
plasma full length, but three h-modes. 
RF stayed on nicely, last H-mode is more like EDA

next: drop nl04 to 6e19

May 31 2007 02:18:14:393PM1070531017Steve Wolfe
shot#17:  drop nl04 to 6e19
plasma, 3 h-modes, third one is most EDA-like

Next: Back to 600kA and 0.8e20

May 31 2007 02:34:32:587PM1070531018Steve Wolfe
Shot#18: Back to 600kA and 0.8e20; 
drop IC_EF4U back to 2000A

plasma full length, short EDA-like H-mode until ~1.1sec
RF fails later in pulse. 

Next: 1.2MA, 1.2e20

May 31 2007 03:04:50:803PM1070531019Steve Wolfe
Shot#19: 1.2MA, 1.2e20
Import seg2 from shot#11 and raise nl04 to 1.2e20
Delay to reset heater breaker. High TC reading?

Looks like there may be a runaway heater near C-port.
Cell access to investigate. 

May 31 2007 03:35:20:360PM1070531019Steve Wolfe
Shot#19: 1.2MA, 1.2e20
Import seg2 from shot#11 and raise nl04 to 1.2e20
Vessel went to -2C, long delay to chase down possible heater problem
which turned out to be an iced up tc cable. 
Base pressure down below .7e-6 so raise PG4 from 16 to 18msec
Load at 31-May-2007 15:21:51.00
to INIT at 15:30 (one hour delay)

plasma disrupted in rampdown 1.67sec, 750kA.
Hardly any RF. No H-mode. Maybe dithering near ohmic H-mode. 

Next: ?

May 31 2007 03:36:45:347PM1070531019Steve Wolfe
Shot#19: 1.2MA, 1.2e20
Import seg2 from shot#11 and raise nl04 to 1.2e20
Vessel went to -2C, long delay to chase down possible heater problem
which turned out to be an iced up tc cable. 
Base pressure down below .7e-6 so raise PG4 from 16 to 18msec
Load at 31-May-2007 15:21:51.00
to INIT at 15:30 (one hour delay)

plasma disrupted in rampdown 1.67sec, 750kA.
Hardly any RF. No H-mode. Maybe dithering near ohmic H-mode. 

Next: drop pg4 back to 16msec because of the disruption. 
Try again

May 31 2007 03:47:24:180PM1070531020Steve Wolfe
Shot#20: second go at 1.2MA, 1.2e20
 drop pg4 back to 16msec because of the disruption. 
Slow down rampdown clearin to try to prevent EF2's from 
going to zero, leading to rampdown disruption.

Fizzle. Moves in, probably didn't drop pg4 enough. 
Next: down another msec

May 31 2007 04:02:30:620PM1070531021Steve Wolfe
Shot#21: third go at 1.2MA, 1.2e20
 drop pg4 to 15msec 
 while I'm at it, slow down the RCUR rampin as well as the clearin, 
 but then change my mind and put it back. 

plasma full length, lots of H-modes, nothing steady. 
RF fair, probably not going to get a steady H-mode at this current.

Next: Back to lower current?
 



May 31 2007 04:15:08:783PM1070531022Steve Wolfe
Shot#22: Upper Null 1.2MA, 1.2e20 !
Go to seg3, copy over NL04, Ip, IC_EF4U, slow down CLEARIN ramp in 
rampdown. 
No startup changes. 

Plasma to 1.8sec, L-mode, marfe in rampdown. 
E port fine, Dport all faults. 

Next: drop nl04 to 1.0e20



May 31 2007 04:29:25:633PM1070531023Steve Wolfe
Shot#23: Upper Null 1.2MA, 1.0e20
Plasma disrupted at 1.2sec, full current disruption. 
No H-mode. Got RF at 1.6MW. 

Next: Reload shot 15 (1MA, 1e20 LSN)




May 31 2007 04:43:03:060PM1070531024Steve Wolfe
Shot#24: Import seg2 from 1070531015,
drop pg4 to 14 msec, best I can do to try to avoid the post-dis fizz

Fizzle. wouldn't quite make it. Almost.
Leave pg4 down and hope it's not too low this time. 




May 31 2007 04:56:17:377PM1070531025Steve Wolfe
Shot#25: Still trying to get back to 1.0MA, 1.0e20
PG4 still at 14msec (no changes)
plasma one H-mode not quite as nice as 15, some small back transitions?

Next: try for a repeat with different beam program


May 31 2007 05:06:12:803PM1070531026Steve Wolfe
Shot#26: Try for a repeat
PG4 from 14 to 15msec
fizzle. Try to get one more. 



May 31 2007 05:18:37:557PM1070531027Steve Wolfe
Shot#27: Trying to get background shot for 25
I think the best bet is just to repeat. #26 had
early breakdown 4.5ms, rising CIII, Halpha doesn't burn out,
then seems to go in; there was some current rise. 
No changes, cross fingers. 

Plasma full length. Looks very similar. 
Startup looks perfect. Chalk one more up to benign neglect. 

END OF RUN. 

Engineering Operator Comments
ShotTimeTypeStatusComment
109:47:38:227AMPlasmaBadEF1 Cap Bank Flt
210:08:58:783AMTestBadcap bank test
310:25:48:057AMTestOk
410:38:36:607AMPlasmaOk
510:58:24:960AMPlasmaOk
611:14:37:293AMPlasmaOk
711:33:03:253AMPlasmaOk
811:47:26:197AMPlasmaOk
912:03:43:967PMPlasmaOk
1012:18:34:990PMPlasmaOk
1112:31:12:807PMPlasmaOk
1212:44:11:763PMPlasmaOk
1301:22:21:280PMPlasmaOk
1401:35:41:580PMPlasmaOk
1501:48:44:507PMPlasmaOk
1602:01:19:683PMPlasmaOk
1702:14:28:300PMPlasmaOk
1802:27:46:320PMPlasmaOk
1903:30:17:453PMPlasmaOk
2003:42:59:600PMPlasmaOk
2103:56:08:887PMPlasmaOk
2204:10:13:110PMPlasmaOk
2304:24:19:177PMPlasmaOk
2404:37:22:260PMPlasmaOk
2504:50:04:187PMPlasmaOk
2605:02:29:567PMPlasmaOk
2705:14:54:477PMPlasmaOk

System Availability
May 31 2007 09:47:12:417AM
SystemAvailableCommentAvailability
Changed
OwnerDescriptionWho Can
Change
Active MHDyesFully operationalMar 28 2007 09:19PM (sears)Joe SnipesActive MHD Antennasears,snipes
BESyesvertical array of six views at R ~ 87.3 cm, radial array of three views out to R ~ 89 cm, both at outboard midplane. Three discrete fiber views of beam at R ~ 70.0, 76.5 and 82.5 cm.Feb 06 2007 10:00AM (bravenec)Ron BravenecBeam Emission Spectroscopybravenec
Bolometersyes2Pi diode operational, 2Pi foil being upgrade for noise resistance. Midplane foils calibrated for senstivity, still need better time constants. Midplane and divertor AXUV being digitized, processing calibration data.May 29 2007 11:22AM (mlreinke)Matt ReinkeBolometershutch,mlreinke
BoronizationyesFirst Boronization 5/9/07May 10 2007 04:55PM (irby)Jim IrbyBoronizationdekow,irby
CNPAno Jan 14 2007 02:06PM Ron ParkerCompact Neutral Analyzerparker
Cryopump - Upper DivertoryesThe cryopump is operational in a manual mode. We will be working on interfacing its control system with the C-Mod state machine for semi-automatic operation.May 30 2007 07:58PM (labombard)Brian LaBombardUpper Divertor Cryopumpirby,labombard
CXRSyesThe pedestal toroidal array was installed, spatially and absolutely calibrated. There are 10 chords intersect the beam at the major_R_range=[75,4:87.4]cm. Spatial resolution: 1.2 cm. The F-top poloidal array was installed and spatially calibrated. There are 19 chords intersect the beam at the major_R_range=[67.8:91.0]cm. Spatial resolution: 1.22 cm.May 01 2007 12:31PM (bespam)Bill RowanCharge Exchange Spectroscopybespam,blip,rachmcd,rowan
D Alphayes\ha2_bright and \SPECTROSCOPY::TOP.VUV.VIS_SIGNALS:MCP_VIS_SIG1 are availableMar 11 2007 10:28PM (terry)Jim TerryBalmer Alpha Monitorirby,terry,wolfe
Dalsayescamera is re-installed, and view has been calibratedFeb 26 2007 03:28PM (marmar)Earl MarmarVisible Bremsstrahlungmarmar
Disruption Mitigationno Jan 14 2007 02:02PM Bob GranetzGas Jetgranetz,whyte
Divertor IRno Mar 06 2007 10:50AM Glen WurdenDivertor IR Digital Videogwurden,terry
Divertor IR Spectroscopyno Mar 06 2007 10:51AM Glen WurdenDivertor IR Spectroscopygwurden,ldorf,terry
DNByesAll systems are operational, but as of 28 March 2007, the beam needs additional conditioning for full performance shotsMar 28 2007 09:36AM (beals)Bob GranetzDiagnostic Beambeals,granetz
FRC-ECEyesAll channels now working.Apr 04 2007 11:04AM (phillips)Perry PhillipsHeterodyne ECE-32 channelsphillips
G-Side RatiomaticyesThe gauge is operational.Mar 30 2007 10:54AM (labombard)Brian LaBombardG-side ratiomatic ionization gaugelabombard,toland
GPCyesChs 1-8 operational. May 24 2007 08:40AM (hubbard)Amanda HubbardECE Polychromaterhubbard,schmidt
GPC2yesMost channels (except 1,8,10,17) operational. Set to lower freqs for LHCD.May 24 2007 08:40AM (hubbard)Amanda HubbardECE Polychromaterhubbard,schmidt
GPIyesNew view just outside of the lower X-point is operational, but data is being archived locally , not to the tree. Midplane GPI is not operational.Mar 27 2007 01:59PM (terry)Jim TerryGas Puff Imagingterry,zweben
H/Dyesspectral calibration needs to be checked, but system should be ready for the runFeb 26 2007 03:28PM (marmar)Earl MarmarH/D Ratiomarmar
Hirex Jryes Mar 06 2007 08:59AM (rice)John RiceHigh Resolution X-Rayince,rice
Hirex SryesStoring Data, but profiles not yet availableApr 27 2007 01:20PM (ince)John RiceHigh Resolution X-Rayince,rice
HXRyesSomething might be wrong with channel 26; all others working fine.Mar 23 2007 10:43AM (schmidt)Ron ParkerHard X-Ray Arrayparker,schmidt
ICRF D-Antennayes80.5 MHz. readyMar 28 2007 08:50AM (ylin)Steve WukitchD-port antennawukitch,ylin
ICRF E-Antennano80 MHz. FFT installation/coaxial line needs more workMar 16 2007 09:32AM (ylin)Steve WukitchE-port antennawukitch,ylin
ICRF J-Antennayes78 MHzApr 04 2007 08:56AM (ylin)Steve WukitchJ-port antennawukitch,ylin
Lower Hybridno6B Pressure window failed. Arcing in 6B, 8B,9B & 23B. May 04 2007 03:44PM (dterry)Ron ParkerLower Hybriddterry,parker
LPIyes Apr 26 2007 08:35PM (bose)Earl MarmarLithium Pellet Injectorbose,marmar
Ly-alphayesMidplane data being digitized, processing calibration data. Divertor views showing significant noise, and not available. Upper view being debugged.May 29 2007 11:23AM (mlreinke)Matt ReinkeLyman alpha cameraslabombard,mlreinke
McPhersonyesWorking normally.Apr 19 2007 09:52AM (mlreinke)Jim TerryVUV Spectrometermlreinke,terry
MichelsonyesOperational. Mar 28 2007 08:33AM (hubbard)Amanda HubbardECE Te Profileshubbard,schmidt
MKSyesE-Top, E-Bottom, F-top (cryo), G-side, and B-bottom are operational. F-top gauge has a 'sniffer tube' to measure pressures in cryopump gas box.Mar 20 2007 06:42PM (g)Brian LaBombardBaratron pressure gaugeslabombard
MLPnoInitial tests on the A-port scanning probe went well. We need to take care of some control glitches that caused some component failures. May 30 2007 08:01PM (labombard)Brian LaBombardMirror Langmuir Probe Electronics Systemlabombard
MSEno(1) Bandpass filters replacement underway (2) Beam-into-gas spectrum measurement underway (3) Shutter mechanism currently unstable; remains open. (4) Expect beam-into-gas calibrations complete about 4/24. Apr 03 2007 12:05PM (sscott)Steve ScottMotional Stark Effectjinseok,sscott
NeutronsyesBoth neutron systems are fully operationalApr 05 2007 11:19AM (fiore)Catherine FioreNeutron Detectorsfiore
Neuts and HardsyesoperationalMar 21 2007 04:29PM (irby)Jim IrbyX-Ray/Neutron Detector at K-Horirby
NINJAyesAll capillaries displayed by the NINJA_CONTROL GUI have been tested. NINJA puffed on 1070329009 (A-B limiter).Mar 29 2007 11:47AM (terry)Brian LaBombardNINJA gas pufflabombard,terry
PCIyesThe system is to be optimized.May 30 2007 01:12PM (lianglin)Miklos PorkolabPhase Contrast Imagingedlund,lianglin,ntsujii,porkolab
Penning Gaugesyes8 in-situ Penning ionization gauges appear to be operational: CB_DivU, CB_OutL, CB_DivL, KA_OutU, KA_OutL, B_DivL, Cryo_1, Cryo_2. Cryo_1 and Cryo_2 are new and installed in the upper cryopump 'gas-box'.Mar 13 2007 10:01PM (labombard)Brian LaBombardPenning Ionization Gaugeslabombard
Plasma TVyesWIDE1, WIDE2 (chan 33), DANT, JANT and DIV (without an ND filter) are operational.Mar 27 2007 01:53PM (terry)Jim TerryVideo of plasma via several camerasdekow,irby,terry,wolfe
PolarimeternoRetro shutter closedMar 15 2007 11:00AM (irby)Jim IrbyC-Mod Polarimeterirby
Probe Array - ISDyesProbes at 15 of the 16 poloidal locations ('ramped' geometry) are operational. n,Te, particle flux reported every 10 ms.Mar 13 2007 09:47PM (labombard)Brian LabombardInner Lower Divertor Probe Arraylabombard
Probe Array - LHyesAll 6 probes on the lower hybrid launcher (tungsten, 1.5 mm projection) are operational. Mar 13 2007 09:46PM (labombard)Brian LaBombardLower Hybrid Probe Arraylabombard
Probe Array - OSDyesProbes at 10 poloidal locations (one 'ramped' and one 'flush') are operational. n,Te, particle flux reported every 10 ms. Mar 13 2007 09:45PM (labombard)Brian LaBombardOuter Lower Divertor Probe Arraylabombard
Probe Array - UDIVyes14 probes are operational ('ramped' geometry). n,Te, particle flux reported every 10 ms.Two high-gain channels are installed and operational for ECDC plasma diagnosis.Mar 13 2007 12:46PM (labombard)Brian LaBombardUpper Divertor Probe Arraylabombard
ReflectometernoAll fixed channels are disconnected, the variable frequency channel is being tested. Starting 1070529, the Waveform signal has a 1/2 voltage divider. On 1070530, I'll be testing the 1/2 divider: Shot 14 is set at 1.5V and starting shot 15 is set at 6VMay 30 2007 12:44PM (dominguez)Earl MarmarReflectometerdominguez,marmar
Scanning Probe - ASPyesPerpendicular Mach probe head is installed. The drive is operational.Mar 15 2007 09:09PM (labombard)Brian LaBombardA-Port Scanning Probelabombard
Scanning Probe - FSPyesPerpendicular Mach probe head is installed. The probe drive is now operational.Mar 13 2007 09:51PM (labombard)Brian LaBombardF-Port Scanning Probelabombard
Scanning Probe - WASPyesA-port WASP successfully collected data on 04/04. Some intermittent open circuit on SE Electrode. K-WASP took data on 04/11. Both ready to scan as needed.Apr 12 2007 04:18PM (nsmick)Brian LaBombardInner Wall Scanning Probelabombard,nsmick
TCIyesNL_04 at 71.04 cm from 3/9/07 calibrationMay 23 2007 07:38AM (irby)Jim IrbyTwo-Color Interferometerirby,murray
TS - Coreyes2 lasers, 11 spatial channels. Density is calibrated based on ECE cutoffs obtained on 4 May 2007. Additional spatial channels will be added over the next several weeks.May 10 2007 10:37AM (jwhughes)Jerry HughesCore Thomson scatteringjwhughes
TS - Edgeyes2 lasers, 20 spatial channels. Fiber holder position is -125mm (standard). Density is cross-calibrated to the core system, based on shots 1070504014, 016, and 019.May 21 2007 02:39PM (jwhughes)Jerry HughesMillimeter resolution edge Thomson scatteringjwhughes
Vispecyes350 and 670 nm, 4 spatial channelsMay 04 2007 01:02PM (agraf)Alex GrafVisible Spectrometeragraf