Alcator C-Mod Run 1120816 Information

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Miniproposals
Miniproposal:715
Date Filed: 7/21/2012
Title:Do current ramps modify H-mode access?
First Author:Jerry Hughes
Session Leader:Jerry Hughes (shots 17-24)
Miniproposal:716
Date Filed: 7/21/2012
Title:ITER demo discharge studies at 5.4T
First Author:Steve Wolfe
Session Leader:Steve Wolfe (shots 1-16)

Operators
Session leader(s):Steve Wolfe,Jerry Hughes
Physics operator(s):Steve Wukitch
Engineering operator(s):Bill Parkin,Roza Tesfaye,Ed Fitzgerald

Engineering Operator Run Comment
MP#716 ITER Demo discharges at 5.4T

Session Leader Plans
Entered: Aug 16 2012 12:42:46:967AM
Author: Jerry Hughes

If time is made available for MP715 tomorrow, the shot plan will consist of:

1. Load from 1120810030.

Load ICRF demand from 1120810030, and make the following changes:
0.5--0.7s: keep unchanged
0.7--0.8s: increase by 300kW
0.8--1.0s: keep unchanged
1.0--1.1s: decrease by 300kW
1.1--1.3s: keep unchanged
1.3--1.5s: increase by 300kW

Disable NINJA.
Enable Ar from B-side lower. Use a 70ms puff at 0.3s. Keep this constant
throughout.

Make any necessary adjustments to ECE to reproduce coverage from previous
runs of this MP on 1120807 and 1120810.

Run this shot and look for L-H transitions.

2. Adjust the Prf steps shot-to-shot in order to resolve the power threshold in
each phase.

3. In the unlikely event that step 2 is completed, then change the order of
current ramps to rule out time-sensitive behavior:

Change the current demand so that:
0.5--0.7s: flat 1.1MA
0.7--0.8s: ramp from 1.1 to 0.8MA
0.8--1.0s: flat 0.8MA
1.0--1.1s: ramp from 0.8 to 1.1MA
1.1--1.3s: flat 1.1MA
1.3--1.5s: ramp from 1.1 to 0.8MA
1.5-- : ramp down as usual

Adjust Prf steps to attempt to stay below Pth based on experience in 2.
Then re-adjust to check Pth in each phase.



Entered: Aug 16 2012 08:27:25:097AM
Author: Steve Wolfe
Session Leader plan for Thursday, Aug 16, 2012
MP#716 ITER Demo discharges at 5.4T
SL: wolfe

Overnight boronization required (standard prescription, He ECDC afterward)

Required systems:
---------------- 
ICRF (all 4 transmitters)
LH (700kW or max available power)
N2 seeding (16psi in H-bottom plenum), enable B-div-horizontal output PG6
Argon (1psi in B-side Lower) 

Diagnostics:
------------
All standard profile diagnostics should be operational. Thomson
scattering views should be arranged to cover the pedestal in the 
ITER shape (ref 1120807012). HIREX_SR data for Ti and rotation is
desired, provided it does not require too much argon. Neutron rate 
measurements are required. Core bolometry (Prad_Main) is required. 
Divertor bolometry is desired. Nitrogen monitoring as on 1120807 is
desired. Divertor heat flux measurements, including IR camera, are 
desired.  
Fluctuation diagnostics are desired and encouraged. 
Non-perturbative NINJA puffing for GPI will be allowed. 
LHRF-related diagnostics should be enabled (no need for HXR though)
We'll be doing N2 puffing, so the B CXRS systems will presumably not
be useful.  

Run begins at 09:00 and ends at 14:00 (assuming no delays)
This MP will end by 13:00 (or earlier), 
to be followed by one hour (or more) of MP#715, assuming Jerry wants it. 

The goal of this run is to extend the C-Mod dataset of ITER-like discharges
employing EDA H-modes to 5.4T, 1.3MA, kappa=1.75, q95~3.2. The target 
performance, as defined in IOS-1.1, is to achieve beta_N>1.7, which 
corresponds to Wmhd>300kJ; this would significantly exceed the record stored 
energy for C-Mod, and implies H98~1. It's good to have goals. 

This run will build on the experience from MP645a on 1120807, and try to
improve the beta, primarily by increasing the confinement. The best results
from 1120807 had H98~0.7 and beta_N~1.2. Steady EDA H-modes were obtained 
with nebar~5.2e20, n/nG~0.6. Pnet/Pth was below 1, which may account for
the low H factor. There is essentially no headroom on the RF power, which 
ran up to 4.5MW, but it may be possible to increase Pnet somewhat by 
reducing the core radiation further. We may also be able to reduce the
H-mode density and perhaps increase the confinement by adding LH power,
as in Matt's MP701 experiment on 1120725, which found surprisingly 
beneficial effects from 650kW of LH at quite high density. 

We will start from shot#1120807018 (target nl04=1.6e20, N2 seeding
at 40%) but extend the flattop from 
1.2 to 1.5sec, keeping the RF power flat at 4.5MW (or maximum) to 
EOF. The N2 seeding puff will also be extended. The idea is to see if 
the core radiation will decrease further, as observed in other seeded
EDA H-modes. It may be useful to decrease the outer gap to improve
the RF loading to keep J from faulting near its voltage limit. It 
may also be useful to reduce the initial RF power to 2MW to avoid ELM-free 
behavior in the early H-mode. 

We will then add LH power in the 600 to 700kW range, and see if the magic
observed on 1120725 translates to the even higher densities of 
the ITER-like case. 

There are a limited number of knobs available, so if these are not 
successful we may be ready to bail out early. Jerry has at least
another hour allocated to MP#715, and we could add any time saved from
MP#716 to that. 

Proposed shot sequence (total 15 shots):

1) Boronization recovery and shot setup [3-6 shots]
Load from 1120807018 (both seg1 and 2), extend flattop (including Ip and 
shape programming) from 1.2 to 1.5sec. Extend TF to 1.7 sec. 
Enable B-div (N2) as in the reference shot, with puff extended to 1.3sec.
Probably want some changes to early PCS programming to try to avoid the
vertical thrashes between 0.8 and .14 sec encountered on 1120807 (tbd).   
RF programmed to start at 0.6sec, 2MW, and ramp to 3MW at 1.2sec, 
then flat at 3MW to EOF, then drop to 1MW in rampdown. 
a) Begin boronization recovery, increasing the max RF power to 4.5MW. 
Adjust outer gap if  necessary to improve RF loading.
b) Once EDA H-mode is established, inject minimum amount of argon (B-side Lower) 
consistent with usable HIREX_SR signal; start with 35msec (@1psi).
If it seems to adversely affect the EDA then turn it off. 
c) Once H-mode is obtained, begin injecting LH between .9 and 1.2 sec (or 
at some time during the EDA). If necessary, adjust outer gap to improve LH
coupling, hopefully without compromising ICRF.  Raise power to ~700kW, if
possible. 

2a) If LH seems to be effective, either in improving H or decreasing pedestal
density, extend pulse length to cover more of the flattop. If possible, 
increase LH power. Tune for most neuts. [2-5 shots]

2b) If LH won't couple or has no effect, then turn it off. 
Try tailoring RF power and seeding waveforms to maximize performance in
quasi-steady EDA. [2-5 shots]

3) Density scan:
a) If previous steps have been successful in increasing Wmhd into the target
range, then increase the target density to probe the effect of increasing
n/nG. Based on the results of MP#698, we expect degradation of the H-factor,
and the RF may be adversely affected by increased fueling, so there is
probably not a lot of room for a scan in this direction [2-3 shots]
b) If we haven't been successful in step 2, then decrease the target 
density and see what can be done in more transient, ELM-free conditions. 
Target nl04=1.2e20 and 1.0e20; try increasing the N2 seeding to avoid 
overheating the divertor and excess Mo. [3-5 shots] 

4) If we haven't turned off the argon, and the results look sufficiently
interesting, then run a locked mode shot so HIREX_SR can calibrate its 
rotation measurements. 



Physics Operators Plans
Entered: Aug 16 2012 06:32:54:890AM
Author: Steve Wukitch
-----------------
Engineering Setup
-----------------

Run begins at 09:00 and ends at 17:00
MP#716 ITER Demo discharges at 5.4T
SL: wolfe
PO: Wukitch

First Half of Run
=================

Power systems as on: 1120807018

Acoil: +Dtop -Dbot -Jtop +Jbot (standard) Hybrid Enabled

Gas setup:

Require N2 bottle connected
Pump and purge all plenums (except B-side Upper)
Fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid DISABLED (PG1)
leave B-side upper as is Hybrid DISABLED (PG2)
fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3)
fill H-bot with 16psi of N2, Hybrid DISABLED (PG6)
fill NINJA with 10 psi D2 DISABLED


Enable gate-valves and shutters: ECE, VUV, HiREX Sr, Xeus/LoWEUS
Leave z-bolo shutter as is (should be open)

Torvac gatevalve toggle (yes/no): no

Boronization(yes/no): yes
Overnight ECDC (yes/no): Yes
ICRF(yes/no): Yes
LH(yes/no): no
Cryopump (yes/no): no
DNB (yes/no): no

Vessel temperature: 35/35/35

--------------------------------------
Boronization Parameters (if requested)
--------------------------------------
rmin/rdwell/rmax: 44/75/90 cm
tdwell/tsweep: 60/120 s

EF4 current: 0 A

----------------------------
Post boronization ECDC
----------------------------
1st Gas Setup:
Gas: He
sweep: 45/103/45 cm
scan: 20/120 s
Pressure: 5e-5 Torr
Duration: 2Hrs

----------------------------
PO Plan
----------------------------

Made changes to avoid thrash at segment switch (0.08 s)
EF2U was copied from EF2L
ZXL was zeroed before 0.5 s
We did not modify RCUR gains which also have discontinuity at the segment switch

Increased the flat top to 1.5 s from 1.2 s
Ip turns over at 1.5 s
nl_04 extended to 1.5 s
RCUR extended to 1.5 s

follow SL plan

Session Leader Summaries
Entered: Aug 16 2012 02:05:25:710PM
Author: Steve Wolfe
Session Leader summary for 16-aug-2012, 9:00-13:00
MP#716: ITER demo discharges at 5.4T
SL: wolfe
PO: wukitch
EO: Parkin, Tefaye

We gave it the old Institure try, but we were unsuccessful 
in increasing the beta_N of the 1.3MA, nebar~5e20/m^3 H-mode
discharge above 220kJ, betaN~1.15, which had already been achieved
on 1120807. 

The LH was unsuccessful operating above 200kW of net power, and
any effect on the discharge was hard to see. 

ICRF coupled up to 4MW with only a few faults. 

The H-modes for the first part of the day were much more ELM-free
than expected, based on the results of 1120807. After shot#9 we turned
on the H-div puff, at the same ~10Tl/sec as B-div, and we got 
steadier radiated power, and longer EDA-ish H-modes with small ELMs,
but low pedestals and somewhat poorer H-factor and beta. These shots also
used delayed ICRF (to .7sec rathere than .6), so it's not completely
clear what killed the ELM-free behavior, but I think it was the incresed N2. 
Attempts to reduce the total N2 puff on shots 14-16 were frustrated by fizzles. 

The best H-mode shots in terms of steady Prad and beta were 10,11 and 13.
These shots also had small ELMs, and very quasi QCM. Jerry reports
that the pedestal density was high, nearly up to the central density,
which has previously been flagged as not being conducive to good 
H-factors. H98 was about 0.6, i.e. L-modish, on these shots, somewhat
higher on the ELM-freeish cases earlier in the day, e.g. H98 > 0.7 on 
shot#4 and 5, but still not nearly good enough. 

JT got IR camera data on the high N2 shots, which indicated very low
power to the outboard divertor, which is consistent with the display_energy
plots. I need a probe person to look at the probe data, but it looked 
to me like the outer divertor detached on these, which is different
from the results with half the total N2 on 1120807. Core N2 signals
were about higher than shots earlier in the day, and roughly flat during
the H-mode. Probably the core radiation was dominated by low-z, since the
Mo brightness went way down. There may be some additional data for the 
seeding study in today's shots; nothing really to contribute to IOS-1.1. 



Entered: Aug 16 2012 04:50:42:663PM
Author: Jerry Hughes
MP715 wrap-up. (PM run)

We had an apparently successful ~2 hours devoted to finishing
MP715. This comprised shots 17--24. Seven of these were useful
plasmas, intended to be similar to discharges developed for run
1120810.

Shots 17--20, 22 and 23 had Ip waggles during flattop, and varying
steps of ICRF power. Short-lived H-modes were obtained in several
cases, and we were able to bracket the power threshold with d|Ip|/dt =
+/-3MA/s, and also with a half-speed ramp-up. Shot 24 was a constant
Ip=0.93 flattop with RF power steps to establish the control power
threshold. The L-mode density in all cases ranged from about 1.9 to
2.6 x 10^20 m-3.

With non-ramping current, 1.1MW of ICRF was required to initiate
H-mode. When ramping |Ip| down, only about 0.7MW of ICRF was
required. This reduction is consistent with initial results obtained
for this MP on 1120810. When ramping |Ip| up, we needed closer to to
2.0MW of ICRF power. This is all on top of ~1MW of Ohmic power, give
or take.

I want to check my ohmic power calculation and include the
Wdot before saying anything about the total power at L-H in all these
cases.



Physics Operator Summaries
Entered: Aug 16 2012 03:09:24:570PM
Author: Steve Wukitch
We had concerns about instabilities at segment 1 to segment 2 switch
but we did not have it today. We made changes prior to operation to
avoid discontinuities. In particular, EF2U was copied from EF2L and
the chopper was zeroed at 0.05 s. We had more fizzles than we would
like and to control the moly radiation we increased N2 seeding. The
second part of the run went smoothly and was based on 1120810 with
largely RF waveform modifications.

Summary

plasmas 17
fizzle 7
disrupted 3 (>0.7 MA)
---------------------
attempts 24

Session Leader Comments
Aug 16 2012 08:45:04:753AM1120816001Steve Wolfe
There was a snafu on the cooling water temperature last night,
and a number of HV systems have water condensation issues this 
morning. RF and power systems engineers are trying to get things 
dried out. 

Shot#1: First plasma attempt, aiming for 1.3MA to 1.5sec eof, 
target nl04=1.6e20; may have first shot after boronization wall
outgassing issues. RF should fire 2-> 3MW, starting at 0.6sec. 
N2 seeding requested from 0.55sec to 1.3sec (40% on B-DIV)
No LH on first shot. 

Aug 16 2012 09:17:49:387AM1120816001Steve Wolfe
There was a snafu on the cooling water temperature last night,
and a number of HV systems have water condensation issues this 
morning. RF and power systems engineers are trying to get things 
dried out. 

Shot#1: First plasma attempt, aiming for 1.3MA to 1.5sec eof, 
target nl04=1.6e20; may have first shot after boronization wall
outgassing issues. RF should fire 2-> 3MW, starting at 0.6sec. 
N2 seeding requested from 0.55sec to 1.3sec (40% on B-DIV)
No LH on first shot. 

Result: plasma disrupted 1.6 sec, with H-modes
Going vertically unstable in late flattop. 
RF on and off. Wmhd maxes out at 160kJ

Need to look at the vertical instability
ECE turbo tripped on the disruption,
engineer's workstation crashed. 




Aug 16 2012 09:41:45:450AM1120816002Steve Wolfe
Shot#2: tweaked the late flattop and rampdown a little,
hopefully RF will stay on better. 

Result: presure was 6e-6 in Check? 
fizzle. pressure was .07mTorr at breakdown.
Probably a gatevalve opened at high pressure in init or check. 

Next: repeat, after cell access for JT, TCI, etc



Aug 16 2012 09:57:52:017AM1120816003Steve Wolfe
Shot#3: repeat, after cell access for JT, TCI, etc

plasma to 1.8sec
lots of h-modes again, lots of rf faults. 
Max wmhd=187kj, very transient
Early H-modes look pretty elm-free, 

Repeat, try for better RF
hold off on lh for now. 



Aug 16 2012 10:13:45:220AM1120816004Steve Wolfe
Shot#4:Repeat, try for better RF
hold off on lh for now.

plasma to 1.8sec, despite a high pressure in check from VUV (McPherson)
three H-modes, all pretty ELM-free? Target density is 1.65e20 
at the first one, but radiated power is screaming up. 
Wmhd reaches 210kJ, betaN~1.18
RF better, trips on H-L I think. 

Next: 
Request LH from 0.9 to 1.2sec, 
raise target nl04 to 1.7e20
raise icrf flattop power to 4MW
Increase pg6 from 40 to 50%, only got 6.6T-l in .75sec, try a little more


Aug 16 2012 10:28:38:463AM1120816005Steve Wolfe
Shot#5 :Request LH from 0.9 to 1.2sec, 
raise target nl04 to 1.7e20
raise icrf flattop power to 4MW
Increase pg6 to 50%
VUV gate valve off, I hope. 

plasma to 1.7, too many h-modes
J-port drops out in the middle of the shot
LH faulting repeatedly.
Wmhd transiently to 207 in first h-mode.  
H98~.7

Move LH earlier, .75-1.0sec
RF still tuning. 
Move start of pg6 to 0.5sec


Aug 16 2012 10:46:21:737AM1120816006Steve Wolfe
Shot#6 :Move LH earlier, .75-1.0sec
RF still tuning. 
Move start of pg6 to 0.5sec

Disrupted at 1.35sec, one H-mode until it dies,
or maybe it just restrike quickly? 
nebar~6e20, wmhd~210kJ
Some rf faulting, but not too bad, max rf~4MW. 
Prad still high, looks like Mo? 
LH a little better, continuing to try. 

Next: try again



Aug 16 2012 10:59:23:297AM1120816007Steve Wolfe
Shot#7 : try again

plasma full length, 
lots of transitions, 
lots of faulting on ICRF, lost D at 1.2sec,
faulting on E and J. 
LH is looking a little better at 200kW, no 
obvious effect.

Next: Enable H-div puff same as B-div, should almost 
double the N2, which would be too much based on last week,
but it's not doing much now. 



Aug 16 2012 11:07:04:220AM1120816008Steve Wolfe
Shot#8: Enable H-div puff same as B-div, should almost 
double the N2, which would be too much based on last week,
but it's not doing much now. 

fizzle, looks like a flake at .03 sec or so, moving outside. 
Cell access to fix ratiomatic. Also engineers will check fuses in OH1

Next: repeat

Aug 16 2012 11:34:01:643AM1120816009Steve Wolfe
Shot#9: Enable H-div puff same as B-div, should almost 
double the N2, which would be too much based on last week,
but it's not doing much now. 

plasma full length. Steady Prad from 1.0 to 1.5sec
Steadier H-mode at ~200kJ, D faults out after 1.2sec or so. 
LH stays on pretty well at 200kW, but it's only there before 1sec
ECE is right on the edge of cut-off. N light is up, Mo seems to be 
down, except for a spike around 1.1sec
If I'm interpreting the probes correctly, we may be detaching the 
outer div. 

Add 2mm to outer gap for LH
Delay ICRF to .7, delay LH to .85 and run to 1.3sec



Aug 16 2012 11:38:02:267AM1120816009Steve Wolfe
Shot#9: Enable H-div puff same as B-div, should almost 
double the N2, which would be too much based on last week,
but it's not doing much now. 

plasma full length. Steady Prad from 1.0 to 1.5sec
Steadier H-mode at ~200kJ, D faults out after 1.2sec or so. 
LH stays on pretty well at 200kW, but it's only there before 1sec
ECE is right on the edge of cut-off. N light is up, Mo seems to be 
down, except for a spike around 1.1sec
If I'm interpreting the probes correctly, we may be detaching the 
outer div. 
Ratiomatic is back on, but calibration looks high by at least 
a factor of two

Add 2mm to outer gap for LH
Delay ICRF to .7, delay LH to .85 and run to 1.3sec
Ask JT to turn on IR camera, it's been off!


Aug 16 2012 11:56:13:747AM1120816010Steve Wolfe

Shot#10: Add 2mm to outer gap for LH
Delay ICRF to .7, delay LH to .85 and run to 1.3sec
Ask JT to turn on IR camera, it's been off!

plasma to 1.8sec, steadier Prad around 2MW, 
RF looks good, LH timing was not changed, 
Wmhd is down to 190kJ, nebar~5.4e20. 
JT reports very low power on outer divertor, consistent with TC's

Next: get ICRF to 4MW by 1.0sec, 
LH extended to .85 to 1.3sec, step power up to 450 for second half



Aug 16 2012 12:06:06:343PM1120816011Steve Wolfe

Shot#10: get ICRF to 4MW by 1.0sec, 
LH extended to .85 to 1.3sec, step power up to 450 for second half

Similar shot, a few more rf faults, prad pretty steady
LH ok at 240kW, faults at 450; not looking good for increasing that. 
wmhd peaks at 195kJ, then falls.Elongation up a bit
D is not happy at the end of flattop.  

LH will try more smaller steps. 




Aug 16 2012 12:13:10:090PM1120816012Steve Wolfe

Shot#12:LH will try more smaller steps.
Fizzle, injection at .035sec 

Next: Try again





Aug 16 2012 12:41:22:080PM1120816013Steve Wolfe

Shot#13:LH will try more smaller steps.
Fizzle, injection at .035sec 

Disrupts in early rampdown, long steady-ish H-mode, 
still decaying stored energy and neutrons. 
LH is no better, still nothing above 220kW.
There may be a problem with nl04 analyzed data on this shot,
the feedback signal shows target at 1.65e20, analyzed signal says over 2.
 

Move plasma over in by 2mm, trying to improve LH 
Decrease N2 puffs to 35%. 




Aug 16 2012 12:41:52:333PM1120816014Steve Wolfe
Shot#14:Move plasma over in by 2mm, trying to improve LH 
Decrease N2 puffs to 35%. 

fizzle, hits outside, so dropping the fill would have made it worse.
Try again. 


Aug 16 2012 12:57:07:987PM1120816015Steve Wolfe
Shot#15:Move plasma in by 2mm from #13, trying to improve LH 
Decrease N2 puffs to 35%. 

Another fizzle, 

One more try, then turn it over to Jerry,
unless something really exciting happens.

Aug 16 2012 01:03:16:943PM1120816016Steve Wolfe
Shot#15:Move plasma in by 2mm from #13, trying to improve LH 
Decrease N2 puffs to 35%. 
One more try, then turn it over to Jerry. 

Fizzle, that's all for this one. 

Aug 16 2012 01:27:06:707PM1120816017Jerry HughesTime to squeeze some more juice out of MP715.

Shot 17

Try a reload of 1120810030, with some mods to the RF power program.

Result: Good Ip trace.
900kW in the flat Ip periods. 2nd one has some faults.
1200kW in the fast ramp-up phase with some faults.
560kW in the ramp-down phase clean.
1200kW in the slow ramp-up phase clean.

No L-H in any case.

Next try to get cleaner RF, plus more demand in some phases.

Aug 16 2012 01:47:19:457PM1120816018Jerry HughesShot 18:

Result

1st flat Ip phase: no L-H with 900kW clean
fast ramp up: no L-H with 1200kW (fault)
2nd flat Ip phase: no L-H with 900kW clean
fast ramp down: L-H at 1.057s, with Prf=750kW, clean
3rd flat Ip phase: no L-H with 900kW (faulting) -- but we are limited because of
an uncorrected radial excursion.
slow Ip ramp-up: no L-H with 1500kW (one fault, partly limited)

This would seem to bracket the power needed in ramp-down phase.

Next: adjust power levels further to try find L-H in other phases.
Aug 16 2012 01:55:53:377PM1120816019Jerry HughesShot 19:

Result

1st flat Ip phase: no L-H with 900kW clean
fast ramp up: no L-H with 1700kW (fault late)
2nd flat Ip phase: no L-H with 1050kW clean
fast ramp down: no L-H, with Prf=650kW, clean
3rd flat Ip phase: no L-H with 900kW (faulting)
slow Ip ramp-up: no L-H with 1650kW (some faulting)

Need to be more aggressive with power, given the time available

Aug 16 2012 02:05:27:493PM1120816020Jerry HughesShot 20:

Result:

1st flat Ip phase: no L-H with 1200kW (fault)
fast ramp up: no L-H (I think) with 1950kW (faults, with a skrinking RGAP)
2nd flat Ip phase: no L-H with 1370kW clean
fast ramp down: L-H at 1.03s, with 950kW, clean
3rd flat Ip phase: no L-H with max 1170kW (faulting)
slow Ip ramp-up: no L-H with 1950kW (some faulting)

Next: Raise power 400kW in the ramp-up phases and 300kW in the flat Ip phases.
Drop power 100kW in the ramp-down phase.
Aug 16 2012 02:09:20:880PM1120816021Jerry HughesShot 21

Fizzle


Aug 16 2012 02:35:56:680PM1120816022Jerry HughesShot 22

Nice shot. 3 H-modes.

Result:
Good RGAP, good density trace

1st flat Ip phase: no L-H with 1200kW (fault)
fast ramp up: L-H at 0.724s with 2000kW, clean (but just barely into the ramp-up)
2nd flat Ip phase: no L-H with 1430kW clean (recovering from H-L transition)
fast ramp down: L-H at 1.04s, with 800kW, clean
3rd flat Ip phase: no L-H with max 1200kW clean (recovering from H-L transition)
slow Ip ramp-up: L-H at 1.46s with 1950kW clean

Next: Adjust power some more to clean up result
Aug 16 2012 02:49:37:203PM1120816023Jerry HughesShot 23

Good shot. Clear transition in the fast ramp-up phase.

1st flat Ip phase: no L-H with 1000kW, clean
fast ramp up: L-H at 0.76s with 2080kW, mostly clean
2nd flat Ip phase: no L-H with 1430kW clean (recovering from H-L transition)
fast ramp down: L-H at 1.05s, with 650kW clean
3rd flat Ip phase: no L-H with max 1400kW, mostly clean (recovering from H-L transition)
slow Ip ramp-up: no L-H with 1760kW clean

Still need a clear Pth result with constant Ip.
Aug 16 2012 03:08:14:197PM1120816024Jerry HughesShot 24

Constant Ip plasma, with RF steps.

Perfect. L-H at 0.85s with 1120kW ICRF.

That nails it. We have bracketed the threshold power in the flat Ip case as
well as in the Ip ramps.




Physics Operator Comments
Aug 16 2012 09:02:35:120AM1120816001Steve Wukitchprep for 001

Seg2:
Move ramp in on RCUR to start at 1.5sec, instead of 1.35sec (your logbook
entry says you did this, but it doesn't seem to have happened)
Move ramp in on CLEARIN to start at 1.5sec, instead of 1.2sec
On ALL_V's screen:
extend TF flattop to 1.7sec (from 1.5sec) for ICRF heating in rampdown.
extend B-divertor (PulseGas6) pulse to 1.3sec (from 1.0sec)
Seg1:
On ALL_V's screen: Change Chopper waveform to get down to 0.0 at .05sec (was
at .06)

We will want B-divertor gas enabled for first shot.

Aug 16 2012 09:34:10:447AM1120816001Steve Wukitch001 demand: nl04~1.6, BT~5.4, Ip~1.3

result: plasma disruption in rampdown - vertically unstable
next: extend ZXU into rampdown (1.65 s)
modify ZXL during rampdown
Load at 16-Aug-2012 09:33:18.00

Aug 16 2012 09:42:04:937AM1120816002Steve Wukitch002 demand: nl04~1.6, BT~5.4, Ip~1.3
result: fizzle - pressure spike observed in check
checked vacuum behind diagnostics - look okay
next: return prepuff to 20 ms
Load at 16-Aug-2012 09:40:26.00

Aug 16 2012 10:13:45:397AM1120816003Steve Wukitch003 demand: nl04~1.6, BT~5.4, Ip~1.3
result: plasma - disrupted about ~0.5 MA
multiple H-modes

next: slow decrease in RCUR during rampdown
Load at 16-Aug-2012 09:59:07.00

Aug 16 2012 10:14:40:783AM1120816004Steve Wukitch004 demand: nl04~1.6, BT~5.4, Ip~1.3
result: plasma despite VUV/HIREX SR - McPherson opening and raising the Torus pressure
H-modes are ELM free
next: raise target density to 1.7, raise demand at 0.3 s to 1.4
raise RF power to 4 MW
start LH injection
slow ZXU ramp in rampdown
Load at 16-Aug-2012 10:13:22.00

Aug 16 2012 10:59:31:270AM1120816007Steve Wukitch007 demand: nl04~1.7, BT~5.4, Ip~1.3
result: plasma - further into rampdown
LH ran better
ICRF was ratty
next: prepuff back to 20 ms
H-div enabled
Load at 16-Aug-2012 10:58:04.00

Aug 16 2012 11:12:03:880AM1120816008Steve Wukitch008 demand: nl04~1.7, BT~5.4, Ip~1.3
result: strong fizzle - ill time crudflake at 0.03 s

next: repeat
cell access to replace filament - f-side ratiomatic
Aug 16 2012 11:51:49:003AM1120816010Steve Wukitch010 demand: nl04~1.7, BT~5.4, Ip~1.3
result: plasma
best RF of the day thus far
next: repeat with adjusted LH and ICRF timing/power level

Aug 16 2012 12:06:24:873PM1120816011Steve Wukitch011 demand: nl04~1.7, BT~5.4, Ip~1.3
result: plasma

next: repeat with different LH

Aug 16 2012 12:18:02:857PM1120816012Steve Wukitch012 demand: nl04~1.7, BT~5.4, Ip~1.3
result: fizzle - ill timed crudflake at 0.03

next: make EF4 more positive by 10 A (-1310 to -1300)
work on rampdown - limit plasma more quickly by reducing CLEARIN at 1.8 s
Load at 16-Aug-2012 12:17:35.00

Aug 16 2012 12:44:27:760PM1120816013Steve Wukitch013 demand: nl04~1.7, BT~5.4, Ip~1.3
result: plasma - disruption in rampdown

next: move whole plasma away for LH
reduce RCUR by 2 mm
reduce CLEARIN by 2 mm
Load at 16-Aug-2012 12:33:15.00

Aug 16 2012 12:49:32:550PM1120816014Steve Wukitch014 demand: nl04~1.7, BT~5.4, Ip~1.3
result: fizzle - hits on outboard

next: raise prepuff 2 ms to 22 ms
PG6 and PG7 at 35V
Load at 16-Aug-2012 12:47:57.00

Aug 16 2012 12:55:30:243PM1120816015Steve Wukitch015 demand: nl04~1.7, BT~5.4, Ip~1.3
result: operator error - did not increase prepuff as I intended

next: increase prepuff 3 ms
Load at 16-Aug-2012 12:54:10.00

Aug 16 2012 01:04:33:177PM1120816016Steve Wukitchfizzle
Aug 16 2012 01:05:00:007PM1120816016Steve WukitchPower systems same as 1120810030.

Aug 16 2012 01:12:39:867PM1120816016Steve Wukitchnext: loaded from 1120810030 both seg1 and seg2
only changes are RF waveforms
Load at 16-Aug-2012 13:11:44.00

Aug 16 2012 01:23:22:530PM1120816017Steve Wukitch017 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma

next: adjust RCUR to avoid outboard contact at 1.2 s
Load at 16-Aug-2012 13:20:28.00

Aug 16 2012 01:38:09:160PM1120816018Steve Wukitch018 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma
right gap is too small from 1.1-1.4 s
next: increase right gap - RCUR smaller by 0.01
increase nl_04 demand at 0.24 s to 1.2
Load at 16-Aug-2012 13:37:09.00

Aug 16 2012 01:51:43:020PM1120816019Steve Wukitch019 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma
right gap is better
next: tweek RCUR smaller by 0.002
Load at 16-Aug-2012 13:46:55.00

Aug 16 2012 02:01:19:360PM1120816019Steve Wukitch020 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma

next: tweek RCUR smaller by 0.006 at 0.8
Load at 16-Aug-2012 14:00:53.00

Aug 16 2012 02:17:34:900PM1120816021Steve Wukitchfizzle

next: EF4 10A more positive (-1300 from -1310)

Aug 16 2012 02:28:11:013PM1120816022Steve Wukitch022 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma

next: repeat with different RF waveforms

Aug 16 2012 02:43:17:677PM1120816023Steve Wukitch023 demand: Ip wags around 0.8, nl04~1.5, BT~5.45
result: plasma - SL is happy

next: repeat with flat Ip at 0.93 MA
Load at 16-Aug-2012 14:39:54.00

Engineering Operator Comments
ShotTimeTypeStatusComment
109:03:08:327AMPlasmaOk
209:34:11:347AMPlasmaOk
309:46:44:777AMPlasmaOk
410:00:21:087AMPlasmaOk
510:15:42:937AMPlasmaOk
610:30:28:520AMPlasmaOk
710:46:37:557AMPlasmaOk
811:00:31:127AMPlasmaOk
911:20:18:020AMPlasmaOk
1011:40:38:530AMPlasmaOk
1111:53:35:817AMPlasmaOk
1212:08:19:313PMPlasmaOk
1312:20:41:900PMPlasmaOk
1412:34:17:413PMPlasmaOk
1512:48:49:457PMPlasmaOk
1601:01:15:393PMPlasmaOk
1701:13:43:540PMPlasmaOk
1801:26:25:040PMPlasmaOk
1901:39:10:410PMPlasmaOk
2001:52:48:207PMPlasmaOk
2102:06:27:993PMPlasmaOk
2202:19:27:717PMPlasmaOk
2302:33:30:617PMPlasmaOk
2402:48:10:537PMPlasmaOk

System Availability
Aug 16 2012 09:02:50:663AM
SystemAvailableCommentAvailability
Changed
OwnerDescriptionWho Can
Change
Active MHDnosecured - tagged outJun 2 2008 11:03:58:433AM (sears)Joe SnipesActive MHD Antennagolfit
BESyesBES system is onlineNov 22 2011 02:21:12:050PM (bespam)Bill RowanBeam Emission Spectroscopybespam,liao,rowan
BolometersyesMidplane diodes functioning properly. Midplane bolometers working and calibrated. DIV bolometers installed but not yet toaster calibratedApr 20 2012 09:57:29:520AM (mlreinke)Matt ReinkeBolometershutch,mlreinke
Boronizationyes Jun 15 2012 05:02:46:313PM (dekow)Jim IrbyBoronizationdekow,irby
CECEyesThe system is currently operational for Te tilde measurement. Talk to Choongki about the current configuration Jul 3 2012 04:38:00:317PM (nthoward)Anne WhiteCorrelation ECEnthoward,sck83,whitea
CNPAyesMultiple channel CNPA available, no safety risk for in-vessel accessApr 14 2011 12:01:59:693PM (parker)Ron ParkerCompact Neutral Analyzerparker
Cryopump - Upper Divertoryes Jun 15 2012 05:02:31:550PM (dekow)Brian LaBombardUpper Divertor Cryopumpdekow,irby,labombard
CXRSyescore-CXRS system is onlineNov 22 2011 02:21:22:280PM (bespam)Bill RowanCharge Exchange Spectroscopybespam,blip,liao,rachmcd,rowan
CXRS edgeyesMichael CHurchill has primary responsibility at the momentApr 19 2011 11:44:46:247AM (blip)Bruce LipshultzMeasurement of CXR light in the pedestal region at both the high- and low-field sidesblip,rmchurch
D Alphayes\ha2_bright is available; \SPECTROSCOPY::TOP.VUV.VIS_SIGNALS:MCP_VIS_SIG1 is not availableJul 1 2009 09:45:41:090AM (terry)Jim TerryBalmer Alpha Monitorirby,terry,wolfe
Dalsanosystem is is installed and aligned, but not functional (appears to be a broken cable)Dec 5 2011 02:41:42:867PM (marmar)Earl MarmarVisible Bremsstrahlung Imagingmarmar
Disruption Mitigationyestwo gas jet valves active as of Feb 2012May 15 2012 10:09:23:597AM (granetz)Robert GranetzGas Jetgranetz,whyte
Divertor IRno Mar 6 2007 10:50:41:677AM Glen WurdenDivertor IR Digital Videogwurden,terry
Divertor IR Spectroscopyno Mar 6 2007 10:51:39:897AM Glen WurdenDivertor IR Spectroscopygwurden,terry
DMBolo AXUV diodesyesDiodes are taking usable data. Not all post-processing code is working yet.Feb 1 2012 01:24:23:953PM (golynyk)Geoff OlynykSet of six AXUV diodes in a toroidal array of midplane wall boxes.golynyk,granetz,mlreinke,whyte
DNByes"The beam could break at any moment."May 15 2012 10:09:52:470AM (granetz)Robert GranetzDiagnostic Neutral Beamdterry,granetz,mochung
ECDCyes Apr 26 2012 03:23:19:057PM (dekow)Jim Irby2.45 GHz, 3 kW, discharge cleaning systemdekow,irby,pfeiffer
FRC-ECEyesFRC-ECE is onlineMay 14 2012 11:53:01:693AM (bespam)Perry PhillipsHeterodyne ECE-32 channelsbespam,liao,phillips,rowan,whitea
FTCIyesSystem OperationalMay 14 2012 11:50:45:590AM (irby)Jim IrbyFast two-color interferometerirby
G-Side RatiomaticyesInstalled April 25,2012. New controller installed 5/29/2012Jun 7 2012 10:40:00:957AM (toland)Brian LaBombardG-side ratiomatic ionization gaugelabombard,toland
Glow DischargenoHV cables disconnected and power supplies off. Electrical plugs have been disconnected, capped and red tagged.Mar 5 2012 10:21:53:460AM (dekow)Jim Irby1 kV, 5 A, glow discharge systemdekow,dterry,irby
GPCyesOperationalApr 27 2012 07:41:46:907AM (hubbard)Amanda HubbardECE Polychromaterhubbard
GPC2yesOperationalApr 27 2012 07:42:03:317AM (hubbard)Amanda HubbardECE Polychromaterhubbard
GPIyesThe Xpt-view, the midplane-view cameras are operational. The innerwall GPI (coupled to the fast-diodes) is available. Jul 1 2009 09:45:50:933AM (terry)Jim TerryGas Puff Imagingterry,zweben
H/Dyessystem is functional and taking dataDec 5 2011 02:42:29:857PM (marmar)Earl MarmarH/D Ratiomarmar
HEATyes Apr 26 2012 03:23:49:607PM (dekow)Gary Dekow - Machine Heaters -burke,dekow
Hirex JryesHirex-Jr has been installedJun 28 2010 03:36:33:420PM (rice)John RiceHigh Resolution X-Rayince,rice
Hirex SryesInstalled and aligned. Will be available for Ti/Vr profiles after focusing tests and locked modes are taken.Dec 6 2011 08:21:02:453AM (ypodpaly)John RiceHigh Resolution X-Raycgao,ldelgado,rice,ypodpaly
HXRyes32 Channels operational,, no safety risk for in-vessel accessApr 14 2011 12:05:24:810PM (parker)Ron ParkerHard X-Ray Arrayfaust,parker,schmidt
ICRF D-Antennayes May 31 2012 09:20:06:827AM (wukitch)Steve WukitchD-port antennawukitch,ylin
ICRF E-Antennayes May 31 2012 09:19:57:640AM (wukitch)Steve WukitchE-port antennawukitch,ylin
ICRF J-Antennayes May 31 2012 09:19:47:443AM (wukitch)Steve WukitchJ-port antennawukitch,ylin
Impurity SpectroscopyyesBeing upgraded with better optics and new spectrographs. Dan Miller has primary responsibility.Apr 19 2011 11:46:02:193AM (blip)Bruce LipshultzMeasurement of recycling light and impurity source rates at multiple surfaces around the tokamakblip,miller
Laser Blow-OffyesPumped Down, Laser has not yet been tested but otherwise operationalMay 14 2012 04:31:17:037PM (nthoward)Martin GreenwaldImpurity Injection Systemg,nthoward
Lower HybridyesLH is now available for plasma operation up to ~900 kW net power.Jul 3 2012 02:50:00:693PM (wallaceg)Ron ParkerLower Hybriddterry,parker,wallaceg
Lower Hybrid ReflectometernooffApr 15 2011 08:24:27:930AM (dominguez)Arturo DominguezLower Hybrid Reflectometerdominguez,marmar,parker,sgbaek
LoWEUSyesLoWEUS viewing the 10-30 nm region, spectral brightness vs. lambda and time are being stored in tree.Apr 20 2012 10:43:34:077AM (mlreinke)Matthew L. Reinke Long Wavelength Extreme Ultraviolet Spectrometermarkchil,mlreinke
LPInoBeam line removedMay 30 2008 02:09:12:833PM (bose)Earl MarmarLithium Pellet Injectorbose,marmar
Ly-alphanoMidplane Lyman-a not functioning. New B-PORT Lyman (BPLY) still being debugged.Jul 12 2012 08:52:28:233AM (mlreinke)Matt ReinkeLyman alpha camerasfaustian,labombard,mlreinke
Magneticsyes Dec 1 2011 11:51:51:970AM (g)Robert GranetzBp coils and flux loops for equilibrium controlgranetz,wolfe
McPhersonnoMcPherson under vacuum but is not run on a day-to-day basis. Can be requested if desired. LoWEUS has taken over as the primary Mo monitor.Jul 12 2012 08:53:14:937AM (mlreinke)Jim TerryVUV Spectrometermarkchil,mlreinke,terry
MichelsonyesVacuum 3-4e-8 T. Starting with Michelson at reduced speed.Apr 27 2012 07:42:41:960AM (hubbard)Amanda HubbardECE Te Profileshubbard,schmidt
MKSyes Dec 2 2011 12:27:47:163PM (toland)Brian LaBombardBaratron pressure gaugeslabombard,toland
MLPyesOperational. Connected to A-port probe systemMay 10 2012 08:40:19:910AM (labombard)Brian LaBombardMirror Langmuir Probe Electronics Systemlabombard
MSEyes2/29/2012 MSE operational. No HV or vacuum safety issuesFeb 29 2012 12:26:13:863PM (sscott)Steve ScottMotional Stark Effectjinseok,sscott
NeutronsyesVoltage is on for He3 detectors on J port. Remaining voltages will be turned on for the first run.Apr 23 2012 09:31:22:063AM (fiore)Catherine FioreNeutron Detectorsfiore
Neuts and HardsyesAll detectors Powered On --- Waiting for neutrons for calibrationNov 22 2011 01:05:24:380PM (irby)Jim IrbyX-Ray/Neutron Detectors at K-Horirby
NINJAyesC-bottom and new F-bottom system ready.Dec 2 2011 12:28:44:843PM (toland)Brian LaBombardNINJA gas pufflabombard,terry,toland
PCIyesOperational.Jul 10 2012 07:08:06:883PM (ntsujii)Miklos PorkolabPhase Contrast Imagingemd,ennever,ntsujii,porkolab
Penning GaugesyesHV power supplies turned ON in INIT, off in RECOOLMay 10 2012 08:41:03:000AM (labombard)Brian LaBombardPenning Ionization Gaugeslabombard
Plasma TVyesWIDE1, WIDE2 (chan 33), DANT, JANT and DIV are operational.Jul 1 2009 09:46:29:543AM (terry)Jim TerryVideo of plasma via several camerasdekow,irby,terry,wolfe
Polarimeteryes3 chords operational but with high noise levelJan 6 2012 04:22:20:903PM (irby)Jim IrbyC-Mod Polarimeterirby
Power - Alternator Air Switchyes Apr 26 2012 03:24:21:607PM (dekow)Gary DekowAlternator to Power Room Power Supply Connectioncochran,dekow,dterry,irby
Power - PEIyes Apr 26 2012 03:24:41:250PM (dekow)Gary DekowPEI Systemcochran,dekow,dterry,irby
Power - TMXyes Apr 26 2012 03:24:57:153PM (dekow)Gary DekowEf2s,. EFCs and A-Coilsbyford,cochran,dekow,dterry,irby
Power Systemsyes Apr 26 2012 03:25:14:497PM (dekow)Jim IrbyC-Mod Magnet Suppliesbyford,cochran,dekow,dterry,irby
Probe Array - ISDyesOperational. Some dead probes.May 10 2012 08:41:58:120AM (labombard)Brian LabombardInner Lower Divertor Probe Arraylabombard
Probe Array - LHyesOperational. 4 out of 6 probes working.May 10 2012 08:41:40:557AM (labombard)Brian LaBombardLower Hybrid Probe Arraylabombard
Probe Array - OSDyesOperational.May 10 2012 08:42:13:733AM (labombard)Brian LaBombardOuter Lower Divertor Probe Array (F and J)labombard
Probe Array - UDIVyesOperational. Some dead probes.May 10 2012 08:42:32:663AM (labombard)Brian LaBombardUpper Divertor Probe Arraylabombard
ReflectometeryesOn 1120608, the high frequency channels: 112, 140 and the variable, have been disconnected for some troubleshooting. All other channels are connectedJun 14 2012 11:28:59:603AM (dominguez)Earl MarmarReflectometerdominguez,marmar
Scanning Probe - ASPyesOperational. A variety of probe heads are ready for use.May 10 2012 08:43:10:937AM (labombard)Brian LaBombardA-Port Scanning Probelabombard
Scanning Probe - FSPyesOperational.May 10 2012 08:43:24:887AM (labombard)Brian LaBombardF-Port Scanning Probelabombard
Scanning Probe - WASPnoNot functioning. Probe tips are melted. Repair not performed during break.May 10 2012 08:44:43:137AM (labombard)Brian LaBombardInner Wall Scanning Probelabombard,nsmick
Shoelace AntennayesOperationalMay 10 2012 08:45:08:320AM (labombard)Brian LaBombardHigh-k active MHD antenna, for QCM, WCM studiesgolfit,labombard
SOL reflectometeryesc-port (top, middle, bottom) and h-port available. Only 1 of 4 locations can be used for each dischargeMay 1 2012 04:54:58:820PM (cornwall)Cornwall LauSOL reflectometercornwall,wukitch,ylin
SparkeryesSparker Power Supply powered up. Connected at K port using red cable 4/23/12 9:25AMApr 23 2012 12:06:10:983PM (parkin)Jim IrbyField Emission Preionization for C-Moddekow,irby,parkin
Surface Science StationyesSSS is under vacuum and fully available.Jul 3 2012 02:46:59:753PM (ochoukov)Bruce LipschultzRadially scanning probe located on K-portblip,ochoukov
TCIyesTCI lasers in operation May 14 2012 11:51:18:700AM (irby)Jim IrbyTwo-Color Interferometerirby,murray
TS - CoreyesOperating with both lasers, density calibration ongoing.Jul 19 2012 10:20:09:220AM (jrwalk)Jerry HughesCore Thomson scatteringjrwalk,jwhughes,yma
TS - EdgeyesOperating with both lasers, density calibration ongoing.Jul 19 2012 10:20:28:323AM (jrwalk)Jerry HughesMillimeter resolution edge Thomson scatteringjrwalk,jwhughes,yma
Vispecno350 and 670 nm, 4 spatial channelsNov 28 2007 09:58:35:493AM (agraf)Alex GrafVisible Spectrometeragraf
XEUSyesXEUS viewing the 1-6 nm region, spectral brightness vs. lambda and time are being stored in tree.Apr 20 2012 10:43:43:107AM (mlreinke)Matt ReinkeX-ray Extended Ultraviolet Spectrometermarkchil,mlreinke
XTOMOyesARRAY1->5 available. Specific channels on various arrays display issues.Apr 20 2012 05:36:28:523PM (faustian)Robert GranetzX-Ray Tomographyfaustian,granetz,mlreinke