Alcator C-Mod Run 1070724 Information

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Miniproposals
Miniproposal:511
Date Filed: 7/18/2007
Title:Study of ELM Structure, Dynamics and Energetics on Alcator C-Mod
First Author:Jim Terry
Session Leader:Jim Terry (shots 1-31)

Operators
Session leader(s):Jim Terry
Physics operator(s):Ian Hutchinson
Engineering operator(s):Bill Cochran,Sam Pierson,Ed Fitzgerald

Engineering Operator Run Comment
automatically entered by signon - please replace with real comment

Session Leader Plans
Entered: Jul 24 2007 10:41:18:320AM
Author: Jim Terry
This is another attempt at performing the work
started during run 1070719 - "Study of the Structure,
Dynamics, and Energetics of ELMs" - MP #511.
It is also a continuation of MPs #426 and #458.

It will utilize the following new capabilities
that should positively impact our investigation of ELMs:

Cyropumping,
A new array of probes mounted in the floor of the upper divertor,
A new view and fast camera for Gas-Puff-Imaging just
outboard of the typical location of the LSN X-pt.,
Additional fast magnetic sensors different toroidal locations,
An inward shift of the radial location of the
poloidal array of fast-diode views.

In order to utilize the cryopump and the upper
divertor probe array we will run
USN plasmas with REVERSED field and current.

In a well-boronized machine, we will begin
by trying to produce Type 1 ELMs in
in a less extreme version of the
non-standard JFT-2M shape in the USN
configuration. Instead of the JFT2M's upper
triangularity ~0.75, we will begin with
upper triangularity ~0.65. And instead of the JFT2M
shape's lower triangularity of ~0.15, we will start with a
somewhat higher value of ~0.25. Then, depending upon what is
allowed by the power supplies and depending on whether or not we
are producing ELMs, we will progress in steps closer toward
the JFT2M shape, observing any change in the ELM/pedestal behavior.

We will also attempt to produce Type I ELMs using
the reversed field, USN, cyropumped Ohmic H-modes
(e.g. 1070720022) as target plasmas for ICRF heating.
This target plasma exhibited Type III ELMs. We will turn on
the ICRF after the Ohmic H-mode is established.

If we produce ELMs using either of these two approaches, we will
increase the ICRF power from 2 MW to the highest available
power, in order to examine the ELM frequency vs RF power.

After producing discharges with ELMs, we will study the ELM
structure/dynamics
- by examining the X-pt-GPI images (150,000 frames/s with a
1 microsec integration time) and what is seen on the poloidal array of fast-diode views;
- by using the ASP in dwell mode (R=90.0, 91.0, and 92.0 cm mapped to midplane)
to examine the timing (1 Mhz digitization rate) of filaments reaching the probe relative
to those for the other fast ELM diagnostics;
- by using the antenna loading measurements (250 kHz) to examine the timing of filaments
reaching the antennas relative to those for the other fast diagnostics;
- by continuing investigation of hi-freq magnetic oscillation at filament ejection,

We will also study the ELM energetics
- by performing power scan, concentrating on ELMs at high power (>3MW if possible),
- by employing BES/DNB measurements for fast ne profiles during ELM crash,
- by employing upper fixed probes in ion-saturation mode to make ELM timing and energetics measurements,
- by examining the non-thermal electron generation at ELM crash using the ECE ,
- by examining soft x-ray signals at highest digitization frequency (100 kHz),
- by employing ASP in dwell mode in the far-SOL (~90 cm) to yield an
additional Te measurement in SOL (in addition to the ECE and TS measurements),
- and by making ELMs at two significantly different values for the outer gap.


Diagnostics: Core and edge TS*, TCI*,
ECE* (100kHz dig rate with outermost GPC
channel in the pedestal and outermost GPC2
channels outside the sepx),
midplane GPI*, X-pt GPI*,
Soft x-ray arrays (digitized at 100 kHz from 0.8 to 0.9 s)*,
fast magnetics (digitized at 10 MHz from 0.7 to 1.2 s)*,
ASP in dwell mode at R=90.0 cm, 91.0 cm, and
92.0 cm (mapped to midplane)*,
upper divertor probes (digitized at 1 MHz from 0.7 to 1.2 s)*,
IR camera*
BES (viewing the pedestal with a 1 MHz digitization rate)*
PCI (digitized at 10 MHz from 0.7 to 1.2 s),
reflectometry,
DALSA VB profiles

*ed diagnostics are crucial

Run Plan:

1.With well-boronized walls, start with 1070719006 with
reduced demands on the shape, i.e. dupper=0.65, dlower~0.25 -
observe discrete ELMs (3 good shots - with fast ELM diagnostics working).
2.Try to approach the JFT2M shape gradually as is allowed by
power supply capabilities - observe pedestal changes and
whether ELMs are produced.
(4 shots - with fast ELM diagnostics working).
3.If Type I ELMs are produced, repeat with increased ICRF
power - up to max available (2 good shots). If Type I ELMs
are not produced, then use shot 1070720022 (a cryopumped,
Ohmic H-mode plasma) as the target for ICRF heating (2MW)
and observe whether or not Type I ELMs are produced. If so,
then use this discharge for the following steps in the ELM study.
4.Repeat with cyropumping at optimum RF power level (2 good shots)
5.At optimum RF power and cyropumping (if that has improved the
reproducibility of the ELMs) change the target density to
NL_04=3e19 m-2 and NL_04=8e19 m-2 (2 shots per density - 4 shots total)
6.At optimum RF power, cyropumping, and target density, change
the outer gap to 3.0 cm and 1.0 cm. (2 shots per gap - 4 shots total)
7.Repeat at optimum RF power, cyropumping, and target density
with fast ELM diagnostics working (fast-magnetics, two GPI views,
upper divertor probes, ASP in dwell mode, BES/NBI, PCI,
X-ray arrays, antenna loading detection) (7 shots)
8.Repeat at optimum RF power, cyropumping, and target
density with 6 of the fast-diode views switched to
include the inboard radial array (2 shots)


Physics Operators Plans
Entered: Jul 23 2007 03:30:01:620PM
Author: Ian Hutchinson
MP#458 (also submitted MP, covering Idea #907) "ELM structure, dynamics, and
energetics"

Pre-Run Boronization request:
5-hr boronization with vertical field (Bv/Bt~0.1),
at higher-than-typical pressure - 55 mTorr foreline pressure,
with sweep from a min R_ec_resonance = 70 cm to a max
R_ec_resonance = 80 cm,
This minimum on the sweep is set by the desire to keep the upper divertor
probes clean.

This run will be reversed field, upper null, with cryopump.

Two hours ECDC in D2, finishing by 8AM. Pressure 2e-4 Torr,
sweep rmin/rdwell/rmax=44/45/103

acoils configured (-Dtop +Dbot +Jtop -Jbot) 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 (C-side) with 40 psi D2 Hybrid enabled (PG3)
fill NINJA to 10 psi D2 and ENABLE.

Enable the following gate valves and shutters, assuming no problems:
ECE, VUV, DNB, Z-bolo shutters

Torvac setup: Gate valves open after the shot

ICRF: Transmitters 1,2,3,4 in RUN-ON by 8:30
Start with 2MW (D+E) from 0.7 to 1.2sec as on 1060503022
We will probably want to add J later in the day.
LH: NO LH for this run

DNB: yes (with MSE polarizer removed, so that BES signal will be increased)

Cryopump: ready for operation after first successful plasma.

load shot 1070719006, but with reduced demands on triangularity,
i.e. dupper=0.65, dlower~0.25
Bt=+5.4 T
Ip=+0.9 MA
NL04=0.5e20 m-2
upper triangularity=0.65
lower triangularity=0.25
outer gap= 2.0 cm (this is different than 1060503022)
inner gap=2.0 cm
We'll be increasing the upper triangularity, decreasing the lower
triangularity, and varying outer gap and density, and using the cryopump.
At some point we will want to good to maximum available ICRF power.

If this approach does not produce good, Type I ELMs, we will load shot
1070720022 (a cryopumped, ELMing, Ohmic H-mode plasma) as the target for
ICRF heating (2MW) and observe whether or not Type I ELMs are produced.


Session Leader Summaries
Entered: Oct 16 2007 09:59:00:590AM
Author: Jim Terry
This was a successful run.

We succeeded in making the JFT2M shape
in USN with reversed fields and current.
We succeeded in making large discrete ELMs
in this shape. Eventually, however, we lost the
ELMs in the JFT2M shape presumably because the
boronization was waring off. (We observed that
the radiated power increased much faster for the
non-ELMing shots (which were also shots later in the day)
than it had for the ELMing H-mode shots earlier
in the day.)

We produced ELMS at outer gaps ranging from 2.2 cm (1070724013)
to 1.2 cm (1070724011).

We observed ELMs first the 1st time with the
following diagnotics:
upper divertor probes - use /home/labombard/scopes/fmp_fast_digitizer_data.dat
ASP in dwell mode - use /home/labombard/scopes/asp_processed_vs_time.dat
soft x-ray edge array - use /home/granetz/scopes/xtomo_array_4.dat
(Chord 01 is innermost. The 38 chords cover about 38 mm in the pedestal region. Filter is 10 micrometers of beryllium.)
Use also /home/granetz/scopes/xtomo_array_3.dat to look at the core and edge channels, sinec many ELMs are triggered by sawtooth crashes.

BES (with beam both on and off) - use /home/terry/scopes/bes_scope.dat
reflectometer - use Arturo's widget-based avalysis /home/dominguez/reflectometry/mywidget/plotwidget.pro

We also observed ELMs with diagnostics that have been used
previously for this purpose:
GPI fast-diode arrays
fast-magnetics
PCI
ECE

We were unsuccessful in producing ELMs using the cyropumped
Ohmic H-mode target plasmas. See shot 024.

We were successful in making an H-mode in the JFT2M shape in the
UNFAVORABLE gradB drift direction and we observed ELMs in this
case. Pedestal Te was lower in this scenario (500 eV as opposed
to 800-1000eV)

Following is a list of the useful shots:
Shot ELMs cryo outer gap tri_upper tri_lower target ne
(times)
004 yes (7) no 1.5 0.73 0.12 4.7(19)
006 yes (6) no 1.8 0.73 0.16 5.0(19)
(0.799,0.832,0.853,0.874,0.892,0.919)
007 yes (2) no 1.5 0.65 0.16 5.1(19)
(0.785,0.846)
008 yes (2) no 1.4 0.65 0.14 4.9(19)
(0.824,0.840)
009 yes (7) yes 1.4 0.65 0.17 4.8(19)
010 yes yes 1.4 0.65 0.17 4.1(19)
(0.785,0.811, some late)
011 yes (5) yes 1.2 0.65 0.17 6.0(19)
(small ELMs between 0.7712 and 0.7782, larger ELMs at 0.77869,0.7816,0.79165,0.82137,0.8496 (small), and 0.85023)
012 yes (3) yes 1.5 0.66 0.17 5.9(19)
(0.774,0.794,0.820)
013 yes (6) yes 2.2 0.66 0.16 5.3(19)
(small- between 0.78-0.81)
014 yes (4) yes 2.0 0.65 0.15 5.1(19)
(small ELMs at 0.7877, 0.7902, and 0.7938, and 0.80866, larger ELMs at 0.9397,0.9678)
015 yes (1) yes 2.0 0.63 0.16 5.0(19)
(0.766)

024 no yes ICRF heated Ohmic H-mode target
027 no, but QCM no NOTE: outer gap scanned during EDA from 1.0 to 3.0
028 no, but QCM no NOTE: outer gap scanned during EDA from 0.5 to 3.0
029 yes no 2.2 0.16 0.77 6.0(19)
(small between 0.81 and 0.87) NOTE: UNFAVORABLE DRIFT DIRECTION

The X-pt view camera didn't see much emission; I will have to investigate
whether or not I saw anything. Also for many of the shots the camera data did NOT
get transferred from the PC to the tree.

Physics Operator Summaries
Entered: Jul 24 2007 05:16:42:083PM
Author: Ian Hutchinson
Summary

Succeeded in getting some upper null JFT2-M shapes that did not
disrupt. This required backing off on the requested Rxu (making it
more positive), to prevent the EF2U from railing at zero. Then a
reasonable number of shots were obtained which showed a few elms.

None of the attempts to adjust the control system to tolerate the
railing of the EF2s was successful. It was observed that the slow
oscillations that are triggered are not purely vertical motion. A
theory that perhaps the railing of the power supply caused a major
coupling to other controllers was put forward. One way to test that
and try to prevent it is to zero the EF2 coefficients in the vertical
controller. This was carried out (see shot 19) and made no
difference. The instability was still present. Of course it is just a
guess that the vertical controller was the problem. EF2 is involved in
all the controllers, so clearly the railing of one of the EF2s couples
all the controllers together in a different way from when it is
not. Therefore it is difficult to disentangle which is the major
source of the instability. Full scale simulations are probably
necessary.


Scorecard

  Shot,Duration(s),Ipmax(MA),Result  Shot,Duration(s),Ipmax,Result
  |    1   No Ip                   |    2   No Ip                   |
  |   03   0.000   0.032   Dud     |   04   1.482   0.924   Plasma  |
  |   05   0.000   0.044   Dud     |   06   1.286   0.927   Plasma  |
  |   07   1.944   0.923   Plasma  |   08   1.943   0.924   Plasma  |
  |   09   1.946   0.928   Plasma  |   10   1.943   0.927   Plasma  |
  |   11   1.720   0.930   Plasma  |   12   1.943   0.926   Plasma  |
  |   13   1.944   0.924   Plasma  |   14   1.945   0.922   Plasma  |
  |   15   1.946   0.928   Plasma  |   16   1.945   0.930   Plasma  |
  |   17   1.943   0.924   Plasma  |   18   1.942   0.925   Plasma  |
  |   19   1.136   0.915   Plasma  |   20   0.000   0.049   Dud     |
  |   21   1.958   0.813   Plasma  |   22   1.960   0.809   Plasma  |
  |   23   1.958   0.811   Plasma  |   24   1.959   0.818   Plasma  |
  |   25   1.959   0.822   Plasma  |   26   0.000   0.002   Dud     |
  |   27   1.960   0.826   Plasma  |   28   1.959   0.824   Plasma  |
  |   29   1.929   0.920   Plasma  |   30   0.000   0.048   Fizzle  |
  |   31   0.363   0.818   Plasma 
Date 1070724:  31 shots.  24 plasmas.   1 fizzles.   4 duds.   2 System Error.
        (Plasma = Ip gt 60.0 kA   Dud = H_alpha lt  0.40 V)
Total plasma duration: 43.01 s (exceeding  100 kA)


Session Leader Comments
Jul 24 2007 10:41:58:173AMJim TerrySetups for the fast ELM diagnotics:
upper divertor probes (in I_sat mode digitized at 1 MHz from 0.7 to 1.2 s),
later in the run use ASP in dwell mode at R=92.0 cm
mapped to midplane), initially in sweep mode to get Te,
then in I_sat mode
Soft x-ray arrays (digitized at 100 kHz for as long as possible
starting at 0.8 s),
fast magnetics (digitized at 10 MHz from 0.7 to 1.2 s),
PCI (digitized at 10 MHz from 0.7 to 1.2 s),
ECE with 100 kHz sample rate
reflectometry (1 MHz sample rate, with freqs 50, 60, 75, 88, 110

X-pt view camera: 90909 frames/s with 9 microsec integration time
fast-diodes: data window was from 0.700 to 1.224 sec
diode # trans fiber # view F/no
1 GPI #3 OUTER SOL 36 F/1.4
2 GPI #2 OUTER SOL 22 F/1.4
3 GPI #1 OUTER SOL 5 F/1.4
4 GPI #4 OUTER SOL 23 F/4.0
5 GPI #5 OUTER SOL 10 F/4.0
6 #39 OUTER SOL 9 F/4.0
7 #40 OUTER SOL 7 F/1.4
8 #41 OUTER SOL 11 F/5.6
9 #42 OUTER SOL 12 F/4.0
10 #43 OUTER SOL 13 F/5.6
11 #44 OUTER SOL 14 F/4.0
12 #45 OUTER SOL 6 F/1.4
13 #46 OUTER SOL 29 F/5.6
14 #47 OUTER SOL 31 F/1.4
15 #48 OUTER SOL 32 F/1.4
16 #49 OUTER SOL 33 F/2.8
17 #50 OUTER SOL 34 F/4.0
18 #51 OUTER SOL 35 F/4.0
19 #52 OUTER SOL 3 F/1.4
20 #20 OUTER SOL 37 F/4.0
21 #21 OUTER SOL 38 F/2.8
22 #22 OUTER SOL 39 F/2.8
23 #26 OUTER SOL 40 F/2.0


NINJA puffing D2 from capillaries K-bolo and A-B lim
initially with trig at 0.7 s for 0.1 s
plenum pressure is 472 mTorr

Aug 1 2007 04:13:53:603PMJim TerryThe NINJA history for this run was as follows:
shot capillary trig time duration torr-l torr-l
(gauge 1) (gauge 2)
1070724002, AB Lim, 0.700, 0.100, 7.489, 7.794, 0.000
1070724002, K Bolo, 0.700, 0.100
1070724003, AB Lim, 0.700, 0.100, 7.657, 7.976, 0.000
1070724003, K Bolo, 0.700, 0.100
1070724004, AB Lim, 0.700, 0.100, 7.571, 7.902, 0.000
1070724004, K Bolo, 0.700, 0.100
1070724005, AB Lim, 0.650, 0.100, 7.494, 7.814, 0.000
1070724005, K Bolo, 0.650, 0.100
1070724006, AB Lim, 0.650, 0.100, 7.457, 7.792, 0.000
1070724006, K Bolo, 0.650, 0.100
1070724007, AB Lim, 0.650, 0.100, 7.368, 7.673, 0.000
1070724007, K Bolo, 0.650, 0.100
1070724008, AB Lim, 0.650, 0.100, 7.327, 7.672, 0.000
1070724008, K Bolo, 0.650, 0.100
1070724009, AB Lim, 0.650, 0.100, 7.256, 7.520, 0.000
1070724009, K Bolo, 0.650, 0.100
1070724010, AB Lim, 0.650, 0.100, 7.181, 7.456, 0.000
1070724010, K Bolo, 0.650, 0.100
1070724011, AB Lim, 0.650, 0.100, 7.121, 7.412, 0.000
1070724011, K Bolo, 0.650, 0.100
1070724012, AB Lim, 0.650, 0.100, 7.057, 7.384, 0.000
1070724012, K Bolo, 0.650, 0.100
1070724013, AB Lim, 0.650, 0.100, 7.012, 7.285, 0.000
1070724013, K Bolo, 0.650, 0.100
1070724014, AB Lim, 0.650, 0.100, 6.948, 7.141, 0.000
1070724014, K Bolo, 0.650, 0.100
1070724015, AB Lim, 0.650, 0.100, 6.866, 7.077, 0.000
1070724015, K Bolo, 0.650, 0.100
1070724016, AB Lim, 0.620, 0.100, 6.786, 7.165, 0.000
1070724016, K Bolo, 0.620, 0.100
1070724017, AB Lim, 0.620, 0.100, 6.762, 7.138, 0.000
1070724017, K Bolo, 0.620, 0.100
1070724018, AB Lim, 0.620, 0.100, 6.705, 6.888, 0.000
1070724018, K Bolo, 0.620, 0.100
1070724019, AB Lim, 0.620, 0.100, 6.646, 6.940, 0.000
1070724019, K Bolo, 0.620, 0.100
1070724020, AB Lim, 0.620, 0.100, 6.570, 6.880, 0.000
1070724020, K Bolo, 0.620, 0.100
1070724021, AB Lim, 0.620, 0.100, 7.885, 8.240, 0.000
1070724021, K Bolo, 0.620, 0.100
1070724022, AB Lim, 0.620, 0.100, 7.861, 8.194, 0.000
1070724022, K Bolo, 0.620, 0.100
1070724023, AB Lim, 0.620, 0.100, 7.851, 8.148, 0.000
1070724023, K Bolo, 0.620, 0.100
1070724024, AB Lim, 0.620, 0.100, 7.822, 8.167, 0.000
1070724024, K Bolo, 0.620, 0.100
1070724025, AB Lim, 0.620, 0.100, 7.784, 8.142, 0.000
1070724025, K Bolo, 0.620, 0.100
1070724027, AB Lim, 0.620, 0.140, 8.616, 8.926, 0.000
1070724027, K Bolo, 0.620, 0.140
1070724028, AB Lim, 0.620, 0.140, 8.581, 8.832, 0.000
1070724028, K Bolo, 0.620, 0.140
1070724029, AB Lim, 0.620, 0.140, 8.580, 8.773, 0.000
1070724029, K Bolo, 0.620, 0.140
1070724030, AB Lim, 0.620, 0.140, 8.537, 8.780, 0.000
1070724030, K Bolo, 0.620, 0.140
1070724031, AB Lim, 0.620, 0.140, 8.515, 8.788, 0.000
1070724031, K Bolo, 0.620, 0.140

Jul 24 2007 11:30:38:140AM1070724004Jim TerryGood shot
H-mode with some isolated ELMs disrupted
at 1.485 s

NINJA puffing D2 from capillaries K-bolo and A-B lim
initially with trig at 0.7 s for 0.1 s
plenum pressure is 472 mTorr


Diodes are good, but diode 11 is slughtly saturated.

The B-side camera was setup with both lenses at
infinity and both apertures open. The view is badly
out of focus and saturated (gain=700, shutter=60).

nothing obvious on the X-pt camera
IR camera didn't take data.
Aug 1 2007 10:08:52:480AM1070724006Jim TerryCryopump OFF for this shot

Good shot
NL04 of target=5.0e19
outer gap=1.8 cm
upper tri=0.73, lower tri=0.16
H-mode with 6 isolated ELMs (0.799,0.832,0.853,0.874,0.892,0.919 s)
Best ELMs yet for this run.

Good edge soft x-ray data

NINJA puffing D2 from capillaries K-bolo and A-B lim
initially with trig at 0.6 s for 0.1 s
plenum pressure is 472 mTorr


Jul 24 2007 11:45:40:470AM1070724008Jim TerryGood shot
H-mode with 2 isolated ELMs, goes into EDA
NL04 is 1.45e20 at 1.2 s

NINJA puffing D2 from capillaries K-bolo and A-B lim
initially with trig at 0.7 s for 0.1 s
plenum pressure is 472 mTorr


Jul 24 2007 11:38:09:833AM1070724009Jim TerryCryopump on this shot - hope is that it will
reduce the density rise.

Good shot
H-mode with 6 isolated ELMs, goes into EDA
pump dropped the H-mode density slightly
1.486e20 at 1.2 s
NINJA puffing D2 from capillaries K-bolo and A-B lim
initially with trig at 0.7 s for 0.1 s
plenum pressure is 472 mTorr


Jul 24 2007 03:46:19:167PM1070724020Jim TerryFor this shot load shot 1070720022 to try and reproduce
the Ohmic H-mode with Type III ELMs. We do this because the radiated
power rise is much greater (even for the 2MW of ICRF power) than
it was for the earlier ELMing shots. For example for shot 019
the rate of rise in P_rad is at least twice that for shot 004.
We have also regained the highly shaped plasmas
(upper tri>0.7, lower tri=0.15)
Cryopump ON
Request no RF.

Thus we are not doing the highly-shaped (JFT2M) plasmas
any more.

Fizzle

All diagnostic timings are the same.
Jul 24 2007 03:45:44:340PM1070724021Jim TerryCryopump ON
Another attempt for an Ohmic H-mode target.
No RF
Argon ON at 100 ms puff

Successful plasma - short Ohmic H-mode 0.55 to 0.63 s

All diagnostic timings are the same.
Jul 24 2007 03:45:08:057PM1070724022Jim TerryCryopumping ON
Argon ON
Another attempt for an Ohmic H-mode target.
No RF

Successful plasma - but no H-mode

All diagnostic timings are the same.
Jul 24 2007 03:44:09:477PM1070724023Jim TerryCryopumping ON
Another attempt for an Ohmic H-mode target.
No RF
Argon ON at 100 ms puff

Successful plasma - Ohmic H-mode from 0.53 to 0.75 s
Small ELMs (not Type I)

All diagnostic timings are the same.
Jul 24 2007 03:44:38:477PM1070724024Jim TerryCryopumping ON
No Argon puff
Another attempt for an Ohmic H-mode target.
Turn on RF at 0.67 s when the plasma may be in H-mode.

Successful plasma - Ohmic H-mode starting at 0.53 with
small ELMs (not Type I)- RF injects (1.2 MW) into H-mode,
but no ELMs after RF turns on.

All diagnostic timings are the same.
Jul 24 2007 04:03:32:500PM1070724025Jim TerryNo Cryopumping because the cyro system is out of LHe
No Argon puff
Another attempt for an Ohmic H-mode target.
Turn on RF at 0.67 s when the plasma may be in H-mode.

Successful plasma - No Ohmic H-mode
RF injects (1.85 MW) and makes a long steady EDA,
but no ELMs after RF turns on.

All diagnostic timings are the same.
Jul 24 2007 04:37:00:180PM1070724027Jim TerryNo Cryopumping
No Argon puff
Another attempt for an Ohmic H-mode target.
Turn on RF at 0.67 s when the plasma may be in H-mode.
Attemp to scan the outer gap from 1.0 cm at 0.76 sec to 3.0 cm
at 1.06 s, const after that.

Successful plasma - No Ohmic H-mode
RF injects (1.85 MW) and makes a long steady EDA,
but no ELMs after RF turns on.

NINJA puffing D2 from capillaries K-bolo and A-B lim
with trig at 0.62 s for 0.14 s (longer duration)
plenum pressure is 472 mTorr

All other diagnostic timings are the same.

Jul 24 2007 04:38:30:180PM1070724028Jim TerryNo Cryopumping
No Argon puff
Another attempt for an Ohmic H-mode target.
Turn on RF at 0.67 s when the plasma may be in H-mode.
Attemp to scan the outer gap from 0.5 cm at 0.5 sec to 3.0 cm
at 1.06 s, const after that.

Successful plasma - No Ohmic H-mode
RF injects (2 MW) and makes a long steady EDA,
but no ELMs after RF turns on. Good outer gap scan.

NINJA puffing D2 from capillaries K-bolo and A-B lim
with trig at 0.62 s for 0.14 s (longer duration)
plenum pressure is 472 mTorr

All other diagnostic timings are the same.

Jul 24 2007 04:58:36:610PM1070724029Jim TerryNo Cryopumping
No Argon puff
Now try for LSN JFT2M-shaped plasma.
Highest available ICRF power

Successful plasma -
RF injects up to 3 MW with many trips
and makes some transient H-modes, with
some small ELMs, but with clear precursors

NINJA puffing D2 from capillaries K-bolo and A-B lim
with trig at 0.62 s for 0.14 s (longer duration)
plenum pressure is 472 mTorr

All other diagnostic timings are the same.

Jul 24 2007 04:59:07:860PM1070724030Jim TerryNo Cryopumping
No Argon puff
Repeat try for LSN JFT2M-shaped plasma.
Highest available ICRF power

fizzle
Jul 24 2007 05:18:04:880PM1070724031Jim TerryNo Cryopumping
No Argon puff
Repeat try for LSN JFT2M-shaped plasma.
Highest available ICRF power

disrupted at 0.36 s for no obvious reason

Physics Operator Comments
Jul 24 2007 09:19:36:060AMIan HutchinsonLoad from 1070719006

Reduce ramp rate of zxl during the .3s+ period by moving the -.08 point to time
0.7s: a ~60% reduction in slew.

Raise rxl by about 1cm to try to reduce the negative demand on EF2L.

Load.
Jul 24 2007 09:53:11:363AM1070724001Ian HutchinsonSystem failure
Jul 24 2007 09:53:20:897AM1070724002Ian HutchinsonSystem Failure
Jul 24 2007 10:17:57:080AM1070724003Ian HutchinsonEF3 failure.
Jul 24 2007 10:33:54:090AM1070724004Ian HutchinsonPlasma disrupts at rampdown. Still railing the EF2 upper.
Late breakdown.

Lower EF4 to +1330A from +1335A.
Increase slow Zcur Derivative to 1.5 from .7 to try to stabilize.

zxl to -.05 from -.08 to try to avoid ef2u saturations.
Jul 24 2007 11:00:25:167AM1070724005Ian HutchinsonDud. Cryopump ran amok and lowered fill to .02mtorr.
Jul 24 2007 01:22:21:610PM1070724006Ian HutchinsonPlasma. If anything more unstable.

Rxu to -.03 from -.055. Proportional to 3 from 4.
Jul 24 2007 11:26:39:070AM1070724007Ian HutchinsonPlasma. EF2U comes out of saturation and we lose the vertical instability.
Triangularity about 0.6 upper.

EF4 to -1300A from -2000A in segment 2 to try to adjust the EF2 balance.
Jul 24 2007 11:36:29:973AM1070724008Ian HutchinsonPlasma. Slightly more oscillation on coil currents, but still not saturated.
Triangularity about .63 upper.

Cryopump turning on. Raise fill puff to 32 ms.
Small tweak of EF4 when it is supposed to cross over, to moderate lurch.
Jul 24 2007 11:46:02:047AM1070724009Ian HutchinsonPlasma. Somewhat lower density rise rate and more elms.

Lower nl04 demand to .4 from .5
Decrease EF4 gain in an additional step at .2s.
Allow EF4 to be higher before .5s.
Jul 24 2007 11:59:48:280AM1070724010Ian HutchinsonPlasma. Pellet injected in ramp down.
Got earlier EF4 crossover but still there seem to be a lot of wiggles on
the EF2/EF4 system.

Add Derivative of .5 to ef2byef4
nl04 to .6
Jul 24 2007 12:14:52:877PM1070724011Ian HutchinsonPlasma. Disrupts at pellet injection.

Further EF4 tweaks. Derivative to 1.
Jul 24 2007 12:31:56:927PM1070724012Ian HutchinsonPlasma.

Ef2byef4 proportional to 1.5 from 2.
Tweak ef4 value.
Jul 24 2007 12:49:36:200PM1070724013Ian HutchinsonPlasma.

Set ef2byef4 to a rational value: 2500 instead of 4000.
Then set EF4 to be what we really want it to be so the two controllers are
not fighting each other.
Jul 24 2007 01:01:00:557PM1070724014Ian HutchinsonPlasma.
Adjustments of the ef2/ef4 system successful. We are now not fighting so much.

Lower slow zcur derivative back down to 1.
Jul 24 2007 01:23:14:440PM1070724015Ian HutchinsonPlasma.

Slow zcur. Enter a new controller at time 0.5. XCONTIHH. Call it. Inspect it.
For some reason there are differences with the old one. There should not be
The differences are small. Ignore them for now.
Edit the controller. Zero the EF2 gains in this controller.

Zxl to +0.005.
Jul 24 2007 01:32:47:920PM1070724016Ian HutchinsonPlasma. New controller runs ok. Plasma did not change much.

Rxu to -.04 from -.03 to increase the upper triangularity.
Lower EF4 early to try to keep it from zeroing prior to .5s
Jul 24 2007 01:47:49:470PM1070724017Ian HutchinsonPlasma. Got upper triangularity in the 0.65 ballpark. EF2s did not quite saturate.

Rxu to -.05.
Jul 24 2007 02:03:42:470PM1070724018Ian HutchinsonPlasma. EF2U bounces into and out of the rail but not a problem.

Increase Rcur by 0.005 to drop right gap to 2cm.
Jul 24 2007 02:27:00:637PM1070724019Ian HutchinsonPlasma disrupts at 1.12s because of slowly growing oscillation.
This shows that simply removing the EF2 from the slow zcur controller does not
fix the slow vertical instability when EF2U rails.

Looking at the equilibrium, it looks as if the oscillation in predominantly
in the upper x-point position, which goes in a somewhat circular motion.
The vertical position is, of course, also affected.

Move second slow-zcur controller switch out of the way to 2.5s.

Load from 1070720022. Load.
Jul 24 2007 02:42:59:940PM1070724020Ian HutchinsonFizzle.

Import segment 1 from shot 19. Load.
Jul 24 2007 03:09:36:140PM1070724021Ian HutchinsonPlasma.

Argon puff to 10ms from 100ms. (I.e. pretty much off.)
Jul 24 2007 03:26:11:830PM1070724022Ian HutchinsonPlasma. Still no real H-mode.

Raise current to 1 MA.
Jul 24 2007 03:44:38:557PM1070724023Ian HutchinsonPlasma. But only .8MA. I now realize that I ought to have been changing segment 3 not segment 2.

Set Argon REALLY off. But leave at 0.8MA.
Jul 24 2007 03:58:28:713PM1070724024Ian HutchinsonPlasma.

Set fill puff to 21ms because of cryopump out of helium.
Jul 24 2007 04:20:35:457PM1070724025Ian HutchinsonPlasma.

Set gap scan to increase the gap by 2cm from .76s to 1.06s.
Jul 24 2007 04:20:51:190PM1070724026Ian HutchinsonNo power shot because I made a mistake.
Jul 24 2007 04:35:59:130PM1070724027Ian HutchinsonPlasma. Got the gap scan we wanted.

Start the scan further in and earlier.
Jul 24 2007 04:45:51:970PM1070724028Ian HutchinsonPlasma.

Load segment 2 from 1060503022. Do the calls and flips for abnormal field
and broken loops. Set Ar to negligible pulse.
Jul 24 2007 04:52:07:227PM1070724029Ian HutchinsonPlasma. Some EF2L railing.

Tweak the ef2/ef4 system feedback in the same way as we did for the upper null
shot to get sensible balancing and control instead of fighting two incorrect
settings.

Jul 24 2007 05:04:21:587PM1070724030Ian HutchinsonFizzle.

Br offset to .0025 from .002.
Jul 24 2007 05:05:30:650PM1070724031Ian HutchinsonPlasma disrupts at 0.36. Looks like a brick.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:18:43:140AMPlasmaBadnetwork failure
209:39:28:460AMPlasmaBadnetwork problem
309:51:18:470AMPlasmaBadEF3 Aux PS opened before shot
410:07:55:053AMPlasmaOk
510:31:16:090AMPlasmaOk
610:47:47:493AMPlasmaOk
711:02:56:857AMPlasmaOk
811:17:30:657AMPlasmaOk
911:30:13:747AMPlasmaOk
1011:44:01:217AMPlasmaOk
1111:57:51:733AMPlasmaOk
1212:13:17:297PMPlasmaOk
1312:27:49:500PMPlasmaOk
1412:40:52:487PMPlasmaOk
1512:57:26:707PMPlasmaOk
1601:16:16:760PMPlasmaOk
1701:28:53:463PMPlasmaOk
1801:42:31:570PMPlasmaOk
1902:01:47:453PMPlasmaOk
2002:24:44:027PMPlasmaOk
2102:41:23:077PMPlasmaOk
2202:54:30:483PMPlasmaOk
2303:12:57:177PMPlasmaOk
2403:28:41:053PMPlasmaOk
2503:45:46:620PMPlasmaOk
2603:59:16:417PMTestOkThis was a requested no power shot
2704:11:58:027PMPlasmaOk
2804:24:40:103PMPlasmaOk
2904:37:11:727PMPlasmaOk
3004:49:57:630PMPlasmaOk
3105:02:29:350PMPlasmaOk

System Availability
Jul 24 2007 09:18:19:997AM
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 and operational, data in the tree. Outboard midplane AXUV calibrated and operational, data in the tree. Full midplane and divertor views being digitized.Jul 19 2007 04:48PM (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.Jun 20 2007 05:35PM (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-ECEnoOnly high frequency channels now working (17 to 32). Ch 22 has bad video amp. LO is OK. Problem looks to be in mixer amp unit.Jul 11 2007 10:52AM (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 1,5,8,10,17) operational. Jun 08 2007 08:29AM (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. Max power is about 1.5 MWJun 20 2007 09:23AM (ylin)Steve WukitchD-port antennawukitch,ylin
ICRF E-Antennayes80 MHz. Maxc power is about 1.5 MWJun 20 2007 09:23AM (ylin)Steve WukitchE-port antennawukitch,ylin
ICRF J-Antennayes78 MHz. 4-strap configuration. Max ~ 3 MW.Jul 17 2007 03:52PM (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 calibrated and operational, data being stored in tree. Divertor views showing significant noise, and not available. Upper view being digitized and analyzed.Jul 19 2007 04:49PM (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
Reflectometeryes50, 60, 75 88, 88l,88u, 110 and the variable frequency channel are operational. Still in testing. Variable frequency channel set at 8V (136GHz)Jul 24 2007 08:08AM (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, 10 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.Jul 11 2007 09:18AM (jwhughes)Jerry HughesCore Thomson scatteringjwhughes
TS - Edgeyes2 lasers, 20 spatial channels. Fiber holder position is -103.0mm. Density is calibrated according to Raman scattering results from 26 May, supplemented with ECE cutoffs obtained on shot 1070531015.Jul 19 2007 06:10PM (jwhughes)Jerry HughesMillimeter resolution edge Thomson scatteringjwhughes
Vispecyes350 and 670 nm, 4 spatial channelsMay 04 2007 01:02PM (agraf)Alex GrafVisible Spectrometeragraf