Alcator C-Mod Run 1050413 Information

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Miniproposals
Miniproposal:333
Date Filed: 4/10/2003
Title:Density Limits and Turbulence
First Author:Martin Greenwald
Session Leader:Martin Greenwald (shots 18-31)
Miniproposal:348a
Date Filed: 6/27/2003
Title:Initial Tests of the Boron Injector
First Author:Jim Irby
Session Leader:Jim Irby (shots 1-17)

Operators
Session leader(s):Jim Irby,Martin Greenwald
Physics operator(s):Robert Granetz
Engineering operator(s):Sam Pierson

Engineering Operator Run Comment
MP #402 EO Pierson SL Wolfe PO Irby

Session Leader Plans
Entered: Apr 12 2005 11:57:06:157AM
Author: Steve Wolfe
Run Plan for Backup Experiment of 1050413 part 2.
MP#402 "Locked mode studies at different toroidal phase"
SL: wolfe

This experiment will be run on 1050413 only if MP#333 is determined not to be
possible. The plan for the other day scheduled for this MP, 1050415, will be
substantially different because it will start with the Acoil configuration
used in Hender's MP#398 that morning. 

The purpose of these experiments is to improve our characterization of the
C-Mod intrinsic error fields, and to investigate the dependence of the 2/1
locked mode threshold on the m=1 and m=3 sidebands. 

A-coils should be configured [+Btop -Bbot -Gtop +Gbot] (rotated quadrupole,
phi=-49 deg.). Since neither of the other experiments planned for the day
should require A-coil for locked mode suppression, it would be best to set
this configuration before the run. In this case, the A-coils should be
DISABLED for the other experiments. Note that the A-coils should be put back
in the standard configuration [+Dtop -Dbot -Jtop +Jbot] for Thursday's run.

Note: Nominal intrinsic error field has phi~ -160 degrees.

We will try to maximize the data in each coil configuration before moving on
to the next. This plan therefore includes elements of both Day 1 and Day 2
from the MP.

1. Establish shot with 1MA, 5.4T, NL04=1.1e20, Acoil off (e.g. 1050412008, 
   tweak nl04 program).
   Verify that no intrinsic locked mode appears. If it does, raise
   NL04. [1-2shots] 
2. A) Program Acoil current to maximum (program 4000A, expect 3600A).[1 shot]
   B) If locked mode appears then reduce Acoil program to bracket the
   threshold. Otherwise, Reduce NL04 by 10% and try again. [1-3 shots]
   C) Program decreasing density (NL04 1.5->0.5e20) and Acoil current=1660A
   (program ~2100A) (B21_app~4.4G), and determine locking density. [1 shot]
3. Reverse Acoil power supply leads [-Btop +Bbot +Gtop -Gbot] (rotated
   quadrupole, phi=131 degrees). 
   A) Program 4000A in Acoil [1 shot]
   B) If locked mode appears, bracket the threshold. Otherwise, proceed to
   step C. [0-3 shots]
   C) Repeat 2C in this orientation, Acoil current=1660A again. [1 shot]
4. Change Acoil taps to [-Btop -Bbot +Gtop +Gbot] (rotated dipole, phi=-142
   degrees)
   A) Program Acoil for 4000A [1 shot]
   B) If locked mode appears, reduce Acoil current to bracket the
   threshold. [0-3 shots]
   C) Repeat 2C, but with Acoil current at maximum (4000A). [1 shot]
5. Reverse Acoil power supply leads [+Btop +Bbot -Gtop -Gbot] (rotated dipole,
   +38 degrees). This should be in the suppressing direction, and I don't
   really expect to be able to excite a locked mode, but for completeness:
   A) Program Acoil for 4000A [1 shot]
   B) If locked mode appears (unlikely) bracket the threshold [0-3shots]
   C) Run decreasing density shot with Acoil program at maximum (4000A
   program) and determine locking density. [1 shot]

I don't expect to get past this point in a half-day, with tap
changes. Actually, it would be doing well to get through step 3. If by some
miracle we get this far, then the next case would be the standard dipole
[+Dtop +Dbot -Jtop -Jbot] phi=113 degrees. The acoil current for step C would
be 2560A (program about 3000). 



Entered: Apr 12 2005 02:57:34:577PM
Author: Martin Greenwald
mp 333
The goal is to obtain the evolution of the edge temperature profile as the density limit is approached. We will run at higher q than are earlier density limit runs so that the ECE is not cut off. The basic conditions are:

6 T, 0.5 MA
raise density (slowly) to limit which should be at nebar = 3.2e20
shot 1021107012 is a sample for shape and density rise

We should be ready to use inner wall puffing with the ninja system - previous density limit experiments required this.

The ECE should be set up to get best spatial coverage from gpc and gpc2 in the edge region (1-3 cm inside lcfs).

We want edge and core TS working

We want GPI and Halpha fluctuation arrays if available

(If we are wildly successful, we would repeat at 0.3 MA)
Entered: Apr 12 2005 10:13:53:577PM
Author: Jim Irby
Session Leader Plan for Boron Injector Part of Run

This run will be our first try with the boron injector during this
campaign. The primary goal is to actually see some plasma effects
when we run the injector. During the last run with the boron injector
it was only capable of injecting a 1-5 mg of boron into the machine
during a discharge, and we saw no plasma effects at all. The current
injector is capable of injecting 10 to 25 mg per discharge. 25 mg of
boron is a rough number for the replacement level needed to maintain
boronization (5000 mg of boron over about 200 discharges)

We will monitor boron lines from around the machine and use NINJA to
produce CX neutrals to view. Moly levels will be monitored. The RGA
will be checked for both boron and any impurities that might be
injected with the boron. A new camera at k-hor will view upward with
a line-of-sight outside the LCFS at material falling in from the
injector located at k-top.

If we think the boron is producing positive or at least neutral
results we will try ICRF and see if any improvement in performance can
be seen.

Shot plan:

1-3 fiducial shots w and w/o ICRF at the 2 MW level

4 inject boron at low rate (2 to 4 mg total). Check RGA and other
diagnostics for any bad effects of the boron

5-15 inject boron at high rates (10 to 20 mg / discharge)

16 fiducial with 2 MW of rf

Physics Operators Plans
Entered: Apr 12 2005 07:28:04:420PM
Author: Robert Granetz
Engineering setup for Wednesday, 13 Apr 2005

MP 348a: Boron injector tests (1/2 day)
AND
MP 333: Density limits and turbulence (1/2 day)
OR
MP 402: Locked modes at different phase (1/2day)

Session leaders: J. Irby (MP 348a) AND
((M. Greenwald, MP 333 OR (S. Wolfe, MP 402))
Physics operator: R. Granetz

Overnight ECDC in D2, bake at 60 C.

Run begins at 09:00 and ends at 17:00.

Power systems as on 1050329010.

A-coil configuration: [+Btop -Bbot -Gtop +Gbot], but power supply NOT ENABLED.

Gas Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 2 psi Ar Hybrid enabled (PG1)
leave B-side upper with whatever Hybrid disabled
fill B-main (C-side) with 30 psi D2 Hybrid enabled (PG3)

fill NINJA with 8 psi D2 Leave disabled to begin with

Torvac setup: machine gate valves to remain open during and after shot.

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

Necessary diagnostics:
MP 348a: Camera view of boron shaker; boron and moly spectroscopy
MP 333: GPC's, core and edge TS, and GPI and Halpha fluctuation arrays
if available
MP 402: GPC and SXR (for sawtooth determination of locking), HIREX
-------------------------------------------------------------------------------
ICRF Setup: All transmitters in run on at 08:30.

-------------------------------------------------------------------------------
Run plan:

For MP 348a (boron injector tests), start with segment 2 loaded from shot
1050329010, which was a recent "RF fiducial" shot.

At some point in the day, we'll switch to the second MP, which will be MP
333 unless one of the necessary diagnostics (like GPC) is not available.
The plasmas for this MP will be 0.5 MA and 6.0 T, with nebar brought up to
3.2e20 m-3 (the density limit). NINJA puffing from inboard wall might be
employed.

The A-coils will be setup as if we will switch to MP 402, but left
unpowered, so it doesn't make any difference to either of the other MP's.
NOTE that the A-coils should be put back in the standard configuration
[+Dtop -Dbot -Jtop +Jbot] for Thursday's run!!
Entered: Apr 13 2005 08:06:49:020AM
Author: Robert Granetz
Jim Irby decided to change the fiducial shot (segment 2) to 1050412003 (same as 1050406010), except that
I've removed the funny gas and density programming during the flattop. This is a 1 MA, 5.4 T, lower single
null with nl_04=0.8e20 m-2.
Entered: Apr 13 2005 09:16:32:520AM
Author: Robert Granetz
Plasma. Disrupted at t=1.35 s. Locked mode. It turns out that the A-coil power supply
was enabled and gave 1.5 kA. Lots of sparkles seen on the Boron camera,
maybe from the boron shaker.

Next shot: program A-coil current for zero kA.
Entered: Apr 13 2005 09:57:00:520AM
Author: Robert Granetz
Plasma. Full-length. nl_04=0.85e20 m-2, Ip=1.0 MA, Btor=5.4 T. A-coil current is near zero.
But there is still a locked mode starting at t=1.3 s. More speckles seen on the boron camera.

Next shot: re-arrange A-coils back to standard configuration and program them at 2 kA. Also
tweak up the early CLEARIN to see if the brief re-limiting at cross-over can be
avoided. Also turn on 2 MW of RF starting at t=0.9 s.
Entered: Apr 13 2005 10:11:08:210AM
Author: Robert Granetz
Plasma. Good shot. 2 MW of ICRF gave a long ELMy H-mode. Speckles on the boron camera.
No sign of a locked mode. Actual A-coil current is 1.5 kA. Plasma just barely briefly limited
at cross-over.

Next shot: turn off boron shaker. Also tweak early CLEARIN some more.
Entered: Apr 13 2005 10:29:11:727AM
Author: Robert Granetz
Plasma. Good shnot. Speckles pretty much disappeared from the boron view, as we hoped (since
the boron injector was turned off for this shot). Prf=2 MW. Long H-mode.

Next shot: turn boron injector on earlier and higher rate. Turn off RF.
Entered: Apr 13 2005 10:40:16:583AM
Author: Robert Granetz
Plasma. Good shot. Ohmic. Lots more from the boron shaker.

Next shot: repeat, except start the boron injection even earlier in the shot.
Keep the RF off.
Entered: Apr 13 2005 11:00:28:380AM
Author: Robert Granetz
Fizzle.

Next shot: increase Br0 offset by 0.5 mT
Entered: Apr 13 2005 11:12:07:193AM
Author: Robert Granetz
Plasma. Good shot. Ohmic. Lots of boron injection. Bruce sees a large enhancement in
boron light everywhere except in the divertor. Earl reports that Zeff also increased
slightly (by about 0.1-0.2).

Next shot: turn on RF. Move start of boron injector later, to be the same as on shot 5.
Entered: Apr 13 2005 11:14:58:287AM
Author: Robert Granetz
Plasma. Good shot. Lots of speckles in the boron camera view. Prf=2 MW.
H-mode.

Next shot: no boron injection, but leave the RF on.
Entered: Apr 13 2005 11:30:09:070AM
Author: Robert Granetz
Plasma. Good shot. Very few specks in the boron view, as expected. Prf=2 MW.
ELMy H-mode.

Next shot: PCI will turn on from 0.8-1.3 s. Boron shaker will be back on, starting early.
RF will also remain on.
Entered: Apr 13 2005 11:46:05:430AM
Author: Robert Granetz
Plasma. Good shot. Prf=2 MW. Lots of speckles on the boron camera view.
ELMy H-mode. We have PCI data starting with this shot. Bruce reports that
there was no difference in the molydenum signal between this shot (with boron)
and the previous shot (without boron). (Both had 2 MW of ICRF)

Next shot: start boron shaker even earlier (t = -0.5 s). RF on.
Entered: Apr 13 2005 11:53:06:367AM
Author: Robert Granetz
Plasma. Good shot. Prf=2 MW. ELMy H-mode. Lots of speckles.

Next shot: ramp the RF from 0.6 to 2.0 MW in order to see if the H-mode threshold
power has changed with the boron shaker.
Entered: Apr 13 2005 12:26:01:373PM
Author: Robert Granetz
Plasma. Good shot. Prf ramped from 0.6 to 2.0 MW. The H-mode started as soon as the
RF turned on (i.e. at 0.6 MW). Don't know if that's due to the boron shaker or not.

Next shot: no changes. Keep the RF ramp, but turn off J-port, so the power will be only
half as much, i.e. 0.3 -> 1.0 MW.
Entered: Apr 13 2005 12:30:10:513PM
Author: Robert Granetz
Plasma. Good shot. Prf ramped from 0.3 to 1.0 MW. H-mode was delayed to t=1.25 s, which was
at an RF power of 0.9 MW.

Next shot: repeat, no changes.
Entered: Apr 13 2005 12:45:17:453PM
Author: Robert Granetz
Plasma. Good shot. Very similar to previous shot in terms of the H-mode timing and
threshold.

Next shot: Prf = 3.0 MW (steady), starting at t=0.6 s.

Session Leader Summaries
Entered: Apr 13 2005 05:19:49:750PM
Author: Martin Greenwald
Results:

MP 333 - looking for temperature profile evolution as density
limit disruptions are approached.

We got the data we were looking for. While many of the shots
had serious marfes and poloidal detachment, there were several clean
ones at 0.5 and 0.6 MA.

At first glance, it looks like the temperature profile shrinks about
3 cm, then sits at that point for a considerable length of time before
the disruption.

It is also worth noting that the radiated power fraction can be
static throughout the high density phase of the shot. Note shot
29 for example, where Prad/Ptot ~ 0.5 for about 1 second.


Shots for further analysis:

1050413020
1050413025
1050413027
1050413029
Entered: Apr 14 2005 12:46:58:390AM
Author: Jim Irby
The primary goal of this 1/2 run day was accomplished (shots 01 to
17). The boron injector did in fact put boron into the plasma. It
was clearly seen on the k-hor boron camera and also on the
spectroscopy, both passive and CX based. Several mg of boron were
deposited into several discharges. It took up to 1 s for the boron to
make it from the top of the vessel to where it entered the plasma.
Most of the boron, at least what we could see, entered the plasma
between 20 and 30 cm above the midplane. This range of heights is
consistent with particles falling down the vertical port through the
space constrained radially between the upper ceiling tiles and the
outer edge of the port and toroidally by the upper gussets.

Between 1 and 3 MW of ICRF was coupled to the plasma during most
discharges to see if the boron had any affect on the h-mode threshold.
The threshold did not get any lower with the addition of the boron,
remaining about 900 kW. We also saw very little if any increase in
z_eff, indicating very little of the boron actually made it into the
core plasma. There was also no indication that the boron was
accumulating from the spectroscopy. Boron was not seen on the primary
RGA, though it is not clear that we should have seen elemental boron
for a time long enough to be seen. Our new RGA, setup to trend just a
few masses with much better time resolution did show boron transiently
following the shot.

To take 10 mg of boron from a solid to a completely stripped ion would
require about 60 kJ of energy from the plasma. Since we did not see
any large changes in stored energy, temperature, etc, we have another
indication that the boron remained at the edge of the plasma. The
size of the boron particles (50 to 90 um) was chosen expecting it to
penetrate approximately 1 cm inside the LCFS. However, it appears
that larger particles would have been better. Depending on the size
distribution of the particles, 10 mg of boron represents anywhere from
1000 to 4000 particles. Typically 20 to 50 boron flashes were seen on
the camera in each of 15 to 20 frames, so a large fraction of the
boron either missed the plasma, was out of sight of the camera, or was
too dim to be seen. A line filter for a visible boron line may have
helped here as would a pipe down the vertical port to guide the boron
into a more well defined location.

Finally, a change in the character of the flashes could be seen when
the ICRF was applied. The flashes went from extended several cm long
streaks that generally moves along field lines w/o rf, to shorter streaks
with more randomly directed trajectories with rf.

Physics Operator Summaries
Entered: Apr 13 2005 05:02:49:827PM
Author: Robert Granetz
Physop summary for Wednesday 13 April 2005:

We successfully ran two miniproposals today:

MP 348a: Boron injector tests (shots 1-17)
MP 333: Density limits and turbulence (shots 18-30)

The machine ran very well today, with no problems, not even with the
computers. Boron particles from the shaker were clearly observed on the
"Boron" video view at K-port, and Bruce reported significant increases in
boron spectroscopic lines everywhere except in the divertor. RF was run up
to 3 MW, which produced long, dithering/ELMy H-modes.

The density limit disruptions were run at 0.5 MA, 0.35 MA (one shot only),
0.65 MA, and 0.55 MA. Good GPC and TS core and edge temperature profiles
were obtained on many of the discharges. There were some pretty weird
features seen on the density evolution, some due to big marfes, some
possibly due to injections.

Scorecard: 30 plasmas
1 fizzle
0 duds
0 tests or no-power shot cycles
0 beam-into-gas calibration shots with B-field(s)
----------
31 total shot cycles

Session Leader Comments
Apr 13 2005 08:26:09:693AMJim Irbyboron injector has been installed on k-top and loaded with 3.5 g of boron

firewire camera has been installed at k-hor viewing upward outside of lcfs

boron injector may have a small leak: mass 28 increases from .9e-9 to 1.3e-8
when injector gatevalve is opened. This issue did not affect yesterday's run, so
we will accept it for now.
Apr 13 2005 09:18:17:960AM1050413001Jim Irbyboron injector setup for 4 pulses starting at 0.0 s (4 mg): pellets should arrive at 0.7 s

may have seen something from the injector --- had an early disuption, but it may have also
been improper setup of a-coils.

cameras are working

nice spike on 2Pi at 1.1 s

good scattered light signal from boron injector --- but boron continued to fall by longer than it should have!

Apr 13 2005 09:50:08:740AM1050413002Jim Irbyrepeat w/o a-coils

no change in boron injector settings

good shot

lots of flashes on k-hor camera

spikes on 2Pi diode and soft-xray start as early as 0.5 s

rga scope looks okay: mass 32 and 48,49 up some from last shot yesterday

h/(h+d) 3.7% at 1 s


stopped for 30 minutes to reconfigure a-coils

Apr 13 2005 10:12:41:380AM1050413003Jim Irbyshot with a-coils in proper configuration

just noticed that k-hor boron view is mirror reversed

good shot

got 2 MW of rf and nice h-mode

lots of flack on the boron camera --- beginning to believe it is boron

Apr 13 2005 10:29:44:553AM1050413004Jim Irbyboron injection delayed to 2 s for baseline shot: only 1 pulse

good shot

one one flash on the boron camera
Apr 13 2005 10:43:33:100AM1050413005Jim Irbyboron starting at -0.25, 10 Hz, 10 pulses

lots of flashes on camera starting around 0.7 s

h/(h+d) 4.5% at 1 s
Apr 13 2005 10:52:07:880AM1050413006Jim Irbyboron starts at -0.5 s, 10 HZ, 15 pulses

Bruce reports seeing much more boron everywhere except the divertor

Apr 13 2005 11:12:59:570AM1050413007Jim Irbyboron start back to -0.25 s, 10 Hz, 15 pulses --- Bruce wanted more time at beginning of shot to see
baseline changes in boron level

will have 2 MW of rf -- should help moly measurements

fizzle

Apr 13 2005 11:22:34:130AM1050413008Jim Irbyrf at 2 MW

good shot

nice h-mode

boron: -.25 s, 10 Hz, .25 duty, 15 pulses

beautiful images of boron on boron camera
Apr 13 2005 11:30:30:413AM1050413009Jim Irbyboron injector off until 2 s with one pulse

good shot

boron camera clear of boron flashes

Apr 13 2005 11:46:41:770AM1050413010Jim Irbyboron: -0.25 s, 10 Hz, .25 duty, 15 pulses

should have PCI data from 0.8 to 1.3 s

good shot

not a lot of boron flashes until late: .95 s or so?

Bruce reports lots of boron in the core/CX on pervious shots, but no
change in moly levels

h/(h+d) 4.5% at 1 s
Apr 13 2005 12:04:14:960PM1050413011Jim Irbyboron: -0.5 s, 10 Hz, .25 duty, 15 pulses

good shot

boron in plasma as early as 0.25 s

h/(h+d) 3.5 to 4.5%

communication error on RGA data

TCI baseline suspect
Apr 13 2005 12:21:50:830PM1050413012Jim Irbyboron repeat

plan to ramp ICRF power and look for threshold power level

good shot

first flash at 0.3 s, but real shower starts 0.5 s

Apr 13 2005 12:57:01:530PM1050413014Jim Irbyboron: -.5 s, 15 Hz, .25, 25 pulses

good shot

Apr 13 2005 01:31:16:780PM1050413015Jim Irbyboron repeat

only got 2 MW of rf (asked for 3 MW)

shower of boron has different character with rf --- smaller more numerous flashes

Apr 13 2005 01:42:59:123PM1050413018Martin GreenwaldFirst shot in density limit part of run

Density rises too fast, reaches density limit at 0.55 sec
disrupts at 0.84 sec
Apr 13 2005 01:52:26:063PM1050413019Martin GreenwaldSimilar to previous shot
slow down density rise on next shot
Apr 13 2005 02:14:48:860PM1050413020Martin GreenwaldBetter shot (turned off ninja)
disrupted at 1.3 seconds
density reaches just above 3e20 ~ to limit
Apr 13 2005 02:17:55:343PM1050413021Martin GreenwaldGot anomalous density rise at 0.48 second
line average density goes to 3.6e20
then marfes and disrupts
Apr 13 2005 02:38:57:797PM1050413022Martin GreenwaldShot lasts longer, marfes strongly toward end
probably detaching too
kappa has sagged to 1.5, raise for next shot
Apr 13 2005 03:15:35:063PM1050413023Martin GreenwaldDisrupts at 1.07 sec
poloidal detachments and marfes
Apr 13 2005 03:15:06:203PM1050413024Martin GreenwaldDisrupts at 1.17 sec
poloidal detachments and marfes
Apr 13 2005 03:26:31:093PM1050413025Martin Greenwaldcleaner shot
disrupts without marfe or detachement
Apr 13 2005 03:44:11:373PM1050413026Martin Greenwaldcurrent lowered to 0.35 - probably not a good idea
lots of marfes and detachments
going up in current for the next shot
Apr 13 2005 04:00:29:953PM1050413027Martin GreenwaldIp up above 0.6 MA
density reaches 4e20
disrupts cleanly without signs of disruption or detachment
Apr 13 2005 04:17:02:843PM1050413028Martin Greenwaldugly shot, early disruption
Apr 13 2005 04:30:29:327PM1050413029Martin Greenwaldgood shot
0.6 MA
nebar disrupts at 3.8e20
Apr 13 2005 04:48:43:263PM1050413030Martin Greenwaldcurrent lowered to 0.55
detaches and marfes at end of shot
Apr 13 2005 05:04:17:953PM1050413031Martin Greenwaldbad marfes again...

Physics Operator Comments
Apr 13 2005 12:56:50:437PM1050413015Robert GranetzPlasma. Good shot. Prf=2.2 MW (E didn't stay on). Dithering/ELMy H-mode.
Lots of speckles in the boron camera view.

Next shot: try again for 3 MW. Might be last shot for this MP today.
Apr 13 2005 01:14:21:140PM1050413016Robert GranetzPlasma. Good shot. Prf=3 MW, but the H-mode was very low quality.
Lots of speckles.

Next shot: start boron shaker earlier. Delay the start of RF until t=0.75. 3 MW.
This will be the last shot of MP 348a.
Apr 13 2005 01:24:48:420PM1050413017Robert GranetzPlasma. Good shot. Very similar to previous shot. Prf=3 MW. Lousy H-mode.

End of MP 348a.

Next shot: start MP 333. Ip=0.5 MA, Btor=6.0 T, nebar ramping up to 3.2e20 m-3, which is the density
limit at this current.
Apr 13 2005 01:49:43:780PM1050413018Robert GranetzPlasma. Disrupted at 0.8 s. This shot is under SSEP control and it ended up being upper null.
That is probably because I forgot to load the zeroed offset on SSEP.

Next shot: re-load the shot with the SSEP reduce to -10 mm and the offset zeroed.
Apr 13 2005 01:57:10:017PM1050413019Robert GranetzPlasma. Lower null. May have been a density limit disruption. Big marfe on the TCI.

Next shot: slow down the density ramp. Also tweak up Btor by 0.1 T
Apr 13 2005 02:08:16:500PM1050413020Robert GranetzPlasma. Good shot. The density limit disruption occurred at t=1.33 s, at the correct density
of nebar=3.2e20 m-3. The density time waveform was a little weird, but the gas feedback is
working correctly. Got good GPC and TS profiles (core and edge).

Next shot: repeat, no changes
Apr 13 2005 02:24:00:890PM1050413021Robert GranetzPlasma. Disrupted at 0.81 s, well before the density limit was reached. Very bizarre density behavior,
with a big inexplicable bump in the density around 0.5-0.6 s. NINJA was not puffing.

Next shot: try again, no changes
Apr 13 2005 02:40:36:970PM1050413022Robert GranetzPlasma. Good shot. Density behavior looked good on this shot. Good GPC and TS profiles.

Next shot: program ZXL to ramp down by 2 cm in order to keep the elongation
from decreasing during the shot.
Apr 13 2005 03:06:50:420PM1050413023Robert GranetzPlasma. Not a pretty looking shot due to all the marfing, I think. At EF1 cross-over the plasma
briefly becomes limited. Elongation stays constant except for the notch when it briefly limits.

Next shot: repeat, no changes.
Apr 13 2005 03:22:34:267PM1050413024Robert GranetzPlasma. Ugly. More bizarre density features. Lots of early hard x-rays.

Next shot: try one more time at these parameters. Also tweak up the early
gas puffing.
Apr 13 2005 03:29:46:920PM1050413025Robert GranetzPlasma. Good shot. Disrupted at the proper density.

Next shot: drop Ip to 350 kA and nebar to 2.0e20 m-3.
Apr 13 2005 03:40:30:450PM1050413026Robert GranetzPlasma. Lots of density features.

Next shot: raise Ip to 0.65 MA and nebar up to 4e20 m-3.
Apr 13 2005 03:57:58:267PM1050413027Robert GranetzPlasma. Good shot. 0.62 MA, 6.0 T, nebar about 4e20 m-3 at the density limit disruption,
as expected.

Next shot: repeat, no changes
Apr 13 2005 04:26:02:063PM1050413028Robert GranetzPlasma.

Stop to get one of Amanda's GPC2 crates back online.

Next shot: no changes.
Apr 13 2005 04:38:28:657PM1050413029Robert GranetzPlasma. Good shot. Disrupted at t=42 s, around the density limit. Got GPC2 data this time.

Next shot: "Good question," said Martin. Drop the current to 0.55 MA and the density
accordingly.
Apr 13 2005 04:51:39:140PM1050413030Robert GranetzPlasma. Good shot. Disrupted at t=1.17 s, at about the density limit for this current.

Next shot: repeat, no changes. This will be the last shot.
Apr 13 2005 05:01:03:687PM1050413031Robert GranetzPlasma. Good shot.

End of run.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:03:44:147AMPlasmaOk
209:18:43:977AMPlasmaOk
310:02:01:867AMPlasmaOk
410:14:41:583AMPlasmaOk
510:30:28:990AMPlasmaOk
610:43:06:147AMPlasmaOk
710:55:41:630AMPlasmaOk
811:08:19:710AMPlasmaOk
911:21:11:367AMPlasmaOk
1011:33:51:617AMPlasmaOk
1111:46:51:803AMPlasmaOk
1212:08:40:130PMPlasmaOk
1312:23:02:953PMPlasmaOk
1412:36:31:453PMPlasmaOk
1512:49:00:017PMPlasmaOk
1601:05:52:717PMPlasmaOk
1701:18:11:000PMPlasmaOk
1801:32:35:937PMPlasmaOk
1901:47:09:953PMPlasmaOk
2001:59:35:017PMPlasmaOk
2102:12:19:767PMPlasmaOk
2202:28:09:920PMPlasmaOk
2302:56:23:687PMPlasmaOk
2403:11:44:733PMPlasmaOk
2503:24:12:313PMPlasmaOk
2603:36:49:420PMPlasmaOk
2703:52:35:390PMPlasmaOk
2804:07:54:250PMPlasmaOk
2904:27:54:420PMPlasmaOk
3004:44:34:233PMPlasmaOk
3104:57:13:720PMPlasmaOk