Alcator C-Mod Run 950526 Information

Miniproposals

Miniproposal: 104

Date Filed: 3/13/1995

Title: Investigation of plasma flows using gas injection plumes

First Author: Bruce Lipschultz

Session Leader: Gary McCracken (shots 1-38)

Operators
Session leader(s):	Gary McCracken
Physics operator(s):	Robert Granetz
Engineering operator(s):	Joe Daigle,Frank Silva

Engineering Operator Run Comment
Granetz

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:13:803PM

Author: To Be Determined

Session Leader Run Summary 9505026

Engineering operator: F Silva/J Daigle
Physics operator: R Granetz
Session Leader: G M McCracken

Run for mini-proposals #104
Objectives: Inject impurities at the inner wall and at the divertor with the
NINJA system and follow the spatial spreading with the CCD cameras and filters
from B-side and B-top. Compare with limiter plasma. Measure impurity screening
in parallel

A very successful day. We started off with a lower x-point discharge
and puffed CH4 from the inner wall capillary (B16-001) over a range of
densities from nl04= 0.9 to 1.8e20 m^-2. CII and CIII were observed with the
B-side CCD camera in alternate discharges: in both cases the flow was clearly
seen going towards the divertor. This is in contrast to the results obtained
on 950414 when the flow reversed direction at a density of 1.5e20. The flow
direction generally reverses at the start of current rampdown as the plasma
moves back to being limited rather than diverted. Detachment was observed on
shots with densities nl04=1.3e20 or higher. The detachment occurred before
the CH4 was injected.
An upper X-point discharge was then set up with some difficulty, there
being a series of disruptions. The reasons for this were not very clear, but
it may have been due to the need for conditioning the upper divertor surfaces.
Data was eventually taken for densities from 0.9e20 up to 1.7e20. With the
upper X-point we also injected CH4 from capillaries B26-019 (lower private flux
region) and B22-022 (lower inner cone above the inner nose), shots 025 and
029. In both cases clear evidence of toroidal flow was observed in positions
which, with the upper X-point , should be close to the stagnation point. Good
FSP data were obtained for these discharges, which should allow us to compare
the flow estimated from the plumes with that estimated from the ratio of the
parallel and antiparallel Isat on the FSP
Next we studied the injection of CH4 from B16-001 into inner-wall,
limited discharges. As was to be expected the impurities were ionised rapidly
and the CII distribution was a small (10-20 mm) diameter symmetric blob. The
CIII appeared to spread all round the inner column but was also roughly
symmetric. CH4 was injected from the the B-side lower valve for the limiter
and lower x-point discharges to compare with the NINJA injections.
Many of the shots will be useful for screening estimates since in
general only one valve was used for each condition. Comparisons will be
possible for different injection conditions, different densities and different
plasma configurations, limiter, upper x-point and lower x-point. In general
good data were obtained on the midplane CII monitor at C-port and a consistent
set of data were measured with the McPherson (CVI) and Chromex spectrometers
(CII and CIII). The signals on the spectrometerrs increased very little when
the CH4 was injected, but good background shots were taken for most cases so
that at least upper limits to the screening efficiency should be obtained.
Good FSP data obtained for most conditions, including Limiter
discharges.

Shot summary:
CH4 plenum pressure 6.2 psi (330 torr) throughout. NINJA valves triggered at
0.45 s for shots #02 to 07 and at 0.55 s therafter. Pulse length 0.3 s. When
the B-side lower valve was used it was triggered from 0.6 to 0.95 s. the plenum
pressure in this case was 3.4psi.
The filter stated below refers only to the B-side camera. The B-top camera was
only recorded for a limited number of shots, eg 025,029,036, when puffing at the
bottom. The CII filter was used.

Lower X-point
01. Good background shot, No CH4, nl04=0.8e20.
02. Good shot, CH4 injected at B16-001 and B22-022, CII filter, nl04=1e20.
03. Good shot, CH4 injected at B16-001 only, CIII filter, nl04=1e20.
04. Disruption at 0.6 s.
05. Good background shot, No CH4, nl04=01.3e20.
06. Good shot, CH4 injected at B16-001, CII filter, nl04=1.3e20.
07. Good shot, CH4 injected at B16-001, CIII filter, nl04=1.3e20.
08. Good background shot, No CH4, nl04=1.64e20.
09. Good shot, CH4 injected at B16-001, CIII filter, nl04=1.64e20.
10. Good shot, CH4 injected at B16-001, CII filter, nl04=1.64e20
11. Good shot, CH4 injected at B16-001, CII filter, nl04=1.76e20: disrupted at
0.85 s.
35. Good shot, CH4 injected at B-side lower, CIII filter, nl04=1.10e20.
36. Good shot, CH4 injected at B26-019, CII filter, nl04=1.24e20. Toroidal
flow just barely detectable. Compare with shot 025 with upper X-point.
37. Good background shot, No CH4, nl04=1.15e20.

Upper X-point
12. Disrupted at 0.4 s.
13. Disrupted at 0.96 s, No CH4.
14. Disrupted at 0.4 s.
15. Disrupted at 0.4 s.
16. Fizzle.
17. Good background shot, No CH4, nl04=0.83e20.
18. Good shot, CH4 injected at B16-001, CII filter, nl04=0.87e20.
19. Good shot, CH4 injected at B16-001, CIII filter, nl04=0.88e20.
20. Disrupted at 0.4 s.
21. Good shot, CH4 injected at B16-001, CIII filter, nl04=1.28e20.
22. Good shot, CH4 injected at B16-001, CII filter, nl04=1.3e20.
23. Good background shot, No CH4, nl04=1.21e20.
24. Disrupted at 0.4 s.
25. Good shot, CH4 injected at B26-019, CII filter, nl04=1.24e20. Toroidal
flow.
26. Good shot, CH4 injected at B16-001, CII filter, nl04=1.7e20.
27. Good shot, CH4 injected at B16-001, CII filter, nl04=1.66e20.
28. Fizzle.
29. Good shot, CH4 injected at B22-022, CII filter, nl04=1.27e20. Toroidal
flow.

Limiter shots
30. Good shot, CH4 injected at B16-001, CII filter, nl04=1.20e20: disrupted at
0.85 s
31. Good shot, CH4 injected at B16-001, CIII filter, nl04=1.21e20.
32. Disrupted at 0.55 s.
33. Good shot, CH4 injected at B-side lower, CIII filter, nl04=1.17e20.
34. Died early.
38. Good background shot, No CH4, nl04=1.15e20.

Physics Operator Summaries

Entered: Jul 7 2004 04:36:54:537PM

Author: To Be Determined

Physics operator's summary for run 950526.

MP #104, Investigation of Plasma Flows Using Gas Injection Plumes

SL: G. McCracken
PO: R. Granetz

Primary purpose: Inject CH4 and He at the inner wall and divertor with
NINJA system and study plumes in plasmas with B x grad B
drift down. Compare to data from 950414, when the B x grad B
drift was reversed. We will run lower x-pt's, upper x-pt's,
and limited plasmas, at several densities and several puffing
locations.

Secondary purpose: Compare limiter/divertor screening of methane, which is a
non-recycling impurity.

Summary: Today's run plan was very challenging to say the least. Fortunately
things went very well, and we were able to get good methane plume
data in lower x-pt, upper x-pt, and limited plasmas at a range of
densities. In addition, we got good data for comparing the carbon
screening efficiency of limited and lower x-pt plasmas. The session
leader's report presents some of the plume physics results. I have
looked at the carbon screening comparison and find that there is a
factor of 2 difference. (Thanks to J.T. and Gary for showing me the
CVI and CII data.) The shots of relevance for the screening study
are 033 (limited w/methane), 035 (lower x-pt w/methane), 037 (lower
x-pt, no methane), and 038 (limited, no methane). We did not have
time to do any helium studies today. Also see shot 031 for an
example of a limited plasma with methane puffing directly into the
boundary using the NINJA inboard midplane location. It has much
higher carbon signals than the shots that had methane puffed from the
B-side-lower valve.

001-011 Diverted, lower x-pt
012-029 Diverted, upper x-pt
030-033 Limited
034-037 Diverted, lower x-pt
038 Limited

Statistics: 36 Plasmas
2 Fizzles
0 Duds
Power supply problems caused disruptions on 2 shots.
The I^2*t circuit was enabled today.

Setup: Lower x-pt: 950512027, with density changed to nl_04=0.8e20 m-2,
Upper x-pt: 950322029, with density changed to nl_04=0.8e20 m-2,
Limited : 950519021, with density changed to nl_04=1.0e20 m-2.

To speed up PCS operations, I setup a PCS the evening before this
run with segments 2,3, & 4 loaded with the three configurations,
respectively.

Engineering preparations:

Setup up from shot 950512027 (including commutation resistors,
TF start time, TF current, etc).
Normal ECDC in D2.
Set pre-fill at 1.8e-5 torr of D2.
Fill A-side with D2 at 19-20 psi.
Fill B-side-lower with methane at 3 psi, BUT LEAVE DISABLED!
Fill the NINJA plenum with methane at 5 psi.
All other gas valves should be disabled as well.

Shot 01 -- Setup for a lower x-pt baseline shot. No methane puffing.
Plasma, good shot. Density oscillated a bit.

Next shot: repeat with NINJA system puffing methane from the
inboard midplane location and from the inner divertor nose location.

Shot 02 -- Plasma, good shot. Methane plumes were seen (CII). On request from
Brian, we will tweak upper and lower x-pt positions on the next
shot. Fast scanning probe fired on this shot.

Next shot: tweak upper and lower x-pt locations, and puff methane
from midplane only.

Shot 03 -- Plasma, good shot. Good plume (CIII).

Next shot: tweak upper x-pt another 5 mm up. NINJA puff from both
locations enabled.

Shot 04 -- Plasma, disrupted at 0.59 s. VDE. Probably not due to excessive
radiation. Elongation was very high.

Next shot: lower ZCUR by 5 mm, and turn off methane in order to
get a background shot.

Shot 05 -- Plasma, good shot. Density got to the requested value of 1.3e20 m-2.
Zxray did move down.

Next shot: NINJA methane puff from midplane.

Shot 06 -- Plasma, good shot. Good plume data (CII). Jim Terry reports
that carbon background level is gradually rising from shot to shot.

Next shot: NINJA methane puff from midplane, different filter.

Engineering has enabled the I^2*t circuit starting with the next shot.

Shot 07 -- Plasma, good shot. Good plume data (CIII).

Next shot: increase density to nl_04=1.6e20 m-2. Turn off methane.

Shot 08 -- Plasma, good shot. Density got to nl_04=1.6e20 m-2 by 0.75 s.

Next shot: enable NINJA methane puff.

Shot 09 -- Plasma, good shot. Got plume data (CIII).

Next shot: NINJA methane puff with different filter.

Shot 10 -- Plasma, good shot. Good plume data (CII).

Next shot: raise density to nl_04=1.8e20 m-2. Also puff methane.

Shot 11 -- Plasma, disrupted at 0.86 s. Got good plume data anyway.

Next shot: change to upper x-pt at nl_04=0.8e20 m-2. No methane
puffing.

Switching to upper x-pt configuration starting with the next shot.

Shot 12 -- Plasma, disrupted at 0.41 s. VDE. Upper x-pt.

Next shot: slow down the current rise with a little tweak.

Shot 13 -- Plasma, disrupted at 0.96 s. VDE. Some hard x-rays. Brian wants
the plasma lowered by 1 cm so the scanning probe can reach, but
we're near the vertical stability limit.

Next shot: Turn on EF2_BY_EF4 control, lower ZCUR and ZXU by 1 cm,
increase RCUR by 2 mm, and raise pre-fill from 1.8 to 2.0e-5 torr.
Also turn on methane puff.

Shot 14 -- Plasma, disrupted at 0.42 s. VDE. No hard x-rays.

Next shot: raise ZCUR by 5 mm. Methane puff enabled.

Shot 15 -- Plasma, disrupted at 0.41 s. TF and PF crowbarred. Vinnie thinks
the OH2L had a fault which caused the disruption.

Next shot: repeat with no changes.

There's a break in the run while a fuse is replaced in the TF supply.

Shot 16 -- Fizzle.

Next shot: repeat with no changes.

Shot 17 -- Plasma, good shot. Upper x-pt. No methane. Brian reports that
the fast scanning probe will be able to reach this plasma.

Next shot: enable NINJA methane puff.

Shot 18 -- Plasma, disrupted at 0.99 s, VDE. Good plume data. The plume
reversed direction. Good FSP data.

Next shot: another NINJA methane puff, with different filter.

Shot 19 -- Plasma, good shot. Good plume data. Good FSP data.

Next shot: raise density to nl_04=1.2e20 m-2, with methane puff.

Shot 20 -- Plasma, disrupted at 0.40, which is before I made any change in
the density programming. VDE.

Next shot: repeat with no changes.

Engineering pulled out a slew-rate limiting circuit board from OH1 between
shots.

There was a delay due to a problem with the STATE machine.

Shot 21 -- Plasma, good shot. Good plume data. Density made it to 1.2e20 m-2.

Next shot: repeat with different filter.

Engineering re-inserted the slew-rate limiting circuit board into OH1 between
shots.

Shot 22 -- Plasma, good shot. Good plume data, good probe data.

Next shot: repeat with no methane, to get a background shot.

Change TF invert time from 1.6 to 1.1 s in order to speed up rep rate.

Shot 23 -- Plasma, good shot. Good baseline shot.

Next shot: NINJA methane puff from bottom divertor (private flux
zone).

Shot 24 -- Plasma, runaway screamer, disrupted at 0.39 s.

Next shot: raise pre-fill from 2.0 to 2.2e-5 torr. Puff methane
from private flux zone.

Shot 25 -- Plasma, good shot.

Next shot: raise density to nl_04=1.6e20 m-2. Puff methane from
inboard midplane.

Shot 26 -- Plasma, good shot. Density made it to 1.6e20 m-2. Good plume data,
Good FSP data.

Next shot: repeat with NINJA methane puff and different filter.

Shot 27 -- Plasma, disrupted at 0.83 s. VDE. Probably due to molybdenum
injection. Got plume data.

Next shot: reduce density to nl_04=1.2e20 m-2 and puff from the
bridge of the divertor. Still upper x-pt configuration.

Shot 28 -- Fizzle.

Next shot: repeat with no changes.

Shot 29 -- Plasma, good shot. Good plume data and FSP data. Nl_04=1.2e20 m-2.
This is the last upper x-pt configuration in this series.

Next shot: change to limiter plasma configuration, with
nl_04=1.0e20 m-2, and NINJA methane puff from inboard midplane.

Shot 30 -- Plasma, limited, disrupted at 0.85 s, maybe due to more carbon
getting in. Plume was more circular than plum-ish.

Next shot: repeat with different filter.

Shot 31 -- Plasma, good shot. Good data. Carbon brightness is a factor of
4 to 5 higher than diverted plasmas.

Next shot: raise density to nl_04=1.5e20 m-2. Continue methane
puffing from inboard midplane.

Shot 32 -- Plasma, disrupted at about 0.45 s. Looks like it got very dirty
and resistive.

Next shot: reduce density back to nl_04=1.0e20 m-2, turn off
NINJA, but puff methane through B-side-lower. (B-side-lower plenum
pressure is 3.4 psi)

Shot 33 -- Plasma, good shot. Limited, with methane puff from B-side-lower
valve. This is the shot I need for screening comparison on non-
recycling impurities. nl_04=1.1e20 m-2.

Next shot: switch back to lower x-pt, with methane puff from
B-side-lower valve.

Shot 34 -- Plasma, disrupted at 0.23 s, prior to becoming diverted. Disruption
was caused by an OH2L fault.

Next shot: repeat with no changes.

Shot 35 -- Plasma, good shot. Diverted, lower x-pt, with methane puff from
B-side-lower valve. This is the other shot I need for screening
comparison of non-recycling impurity. nl_04=1.1e20 m-2.

Next shot: repeat with NINJA puffing of methane from the private
flux zone. B-side-valve is disabled.

Comparison of CII signal shows a factor of two difference between the limiter
plasma (033) and the diverted plasma (035). The CII signal is a measure of
carbon flux through the edge. Measurements of CVI brightness taken
by the McPherson show a factor of 2-3 difference.

Shot 36 -- Plasma, good shot. Lower x-pt, with methane puff from private
flux zone.

Next shot: repeat, but with no methane puffing, to get a baseline.
Also change TF invert time from 1.1 to 0.9 s so Amanda can get
a calibration.

Shot 37 -- Plasma, good shot. No methane puffing. Good baseline shot for
diverted, lower x-pt configuration. nl_04=1.1e20 m-2.

Next shot: switch to limiter configuration again, but without
any methane puffing, to get a baseline shot at nl_04=1.0e20 m-2.
TF invert time moved back to 1.1 s.

Shot 38 -- Plasma, good shot. No methane puffing. Good baseline shot for
limiter configuration. nl_04=1.1e20, with some wobbles. Brian
got some fast scanning probe data.

Using these two baseline shots (037 and 038) with the two methane shots (033
and 035), Jim Terry reports a factor of two difference in CVI brightness.

End of run.

Session Leader Comments

May 26 1995 08:43:49:090AM Gary McCracken Study of plasma flows using gas injection plumes (MP 104)

The plan is to generally repeat the program of CH4 injection obtained
on run 950414 but this time with grad B drift down. The CH4 will be
injected principally from the NINJA system at the inner wall midplane
and observed with the CCD cameras using CII CII filters. We will
compare the X-point at the top and at the bottom. We will also look
at the effect of injecting into limiter discharges.
We plan to use these shots to measure carbon screening and to
use B-side lower injection as well as different NINJA positions

May 26 1995 05:33:11:530PM Gary McCracken Brief summary: Good day; We did a density scan with a lower x-point
plasma from nl04=0.8 to 1.8e20 with methane injection through
the inner wall capillary (B16-001)
CII and CI plumes were observed always going towards the divertor
target. This is different to the results from the run950414 with the
grad B drift upwards, where we got the flow reversing at high density
We then did upper X-point discharges.We again got a density scan and
the flow was always towards the upper divertor
We also did some puffing through the lower divertor capillaries
B26-019 and B22-022 with upper X-point. Interestingly we saw clear
toroidal flow viewing from the B-top camera. No apprecaible signal was
observed from the B26-019 cap when the X-point was down

May 26 1995 08:49:04:090AM 950526001 Gary McCracken shot 001

Good shot. nlo40.8e20. Inside and outside gaps good.
Plasma position for FSP very good.

Plan to inject CH4 through NINJA valves B16-001 and B22-022 next shot

May 26 1995 09:05:31:040AM 950526002 Gary McCracken shot 002
Inject CH4 through NINJA valves B16-001 and B22-022 CII filter
Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms
Good shot; CH4 injected and observed both on B-side camera and on
A-side (unfiltered) camera. It is clearly seen from both valves and
is quite bright.
Outer strike point at FMP probe 4

May 26 1995 09:18:30:810AM 950526003 Gary McCracken shot 003
Inject CH4 through NINJA valves B16-001 only CIII filter
Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms
Good shot; CH4 injected and observed on B-side camera .
Intensity looks better than previously observed with the
CIII filter. The plasma is clearly being fuelled by the NINJA
system and the density is going up beyond the value demanded
nl04=1e20

May 26 1995 09:32:26:280AM 950526004 Gary McCracken shot 004
Inject CH4 through NINJA valves B16-001 and B22-022 CII filter
Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms
Disruption at 0.6 s CH4 observed on B-side camera for 2 or 3
frames.
Asked for nlo4=1.3e20 reached 1.15e20 before disruption.
We will have a background shot without any CH4 next shot

May 26 1995 09:49:33:830AM 950526005 Gary McCracken shot 005
NO CH4 injected. Good shot
Asked for nlo4=1.3e20 and got it.
We will go back to gas puffing next shot

May 26 1995 10:06:37:560AM 950526006 Gary McCracken shot 006
CH4 injected.B16-001 only, conditions as before, CIII filter
Good shot. Clear plume. nl04=1.38e20 nice and constant
It is clear in both this shot and 005 that we are getting detachment
at 0.53 s, up to probe 5. shot 005 was without methane.
The strike point is on probe 3 to 4, moving up towards the end of
the shot

May 26 1995 10:18:57:580AM 950526006 Gary McCracken shot 006
CORRECTION :USED CII FILTER THIS SHOT NOT CIII AS PREVIOUSLY STATED

May 26 1995 10:17:25:430AM 950526007 Gary McCracken shot 007
CH4 injected.B16-001 only, conditions as before, CIII filter
Plume observed but much weaker. nl04=1.4e20

May 26 1995 10:32:17:050AM 950526008 Gary McCracken shot 008
Increased demand density to 1.6e20.
No methane injected to obtain background at higher density.
Good shot; nl04 =1.64e20

May 26 1995 10:45:52:000AM 950526009 Gary McCracken shot 009
CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s).
B16-001 valve only ;plenum pressure still 6.15 psi
Good shot; CIII plume clearly towards the divertor still,
though faint. No sign of reversing direction at high density
as seen on 950414 run
nl04 =1.69e20

May 26 1995 10:56:49:130AM 950526010 Gary McCracken shot 010
CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s).
B16-001 valve only ;plenum pressure still 6.15 psi
CII filter (last shot CIII filter)
Good shot; CII plume still downwards ;bright but possibly
decaying faster along the field line. nl04=1.65e20

May 26 1995 11:15:39:060AM 950526011 Gary McCracken shot 011
Density demand raised to 1.8e20
CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s).
B16-001 valve only ;plenum pressure 6.15 psi CII filter
Good shot until 0.85 s then disrupted CII plume still downwards,
looks fine nl04=1.76e20 at disruption, still rising

May 26 1995 11:53:53:090AM 950526013 Gary McCracken shot 013
No methane injection; nl04 0.8e20
Disrupted 0.95 s

May 26 1995 11:49:35:760AM 950526014 Gary McCracken shot 012
Change to upper X-point
Reduce density to 0.8e20, no methane puff.
Disrupted at 0.4 s; not clear why.

May 26 1995 11:59:20:620AM 950526014 Gary McCracken shot 014
Methane injection B16-001 valve, timing and pressure as above
Tried to improve plasma elongation and position for FSP
Disrupted 0.45 s; nl04 =0.6e20 at disruption. Gas in after disruption
but bright spots at capillaries one frame before disruption. No
obvious explanation.

May 26 1995 12:35:07:880PM 950526015 Gary McCracken shot 015
No methane injection
Raised plasma and reduced elongation
Early disruption 0.4 s.

May 26 1995 12:35:35:170PM 950526015 Gary McCracken shot 016
No methane injection
Fizzle

May 26 1995 12:52:30:260PM 950526016 Gary McCracken shot 016
No methane injection
Fizzle

May 26 1995 12:54:41:140PM 950526017 Gary McCracken shot 017
No methane injection ;Background shot
Good plasma with upper X-point nl04 =0.84e20

May 26 1995 01:02:15:460PM 950526018 Gary McCracken shot 018
Methane injection , CII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure still 6.15 psi
Good plasma with upper X-point nl04 =0.84e20.
CII plume clearly visible with reversed direction, as expected.

May 26 1995 01:17:46:910PM 950526019 Gary McCracken shot 019
Methane injection , CIII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure still 6.15 psi
Good shot; Clear CIII plume towards upper divertor, although faint.
It is however more symmetric than the CII plume
Clear step up on CII signal on C-port at 0.68 s, on this and previous
pulse, compared with shot 17 which had no methane injected

May 26 1995 01:24:21:800PM 950526020 Gary McCracken shot 020
Methane injection , CIII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi
Disrupted at 0.4 s

May 26 1995 01:36:38:060PM 950526021 Gary McCracken shot 021
Try repeat of shot 20
Methane injection , CIII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi
Did not fire

May 26 1995 01:45:58:110PM 950526021 Gary McCracken shot 021
Try again repeat of shot 20
Methane injection , CIII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi
Good shot; clear but faint CIII plume towards upper divertor
Note plume reverses around the time of current ramp down.

May 26 1995 01:54:14:800PM 950526022 Gary McCracken shot 022
Repeat shot
Methane injection , CII filter; B16-001 only;
Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi
Good shot; clear CII plume towards upper divertor
Plume again reverses around the time of current ramp down.

May 26 1995 02:10:08:740PM 950526023 Gary McCracken shot 023
Repeat shot
No methane injection, background shot
Good shot nl04= 1.22e20. Very nice flat CII signal from C-port

May 26 1995 02:22:29:490PM 950526024 Gary McCracken shot 024
Methane injection, B26-019 at lower divertor;
Trigger at 0.55s for 0.3 s ; 6.1 psi
Disruption at 0.4 s Not clear why

t

May 26 1995 02:39:30:680PM 950526025 Gary McCracken shot 025
Methane injection, B26-019 at lower divertor; CII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Good shot nl04 1.29 ; CII plume; Faint, but toroidal flow observed on
the B-top camera looking at B26-019

May 26 1995 02:45:13:220PM 950526026 Gary McCracken shot 026
Methane injection, B16-001 at inner wall; CII filter, higher density
Trigger at 0.55s for 0.3 s ; 6.1 psi
Good shot ; nl04 1.29 ; CII plume;

May 26 1995 02:53:13:260PM 950526027 Gary McCracken shot 027
Methane injection, B16-001 at inner wall; CIII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi

Disruption at 0.82 s,but got the CIII plume, faint but
clearly towards the upper divertor ; nl04 1.62

May 26 1995 02:55:23:880PM 950526027 Gary McCracken shot 027
Methane injection, B16-001 at inner wall; CIII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi

Disruption at 0.82 s,but got the CIII plume, faint but
clearly towards the upper divertor ; nl04=1.62

May 26 1995 03:03:33:970PM 950526028 Gary McCracken shot 028
Methane injection, B22-022 at inner upper divertor with X-point at top
to compare with shot 25 ,(puff from B26-019); CII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Fizzle

May 26 1995 03:20:46:040PM 950526029 Gary McCracken shot 029
Methane injection, B22-022 at inner upper divertor with X-point at top
to compare with shot 25 ,(puff from B26-019); CII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Very clear flow along the field observed in the B-top camera
Good FSP data obtained. This should allow us to compare the flow
derived from the plume with that derived from the scanning probe.

May 26 1995 03:29:55:710PM 950526030 Gary McCracken shot 030
Changed to limited plasma
Methane injection, B16-001 at inner wall ; CII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Disrupted at 0.85 s, but can see the CII at the midplane.
Very localized symmetric spot, presumably because the
ionization is so fast when it enters in the core plasma

May 26 1995 03:43:34:840PM 950526031 Gary McCracken shot 031
Limited plasma
Methane injection, B16-001 at inner wall ; CIII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Good shot ; CIII bright light spreads uniformly in both directions

May 26 1995 03:52:32:370PM 950526032 Gary McCracken shot 032
Limited plasma
Methane injection, B16-001 at inner wall ; CIII filter
Trigger at 0.55s for 0.3 s ; 6.1 psi
Repeat shot except higher density
Disrupted at 0.45 s due to plasma being too resistive. Why?

May 26 1995 04:09:15:280PM 950526033 Gary McCracken shot 033
Limited plasma
Methane injection, through B-side lower; 0.6 to 0.95 s;
Plenum pressure 3.4 psi. CIII filter
Good shot . Clear signal on CII at C-port

May 26 1995 04:10:13:950PM 950526033 Gary McCracken shot 033
Limited plasma
Methane injection, through B-side lower; 0.6 to 0.95 s;
Plenum pressure 3.4 psi. CIII filter
Good shot . Clear signal on CII at C-port

May 26 1995 04:14:46:450PM 950526034 Gary McCracken shot 034
Lower X-point to compare with previous limited plasma
Methane injection, through B-side lower; 0.6 to 0.95 s;
Plenum pressure 3.4 psi. CIII filter
Died early; Power supply problem on lower OH2

May 26 1995 04:27:22:960PM 950526035 Gary McCracken shot 035
Lower X-point to compare with previous limited plasma
Methane injection, through B-side lower; 0.6 to 0.95 s;
Plenum pressure 3.4 psi. CIII filter
Good shot clear signal on Cii at C-port. the delta CIi is about
half of the value in the limiter shot

May 26 1995 04:45:04:930PM 950526036 Gary McCracken shot 036
Lower X-point
Methane injection, through B26-019; Trigger at 0.55 s for 0.3 s;
Plenum pressure 6.0 psi. CII filters
Good shot ; nl04 =1.1e20
Very faint signal on the B-top camera but not certain it comes
from the gas puffing at the PFZ

May 26 1995 04:51:21:970PM 950526037 Gary McCracken shot 037
Lower X-point
No Methane injection, Backgroundshot for spectroscopy
Good shot; nl04=1.08e20. Nice low flat CII background signal

May 26 1995 05:12:23:790PM 950526038 Gary McCracken shot 038
Limiter shot; Another background shot for spectroscopy
No Methane injection,
Good shot; nl04=1.15e20.

Physics Operator Comments

May 25 1995 06:27:03:800PM Robert Granetz MP #104, Investigation of Plasma Flows Using Gas Injection Plumes

Primary purpose: Inject CH4 and He at the inner wall and divertor with
NINJA system and study plumes in plasmas with B x grad B
drift down. Compare to data from 950414, when the B x grad B
drift was reversed. We will run lower x-pt's, upper x-pt's,
and limited plasmas, at several densities and several puffing
locations.

Secondary purpose: Compare limiter/divertor screening of methane, which is a
non-recycling impurity

May 25 1995 06:27:33:940PM Robert Granetz Setup: Lower x-pt: 950512027, with density changed to nl_04=0.8e20 m-2,
Upper x-pt: 950322029, with density changed to nl_04=0.8e20 m-2,
Limited : 950519021, with density changed to nl_04=1.0e20 m-2.

To speed up PCS operations, I setup a PCS the evening before this
run with segments 2,3, & 4 loaded with the three configurations,
respectively.

Engineering preparations:

Setup up from shot 950512027 (including commutation resistors,
TF start time, TF current, etc).
Normal ECDC in D2.
Set pre-fill at 1.8e-5 torr of D2.
Fill A-side with D2 at 19-20 psi.
Fill B-side-lower with methane at 3 psi, BUT LEAVE DISABLED!
Fill the NINJA plenum with methane at 5 psi.
All other gas valves should be disabled as well.

May 26 1995 08:56:56:830AM 950526001 Robert Granetz Shot 01 -- Setup for a lower x-pt baseline shot. No methane puffing.
Plasma, good shot. Density oscillated a bit.

Next shot: repeat with NINJA system puffing methane from the
inboard midplane location and from the inner divertor nose location.

May 26 1995 09:05:09:530AM 950526002 Robert Granetz Shot 02 -- Plasma, good shot. Methane plumes were seen. On request from
Brian, we will tweak upper and lower x-pt positions on the next
shot.

Next shot: tweak upper and lower x-pt locations, and puff methane
from midplane only.

May 26 1995 09:20:49:140AM 950526003 Robert Granetz Shot 03 -- Plasma, good shot. Good plume (CIII).

Next shot: tweak upper x-pt another 5 mm up. NINJA puff from both
locations enabled.

May 26 1995 09:34:35:090AM 950526004 Robert Granetz Shot 04 -- Plasma, disrupted at 0.59 s. VDE. Probably not due to excessive
radiation. Elongation was very high.

Next shot: lower ZCUR by 5 mm, and turn off methane in order to
get a background shot.

May 26 1995 09:50:45:090AM 950526005 Robert Granetz Shot 05 -- Plasma, good shot. Density got to the requested value of 1.3e20 m-2.
Zxray did move down.

Next shot: NINJA methane puff from midplane.

May 26 1995 10:03:08:730AM 950526006 Robert Granetz Shot 06 -- Plasma, good shot. Good plume data (CIII). Jim Terry reports
that carbon background level is gradually rising from shot to shot.

Next shot: NINJA methane puff from midplane, different filter.

May 26 1995 10:03:28:250AM 950526006 Robert Granetz Engineering has enabled the I^2*t circuit starting with the next shot.

May 26 1995 10:14:06:780AM 950526007 Robert Granetz Shot 07 -- Plasma, good shot. Good plume data (CIII).

Next shot: increase density to nl_04=1.6e20 m-2. Turn off methane.

May 26 1995 10:30:10:470AM 950526008 Robert Granetz Shot 08 -- Plasma, good shot. Density got to nl_04=1.6e20 m-2 by 0.75 s.

Next shot: enable NINJA methane puff.

May 26 1995 10:46:05:040AM 950526009 Robert Granetz Shot 09 -- Plasma, good shot. Got plume data (CIII).

Next shot: NINJA methane puff with different filter.

May 26 1995 10:51:51:760AM 950526010 Robert Granetz Shot 10 -- Plasma, good shot. Good plume data (CII).

Next shot: raise density to nl_04=1.8e20 m-2. Also puff methane.

May 26 1995 11:08:27:120AM 950526011 Robert Granetz Shot 11 -- Plasma, disrupted at 0.86 s. Got good plume data anyway.

Next shot: change to upper x-pt at nl_04=0.8e20 m-2. No methane
puffing.

May 26 1995 11:27:19:930AM 950526012 Robert Granetz Shot 12 -- Plasma, disrupted at 0.41 s. VDE.

Next shot: slow down the current rise with a little tweak.

May 26 1995 11:44:41:820AM 950526013 Robert Granetz Shot 13 -- Plasma, disrupted at 0.96 s. VDE. Some hard x-rays. Brian wants
the plasma lowered by 1 cm so the scanning probe can reach, but
we're near the vertical stability limit.

Next shot: Turn on EF2_BY_EF4 control, lower ZCUR and ZXU by 1 cm,
increase RCUR by 2 mm, and raise pre-fill from 1.8 to 2.0e-5 torr.
Also turn on methane puff.

May 26 1995 11:58:42:710AM 950526014 Robert Granetz Shot 14 -- Plasma, disrupted at 0.42 s. VDE. No hard x-rays.

Next shot: raise ZCUR by 5 mm. Methane puff enabled.

May 26 1995 12:10:40:300PM 950526015 Robert Granetz Shot 15 -- Plasma, disrupted at 0.41 s. TF and PF crowbarred. Vinnie thinks
the OH2L had a fault which caused the disruption.

Next shot: repeat with no changes.

May 26 1995 12:47:34:390PM 950526016 Robert Granetz Shot 16 -- Fizzle.

Next shot: repeat with no changes.

May 26 1995 12:48:29:040PM 950526017 Robert Granetz Shot 17 -- Plasma, good shot. Upper x-pt. No methane.

Next shot: enable NINJA methane puff.

May 26 1995 01:01:16:750PM 950526018 Robert Granetz Shot 18 -- Plasma, disrupted at 0.99 s, VDE. Good plume data. The plume
reversed direction.

Next shot: another NINJA methane puff, with different filter.

May 26 1995 01:09:54:210PM 950526019 Robert Granetz Shot 19 -- Plasma, good shot. Good plume data.

Next shot: raise density to nl_04=1.2e20 m-2, with methane puff.

May 26 1995 01:29:59:980PM 950526020 Robert Granetz Shot 20 -- Plasma, disrupted at 0.40, which is before I made any change in
the density programming. VDE.

Next shot: repeat with no changes.

May 26 1995 01:45:27:580PM 950526021 Robert Granetz Shot 21 -- Plasma, good shot. Good plume data. Density made it to 1.2e20 m-2.

Next shot: repeat with different filter.

May 26 1995 01:55:08:560PM 950526022 Robert Granetz Shot 22 -- Plasma, good shot. Good plume data, good probe data.

Next shot: repeat with no methane, to get a background shot.

May 26 1995 02:07:41:240PM 950526023 Robert Granetz Shot 23 -- Plasma, good shot. Good baseline shot.

Next shot: NINJA methane puff from bottom divertor.

May 26 1995 02:17:31:580PM 950526024 Robert Granetz Shot 24 -- Runaway screamer.

Next shot: raise pre-fill from 2.0 to 2.2e-5 torr.

May 26 1995 02:29:00:250PM 950526025 Robert Granetz Shot 25 -- Plasma, good shot.

Next shot: raise density to nl_04=1.6e20 m-2.

May 26 1995 02:42:49:610PM 950526026 Robert Granetz Shot 26 -- Plasma, good shot. Density made it to 1.6e20 m-2. Good plume data,
Good FSP data.

Next shot: repeat with NINJA methane puff and different filter.

May 26 1995 02:56:52:010PM 950526027 Robert Granetz Shot 27 -- Plasma, disrupted at 0.83 s. VDE. Probably due to molybdenum
injection. Got plume data.

Next shot: reduce density to nl_04=1.2e20 m-2 and puff from the
bridge of the divertor. Still upper x-pt configuration.

May 26 1995 03:04:17:250PM 950526028 Robert Granetz Shot 28 -- Fizzle.

Next shot: repeat with no changes.

May 26 1995 03:16:05:360PM 950526029 Robert Granetz Shot 29 -- Plasma, good shot. Good plume data and FSP data. Nl_04=1.2e20 m-2.
This is the last upper x-pt configuration in this series.

Next shot: change to limiter plasma configuration, with
nl_04=1.0e20 m-2.

May 26 1995 03:33:14:850PM 950526030 Robert Granetz Shot 30 -- Plasma, limited, disrupted at 0.85 s, maybe due to more carbon
getting in.

Next shot: repeat with different filter.

May 26 1995 03:42:17:140PM 950526031 Robert Granetz Shot 31 -- Plasma, good shot. Good data. Carbon brightness is a factor of
4 to 5 higher than diverted plasmas.

Next shot: raise density to nl_04=1.5e20 m-2. Continue methane
puffing from inboard midplane.

May 26 1995 03:54:45:940PM 950526032 Robert Granetz Shot 32 -- Plasma, disrupted at about 0.45 s. Looks like it got very dirty
and resistive.

Next shot: reduce density back to nl_04=1.0e20 m-2, turn off
NINJA, but puff methane through B-side-lower. (B-side-lower plenum
pressure is 3.4 psi)

May 26 1995 04:04:18:490PM 950526033 Robert Granetz Shot 33 -- Plasma, good shot. Limited, with methane puff from B-side-lower
valve. This is the shot I need for screening comparison on non-
recycling impurities. nl_04=1.1e20 m-2.

Next shot: switch back to lower x-pt, with methane puff from
B-side-lower valve.

May 26 1995 04:09:03:050PM 950526034 Robert Granetz Shot 34 -- Plasma, disrupted at 0.23 s, prior to becoming diverted. Disruption
was caused by an OH2L fault.

Next shot: repeat with no changes.

May 26 1995 04:31:05:100PM 950526035 Robert Granetz Shot 35 -- Plasma, good shot. Diverted, lower x-pt, with methane puff from
B-side-lower valve. This is the other shot I need for screening
comparison of non-recycling impurity. nl_04=1.1e20 m-2.

Next shot: repeat with NINJA puffing of methane from the private
flux zone. B-side-valve is disabled.

May 26 1995 05:27:30:320PM 950526035 Robert Granetz Comparison of CII signal shows a factor of two difference between the limiter
plasma (033) and the diverted plasma (035). The CII signal is a measure of
carbon flux through the edge. Measurements of CVI brightness taken
by the McPherson show a factor of 2-3 difference.

May 26 1995 04:35:39:050PM 950526036 Robert Granetz Shot 36 -- Plasma, good shot. Lower x-pt, with methane puff from private
flux zone.

Next shot: repeat, but with no methane puffing, to get a baseline.

May 26 1995 04:45:21:180PM 950526037 Robert Granetz Shot 37 -- Plasma, good shot. No methane puffing. Good baseline shot for
diverted, lower x-pt. nl_04=1.1e20 m-2.

Next shot: switch to limiter configuration again, but without
any methane puffing, to get a baseline shot at nl_04=1.0e20 m-2.

May 26 1995 05:15:22:300PM 950526038 Robert Granetz Shot 38 -- Plasma, good shot. No methane puffing. Good baseline shot for
limiter configuration. nl_04=1.1e20, with some wobbles. Brian
got some fast scanning probe data.

May 26 1995 05:15:38:210PM 950526038 Robert Granetz Using these two baseline shots (037 and 038) with the two methane shots (033
and 035), Jim Terry reports a factor of two difference in CVI brightness.

Engineering Operator Comments

Shot Time Type Status Comment

1 08:35:16:400AM Plasma Ok

2 08:51:58:830AM Plasma Ok

3 09:07:25:090AM Plasma Ok

4 09:23:33:930AM Plasma Ok

5 09:37:10:750AM Plasma Ok

6 09:51:30:660AM Plasma Ok

7 10:06:35:220AM Plasma Ok

8 10:20:33:300AM Plasma Ok

9 10:34:35:380AM Plasma Ok

10 10:48:32:930AM Plasma Ok

11 11:01:28:480AM Plasma Ok

12 11:13:17:840AM Plasma Ok

13 11:29:22:270AM Plasma Ok

14 11:45:00:600AM Plasma Ok

15 12:00:48:140PM Plasma Bad oh2l comm fault

16 12:31:41:170PM Plasma Ok

17 12:41:37:860PM Plasma Ok

18 12:53:39:100PM Plasma Ok Comm fault OH2U OH1

19 01:05:59:020PM Plasma Ok

20 01:17:58:500PM Plasma Ok

21 01:30:35:000PM Plasma Ok

22 01:49:07:340PM Plasma Ok

23 02:03:18:430PM Plasma Ok

24 02:14:40:420PM Plasma Ok

25 02:24:27:020PM Plasma Ok

26 02:35:21:150PM Plasma Ok

27 02:46:53:380PM Plasma Ok

28 03:00:11:640PM Plasma Ok

29 03:09:47:930PM Plasma Ok

30 03:20:38:320PM Plasma Ok

31 03:32:18:640PM Plasma Ok

32 03:42:31:610PM Plasma Ok

33 03:54:52:900PM Plasma Ok

34 04:04:34:530PM Plasma Bad Comm fault OH2L caused disruption.

35 04:16:29:620PM Plasma Ok

36 04:27:51:450PM Plasma Ok

37 04:40:34:020PM Plasma Ok

38 04:51:52:330PM Plasma Ok

Session Leader Comments
May 26 1995 08:43:49:090AM		Gary McCracken	Study of plasma flows using gas injection plumes (MP 104) The plan is to generally repeat the program of CH4 injection obtained on run 950414 but this time with grad B drift down. The CH4 will be injected principally from the NINJA system at the inner wall midplane and observed with the CCD cameras using CII CII filters. We will compare the X-point at the top and at the bottom. We will also look at the effect of injecting into limiter discharges. We plan to use these shots to measure carbon screening and to use B-side lower injection as well as different NINJA positions
May 26 1995 05:33:11:530PM		Gary McCracken	Brief summary: Good day; We did a density scan with a lower x-point plasma from nl04=0.8 to 1.8e20 with methane injection through the inner wall capillary (B16-001) CII and CI plumes were observed always going towards the divertor target. This is different to the results from the run950414 with the grad B drift upwards, where we got the flow reversing at high density We then did upper X-point discharges.We again got a density scan and the flow was always towards the upper divertor We also did some puffing through the lower divertor capillaries B26-019 and B22-022 with upper X-point. Interestingly we saw clear toroidal flow viewing from the B-top camera. No apprecaible signal was observed from the B26-019 cap when the X-point was down
May 26 1995 08:49:04:090AM	950526001	Gary McCracken	shot 001 Good shot. nlo40.8e20. Inside and outside gaps good. Plasma position for FSP very good. Plan to inject CH4 through NINJA valves B16-001 and B22-022 next shot
May 26 1995 09:05:31:040AM	950526002	Gary McCracken	shot 002 Inject CH4 through NINJA valves B16-001 and B22-022 CII filter Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms Good shot; CH4 injected and observed both on B-side camera and on A-side (unfiltered) camera. It is clearly seen from both valves and is quite bright. Outer strike point at FMP probe 4
May 26 1995 09:18:30:810AM	950526003	Gary McCracken	shot 003 Inject CH4 through NINJA valves B16-001 only CIII filter Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms Good shot; CH4 injected and observed on B-side camera . Intensity looks better than previously observed with the CIII filter. The plasma is clearly being fuelled by the NINJA system and the density is going up beyond the value demanded nl04=1e20
May 26 1995 09:32:26:280AM	950526004	Gary McCracken	shot 004 Inject CH4 through NINJA valves B16-001 and B22-022 CII filter Plenum pressure 6.2 psi. Trigger at 450 ms for 300 ms Disruption at 0.6 s CH4 observed on B-side camera for 2 or 3 frames. Asked for nlo4=1.3e20 reached 1.15e20 before disruption. We will have a background shot without any CH4 next shot
May 26 1995 09:49:33:830AM	950526005	Gary McCracken	shot 005 NO CH4 injected. Good shot Asked for nlo4=1.3e20 and got it. We will go back to gas puffing next shot
May 26 1995 10:06:37:560AM	950526006	Gary McCracken	shot 006 CH4 injected.B16-001 only, conditions as before, CIII filter Good shot. Clear plume. nl04=1.38e20 nice and constant It is clear in both this shot and 005 that we are getting detachment at 0.53 s, up to probe 5. shot 005 was without methane. The strike point is on probe 3 to 4, moving up towards the end of the shot
May 26 1995 10:18:57:580AM	950526006	Gary McCracken	shot 006 CORRECTION :USED CII FILTER THIS SHOT NOT CIII AS PREVIOUSLY STATED
May 26 1995 10:17:25:430AM	950526007	Gary McCracken	shot 007 CH4 injected.B16-001 only, conditions as before, CIII filter Plume observed but much weaker. nl04=1.4e20
May 26 1995 10:32:17:050AM	950526008	Gary McCracken	shot 008 Increased demand density to 1.6e20. No methane injected to obtain background at higher density. Good shot; nl04 =1.64e20
May 26 1995 10:45:52:000AM	950526009	Gary McCracken	shot 009 CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s). B16-001 valve only ;plenum pressure still 6.15 psi Good shot; CIII plume clearly towards the divertor still, though faint. No sign of reversing direction at high density as seen on 950414 run nl04 =1.69e20
May 26 1995 10:56:49:130AM	950526010	Gary McCracken	shot 010 CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s). B16-001 valve only ;plenum pressure still 6.15 psi CII filter (last shot CIII filter) Good shot; CII plume still downwards ;bright but possibly decaying faster along the field line. nl04=1.65e20
May 26 1995 11:15:39:060AM	950526011	Gary McCracken	shot 011 Density demand raised to 1.8e20 CH4 injected at about 0.7 s (trigger at 0.55s for 0.3 s). B16-001 valve only ;plenum pressure 6.15 psi CII filter Good shot until 0.85 s then disrupted CII plume still downwards, looks fine nl04=1.76e20 at disruption, still rising
May 26 1995 11:53:53:090AM	950526013	Gary McCracken	shot 013 No methane injection; nl04 0.8e20 Disrupted 0.95 s
May 26 1995 11:49:35:760AM	950526014	Gary McCracken	shot 012 Change to upper X-point Reduce density to 0.8e20, no methane puff. Disrupted at 0.4 s; not clear why.
May 26 1995 11:59:20:620AM	950526014	Gary McCracken	shot 014 Methane injection B16-001 valve, timing and pressure as above Tried to improve plasma elongation and position for FSP Disrupted 0.45 s; nl04 =0.6e20 at disruption. Gas in after disruption but bright spots at capillaries one frame before disruption. No obvious explanation.
May 26 1995 12:35:07:880PM	950526015	Gary McCracken	shot 015 No methane injection Raised plasma and reduced elongation Early disruption 0.4 s.
May 26 1995 12:35:35:170PM	950526015	Gary McCracken	shot 016 No methane injection Fizzle
May 26 1995 12:52:30:260PM	950526016	Gary McCracken	shot 016 No methane injection Fizzle
May 26 1995 12:54:41:140PM	950526017	Gary McCracken	shot 017 No methane injection ;Background shot Good plasma with upper X-point nl04 =0.84e20
May 26 1995 01:02:15:460PM	950526018	Gary McCracken	shot 018 Methane injection , CII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure still 6.15 psi Good plasma with upper X-point nl04 =0.84e20. CII plume clearly visible with reversed direction, as expected.
May 26 1995 01:17:46:910PM	950526019	Gary McCracken	shot 019 Methane injection , CIII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure still 6.15 psi Good shot; Clear CIII plume towards upper divertor, although faint. It is however more symmetric than the CII plume Clear step up on CII signal on C-port at 0.68 s, on this and previous pulse, compared with shot 17 which had no methane injected
May 26 1995 01:24:21:800PM	950526020	Gary McCracken	shot 020 Methane injection , CIII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi Disrupted at 0.4 s
May 26 1995 01:36:38:060PM	950526021	Gary McCracken	shot 021 Try repeat of shot 20 Methane injection , CIII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi Did not fire
May 26 1995 01:45:58:110PM	950526021	Gary McCracken	shot 021 Try again repeat of shot 20 Methane injection , CIII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi Good shot; clear but faint CIII plume towards upper divertor Note plume reverses around the time of current ramp down.
May 26 1995 01:54:14:800PM	950526022	Gary McCracken	shot 022 Repeat shot Methane injection , CII filter; B16-001 only; Trigger at 0.55 s for 0.3 s; Plenum pressure 6.2 psi Good shot; clear CII plume towards upper divertor Plume again reverses around the time of current ramp down.
May 26 1995 02:10:08:740PM	950526023	Gary McCracken	shot 023 Repeat shot No methane injection, background shot Good shot nl04= 1.22e20. Very nice flat CII signal from C-port
May 26 1995 02:22:29:490PM	950526024	Gary McCracken	shot 024 Methane injection, B26-019 at lower divertor; Trigger at 0.55s for 0.3 s ; 6.1 psi Disruption at 0.4 s Not clear why t
May 26 1995 02:39:30:680PM	950526025	Gary McCracken	shot 025 Methane injection, B26-019 at lower divertor; CII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Good shot nl04 1.29 ; CII plume; Faint, but toroidal flow observed on the B-top camera looking at B26-019
May 26 1995 02:45:13:220PM	950526026	Gary McCracken	shot 026 Methane injection, B16-001 at inner wall; CII filter, higher density Trigger at 0.55s for 0.3 s ; 6.1 psi Good shot ; nl04 1.29 ; CII plume;
May 26 1995 02:53:13:260PM	950526027	Gary McCracken	shot 027 Methane injection, B16-001 at inner wall; CIII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Disruption at 0.82 s,but got the CIII plume, faint but clearly towards the upper divertor ; nl04 1.62
May 26 1995 02:55:23:880PM	950526027	Gary McCracken	shot 027 Methane injection, B16-001 at inner wall; CIII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Disruption at 0.82 s,but got the CIII plume, faint but clearly towards the upper divertor ; nl04=1.62
May 26 1995 03:03:33:970PM	950526028	Gary McCracken	shot 028 Methane injection, B22-022 at inner upper divertor with X-point at top to compare with shot 25 ,(puff from B26-019); CII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Fizzle
May 26 1995 03:20:46:040PM	950526029	Gary McCracken	shot 029 Methane injection, B22-022 at inner upper divertor with X-point at top to compare with shot 25 ,(puff from B26-019); CII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Very clear flow along the field observed in the B-top camera Good FSP data obtained. This should allow us to compare the flow derived from the plume with that derived from the scanning probe.
May 26 1995 03:29:55:710PM	950526030	Gary McCracken	shot 030 Changed to limited plasma Methane injection, B16-001 at inner wall ; CII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Disrupted at 0.85 s, but can see the CII at the midplane. Very localized symmetric spot, presumably because the ionization is so fast when it enters in the core plasma
May 26 1995 03:43:34:840PM	950526031	Gary McCracken	shot 031 Limited plasma Methane injection, B16-001 at inner wall ; CIII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Good shot ; CIII bright light spreads uniformly in both directions
May 26 1995 03:52:32:370PM	950526032	Gary McCracken	shot 032 Limited plasma Methane injection, B16-001 at inner wall ; CIII filter Trigger at 0.55s for 0.3 s ; 6.1 psi Repeat shot except higher density Disrupted at 0.45 s due to plasma being too resistive. Why?
May 26 1995 04:09:15:280PM	950526033	Gary McCracken	shot 033 Limited plasma Methane injection, through B-side lower; 0.6 to 0.95 s; Plenum pressure 3.4 psi. CIII filter Good shot . Clear signal on CII at C-port
May 26 1995 04:10:13:950PM	950526033	Gary McCracken	shot 033 Limited plasma Methane injection, through B-side lower; 0.6 to 0.95 s; Plenum pressure 3.4 psi. CIII filter Good shot . Clear signal on CII at C-port
May 26 1995 04:14:46:450PM	950526034	Gary McCracken	shot 034 Lower X-point to compare with previous limited plasma Methane injection, through B-side lower; 0.6 to 0.95 s; Plenum pressure 3.4 psi. CIII filter Died early; Power supply problem on lower OH2
May 26 1995 04:27:22:960PM	950526035	Gary McCracken	shot 035 Lower X-point to compare with previous limited plasma Methane injection, through B-side lower; 0.6 to 0.95 s; Plenum pressure 3.4 psi. CIII filter Good shot clear signal on Cii at C-port. the delta CIi is about half of the value in the limiter shot
May 26 1995 04:45:04:930PM	950526036	Gary McCracken	shot 036 Lower X-point Methane injection, through B26-019; Trigger at 0.55 s for 0.3 s; Plenum pressure 6.0 psi. CII filters Good shot ; nl04 =1.1e20 Very faint signal on the B-top camera but not certain it comes from the gas puffing at the PFZ
May 26 1995 04:51:21:970PM	950526037	Gary McCracken	shot 037 Lower X-point No Methane injection, Backgroundshot for spectroscopy Good shot; nl04=1.08e20. Nice low flat CII background signal
May 26 1995 05:12:23:790PM	950526038	Gary McCracken	shot 038 Limiter shot; Another background shot for spectroscopy No Methane injection, Good shot; nl04=1.15e20.

Physics Operator Comments
May 25 1995 06:27:03:800PM		Robert Granetz	MP #104, Investigation of Plasma Flows Using Gas Injection Plumes Primary purpose: Inject CH4 and He at the inner wall and divertor with NINJA system and study plumes in plasmas with B x grad B drift down. Compare to data from 950414, when the B x grad B drift was reversed. We will run lower x-pt's, upper x-pt's, and limited plasmas, at several densities and several puffing locations. Secondary purpose: Compare limiter/divertor screening of methane, which is a non-recycling impurity
May 25 1995 06:27:33:940PM		Robert Granetz	Setup: Lower x-pt: 950512027, with density changed to nl_04=0.8e20 m-2, Upper x-pt: 950322029, with density changed to nl_04=0.8e20 m-2, Limited : 950519021, with density changed to nl_04=1.0e20 m-2. To speed up PCS operations, I setup a PCS the evening before this run with segments 2,3, & 4 loaded with the three configurations, respectively. Engineering preparations: Setup up from shot 950512027 (including commutation resistors, TF start time, TF current, etc). Normal ECDC in D2. Set pre-fill at 1.8e-5 torr of D2. Fill A-side with D2 at 19-20 psi. Fill B-side-lower with methane at 3 psi, BUT LEAVE DISABLED! Fill the NINJA plenum with methane at 5 psi. All other gas valves should be disabled as well.
May 26 1995 08:56:56:830AM	950526001	Robert Granetz	Shot 01 -- Setup for a lower x-pt baseline shot. No methane puffing. Plasma, good shot. Density oscillated a bit. Next shot: repeat with NINJA system puffing methane from the inboard midplane location and from the inner divertor nose location.
May 26 1995 09:05:09:530AM	950526002	Robert Granetz	Shot 02 -- Plasma, good shot. Methane plumes were seen. On request from Brian, we will tweak upper and lower x-pt positions on the next shot. Next shot: tweak upper and lower x-pt locations, and puff methane from midplane only.
May 26 1995 09:20:49:140AM	950526003	Robert Granetz	Shot 03 -- Plasma, good shot. Good plume (CIII). Next shot: tweak upper x-pt another 5 mm up. NINJA puff from both locations enabled.
May 26 1995 09:34:35:090AM	950526004	Robert Granetz	Shot 04 -- Plasma, disrupted at 0.59 s. VDE. Probably not due to excessive radiation. Elongation was very high. Next shot: lower ZCUR by 5 mm, and turn off methane in order to get a background shot.
May 26 1995 09:50:45:090AM	950526005	Robert Granetz	Shot 05 -- Plasma, good shot. Density got to the requested value of 1.3e20 m-2. Zxray did move down. Next shot: NINJA methane puff from midplane.
May 26 1995 10:03:08:730AM	950526006	Robert Granetz	Shot 06 -- Plasma, good shot. Good plume data (CIII). Jim Terry reports that carbon background level is gradually rising from shot to shot. Next shot: NINJA methane puff from midplane, different filter.
May 26 1995 10:03:28:250AM	950526006	Robert Granetz	Engineering has enabled the I^2*t circuit starting with the next shot.
May 26 1995 10:14:06:780AM	950526007	Robert Granetz	Shot 07 -- Plasma, good shot. Good plume data (CIII). Next shot: increase density to nl_04=1.6e20 m-2. Turn off methane.
May 26 1995 10:30:10:470AM	950526008	Robert Granetz	Shot 08 -- Plasma, good shot. Density got to nl_04=1.6e20 m-2 by 0.75 s. Next shot: enable NINJA methane puff.
May 26 1995 10:46:05:040AM	950526009	Robert Granetz	Shot 09 -- Plasma, good shot. Got plume data (CIII). Next shot: NINJA methane puff with different filter.
May 26 1995 10:51:51:760AM	950526010	Robert Granetz	Shot 10 -- Plasma, good shot. Good plume data (CII). Next shot: raise density to nl_04=1.8e20 m-2. Also puff methane.
May 26 1995 11:08:27:120AM	950526011	Robert Granetz	Shot 11 -- Plasma, disrupted at 0.86 s. Got good plume data anyway. Next shot: change to upper x-pt at nl_04=0.8e20 m-2. No methane puffing.
May 26 1995 11:27:19:930AM	950526012	Robert Granetz	Shot 12 -- Plasma, disrupted at 0.41 s. VDE. Next shot: slow down the current rise with a little tweak.
May 26 1995 11:44:41:820AM	950526013	Robert Granetz	Shot 13 -- Plasma, disrupted at 0.96 s. VDE. Some hard x-rays. Brian wants the plasma lowered by 1 cm so the scanning probe can reach, but we're near the vertical stability limit. Next shot: Turn on EF2_BY_EF4 control, lower ZCUR and ZXU by 1 cm, increase RCUR by 2 mm, and raise pre-fill from 1.8 to 2.0e-5 torr. Also turn on methane puff.
May 26 1995 11:58:42:710AM	950526014	Robert Granetz	Shot 14 -- Plasma, disrupted at 0.42 s. VDE. No hard x-rays. Next shot: raise ZCUR by 5 mm. Methane puff enabled.
May 26 1995 12:10:40:300PM	950526015	Robert Granetz	Shot 15 -- Plasma, disrupted at 0.41 s. TF and PF crowbarred. Vinnie thinks the OH2L had a fault which caused the disruption. Next shot: repeat with no changes.
May 26 1995 12:47:34:390PM	950526016	Robert Granetz	Shot 16 -- Fizzle. Next shot: repeat with no changes.
May 26 1995 12:48:29:040PM	950526017	Robert Granetz	Shot 17 -- Plasma, good shot. Upper x-pt. No methane. Next shot: enable NINJA methane puff.
May 26 1995 01:01:16:750PM	950526018	Robert Granetz	Shot 18 -- Plasma, disrupted at 0.99 s, VDE. Good plume data. The plume reversed direction. Next shot: another NINJA methane puff, with different filter.
May 26 1995 01:09:54:210PM	950526019	Robert Granetz	Shot 19 -- Plasma, good shot. Good plume data. Next shot: raise density to nl_04=1.2e20 m-2, with methane puff.
May 26 1995 01:29:59:980PM	950526020	Robert Granetz	Shot 20 -- Plasma, disrupted at 0.40, which is before I made any change in the density programming. VDE. Next shot: repeat with no changes.
May 26 1995 01:45:27:580PM	950526021	Robert Granetz	Shot 21 -- Plasma, good shot. Good plume data. Density made it to 1.2e20 m-2. Next shot: repeat with different filter.
May 26 1995 01:55:08:560PM	950526022	Robert Granetz	Shot 22 -- Plasma, good shot. Good plume data, good probe data. Next shot: repeat with no methane, to get a background shot.
May 26 1995 02:07:41:240PM	950526023	Robert Granetz	Shot 23 -- Plasma, good shot. Good baseline shot. Next shot: NINJA methane puff from bottom divertor.
May 26 1995 02:17:31:580PM	950526024	Robert Granetz	Shot 24 -- Runaway screamer. Next shot: raise pre-fill from 2.0 to 2.2e-5 torr.
May 26 1995 02:29:00:250PM	950526025	Robert Granetz	Shot 25 -- Plasma, good shot. Next shot: raise density to nl_04=1.6e20 m-2.
May 26 1995 02:42:49:610PM	950526026	Robert Granetz	Shot 26 -- Plasma, good shot. Density made it to 1.6e20 m-2. Good plume data, Good FSP data. Next shot: repeat with NINJA methane puff and different filter.
May 26 1995 02:56:52:010PM	950526027	Robert Granetz	Shot 27 -- Plasma, disrupted at 0.83 s. VDE. Probably due to molybdenum injection. Got plume data. Next shot: reduce density to nl_04=1.2e20 m-2 and puff from the bridge of the divertor. Still upper x-pt configuration.
May 26 1995 03:04:17:250PM	950526028	Robert Granetz	Shot 28 -- Fizzle. Next shot: repeat with no changes.
May 26 1995 03:16:05:360PM	950526029	Robert Granetz	Shot 29 -- Plasma, good shot. Good plume data and FSP data. Nl_04=1.2e20 m-2. This is the last upper x-pt configuration in this series. Next shot: change to limiter plasma configuration, with nl_04=1.0e20 m-2.
May 26 1995 03:33:14:850PM	950526030	Robert Granetz	Shot 30 -- Plasma, limited, disrupted at 0.85 s, maybe due to more carbon getting in. Next shot: repeat with different filter.
May 26 1995 03:42:17:140PM	950526031	Robert Granetz	Shot 31 -- Plasma, good shot. Good data. Carbon brightness is a factor of 4 to 5 higher than diverted plasmas. Next shot: raise density to nl_04=1.5e20 m-2. Continue methane puffing from inboard midplane.
May 26 1995 03:54:45:940PM	950526032	Robert Granetz	Shot 32 -- Plasma, disrupted at about 0.45 s. Looks like it got very dirty and resistive. Next shot: reduce density back to nl_04=1.0e20 m-2, turn off NINJA, but puff methane through B-side-lower. (B-side-lower plenum pressure is 3.4 psi)
May 26 1995 04:04:18:490PM	950526033	Robert Granetz	Shot 33 -- Plasma, good shot. Limited, with methane puff from B-side-lower valve. This is the shot I need for screening comparison on non- recycling impurities. nl_04=1.1e20 m-2. Next shot: switch back to lower x-pt, with methane puff from B-side-lower valve.
May 26 1995 04:09:03:050PM	950526034	Robert Granetz	Shot 34 -- Plasma, disrupted at 0.23 s, prior to becoming diverted. Disruption was caused by an OH2L fault. Next shot: repeat with no changes.
May 26 1995 04:31:05:100PM	950526035	Robert Granetz	Shot 35 -- Plasma, good shot. Diverted, lower x-pt, with methane puff from B-side-lower valve. This is the other shot I need for screening comparison of non-recycling impurity. nl_04=1.1e20 m-2. Next shot: repeat with NINJA puffing of methane from the private flux zone. B-side-valve is disabled.
May 26 1995 05:27:30:320PM	950526035	Robert Granetz	Comparison of CII signal shows a factor of two difference between the limiter plasma (033) and the diverted plasma (035). The CII signal is a measure of carbon flux through the edge. Measurements of CVI brightness taken by the McPherson show a factor of 2-3 difference.
May 26 1995 04:35:39:050PM	950526036	Robert Granetz	Shot 36 -- Plasma, good shot. Lower x-pt, with methane puff from private flux zone. Next shot: repeat, but with no methane puffing, to get a baseline.
May 26 1995 04:45:21:180PM	950526037	Robert Granetz	Shot 37 -- Plasma, good shot. No methane puffing. Good baseline shot for diverted, lower x-pt. nl_04=1.1e20 m-2. Next shot: switch to limiter configuration again, but without any methane puffing, to get a baseline shot at nl_04=1.0e20 m-2.
May 26 1995 05:15:22:300PM	950526038	Robert Granetz	Shot 38 -- Plasma, good shot. No methane puffing. Good baseline shot for limiter configuration. nl_04=1.1e20, with some wobbles. Brian got some fast scanning probe data.
May 26 1995 05:15:38:210PM	950526038	Robert Granetz	Using these two baseline shots (037 and 038) with the two methane shots (033 and 035), Jim Terry reports a factor of two difference in CVI brightness.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:35:16:400AM	Plasma	Ok
2	08:51:58:830AM	Plasma	Ok
3	09:07:25:090AM	Plasma	Ok
4	09:23:33:930AM	Plasma	Ok
5	09:37:10:750AM	Plasma	Ok
6	09:51:30:660AM	Plasma	Ok
7	10:06:35:220AM	Plasma	Ok
8	10:20:33:300AM	Plasma	Ok
9	10:34:35:380AM	Plasma	Ok
10	10:48:32:930AM	Plasma	Ok
11	11:01:28:480AM	Plasma	Ok
12	11:13:17:840AM	Plasma	Ok
13	11:29:22:270AM	Plasma	Ok
14	11:45:00:600AM	Plasma	Ok
15	12:00:48:140PM	Plasma	Bad	oh2l comm fault
16	12:31:41:170PM	Plasma	Ok
17	12:41:37:860PM	Plasma	Ok
18	12:53:39:100PM	Plasma	Ok	Comm fault OH2U OH1
19	01:05:59:020PM	Plasma	Ok
20	01:17:58:500PM	Plasma	Ok
21	01:30:35:000PM	Plasma	Ok
22	01:49:07:340PM	Plasma	Ok
23	02:03:18:430PM	Plasma	Ok
24	02:14:40:420PM	Plasma	Ok
25	02:24:27:020PM	Plasma	Ok
26	02:35:21:150PM	Plasma	Ok
27	02:46:53:380PM	Plasma	Ok
28	03:00:11:640PM	Plasma	Ok
29	03:09:47:930PM	Plasma	Ok
30	03:20:38:320PM	Plasma	Ok
31	03:32:18:640PM	Plasma	Ok
32	03:42:31:610PM	Plasma	Ok
33	03:54:52:900PM	Plasma	Ok
34	04:04:34:530PM	Plasma	Bad	Comm fault OH2L caused disruption.
35	04:16:29:620PM	Plasma	Ok
36	04:27:51:450PM	Plasma	Ok
37	04:40:34:020PM	Plasma	Ok
38	04:51:52:330PM	Plasma	Ok