Alcator C-Mod Run 950202 Information

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Miniproposals
Miniproposal:039
Date Filed: 3/10/1994
Title:Effect of divertor geometry on detachment
First Author:Bruce Lipschultz
Session Leader:Bruce Lipschultz (shots 1-36)

Operators
Session leader(s):Bruce Lipschultz
Physics operator(s):John Goetz
Engineering operator(s):Frank Silva,Vinny Bertolino

Engineering Operator Run Comment
silva/bertolino

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:12:163PM
Author: To Be Determined
run 950202

Engineering operator: F. Silva
Physics operator J. Goetz
Session leader BLip

This run was a continuation of mini-proposals 39
('effect of geometry on divertor detachment') with a sidetrack
to delve into some details of mp #81 - 'effect of strike point position
on the extent of detachment'.
The run was very successful. We were able to make small changes in
nebar and see the corresponding changes in the extent of detachment. This
was done at both 800 kA and 500 kA. We also switched to flat-plate divertor
geometry late inthe run and using the same density steps explored
detachment and it;'s extent there.
Operationally, we found that to better trust the probe output it
was useful to sweep the strike point around some nominal position for a
fixed density. This proved very useful.
There is a fairly narrow density range
from the onset of detachment until the detachment reaches the nose of the
outer divertor. At 800kA this window is between nl04=1. and 1.5 e20. We did
not push above that density to see what it took to detach probe 8 in all cases.
The comparison of flat-plate and inclined-plate divertor continues.
At 500 kA the detachment threshold for the inclined and flat-plate geometries
were nl04=0.5 and 0.9e20 respectively, so higher for flat-plate. This is
similar to the 800kA results of Tuesday and the previous flat-plate run where the
inclined plate/slot had a threshold of nl04=1.0e20 and the flat-plate at
nl04~1.8e20.

The shot description follows:

shot 1: one power supply not taken off of PLC control.

shot 2: Fine shot at nl04= 0.7e20. Probe will fire the next shot.

shot 4: Shot is fine but apparently the edge::probe tree was not turned
back on. We will wait for the dust to settle here and run this shot again!!!

shot 5: shot fine except for Moly peak early in time. We are
still having probe problems. One more time with feeling.

shot 6: probe went in fine, nl04=0.7. Next shot nl04=0.9

shot 7: fine shot at nl04=0.9e20. probe scan fine as well. next
shot at nl04=1.1e20.

shot 8: very strange shot. The footprint of Isat on the outer divertor
shows a major change at ~.85 sec. There appears to be a MARFE during most
of the shot that doesn't slip into the divertor until then. The MARFE
apparently causes most of the divertor to apper to be detached.

shot 9: The shot went fine but no data because the
camac did not initialize. TWF has fixed this problem and we will
redo the shot.

shot 10: Finally we got the nl04=1.1e20. Probe went in fine and we will
raise the density for the next shot. Looks like the peak pressure has
moved to probe 4 so detachment at least on probes 2 & 3.

shot 11: Finally we got the nl04=1.3e20. Detachment even further up the
plate to somewhere around probe 6-7. Probe went in fine and we will
raise the density for the next shot.

shot 12: fizzle, gas too high

shot 13: nl04=1.5e20. possibly some detachment on probe 8.

shot 14: We decided to sweep the strike point. This went fine.
nl04=1.1e20. Peak in pressure profile moves up and down the plate.
next shot same sweep but nl04=1.3e20.

shot 15: sweep of strike point with nl04=1.3e20. next shot sweep a little
further (to probe 5) and back to nl04=1.1e20.

shot 16: Very nice sweep with nl04=1.1e20. We see the peak in Isat move
up to probe 5.

shot 17: 500 kA, nl04=1.1e20. This shot has detachment all the way up
the inclined plate through probe 8.

shot 18: nl04=0.9e20, swept strike point. Detachment through probe 7.
lower the density more on the next shot.

shot 19: nl04=0.7e20. This shot is probably not useful. The outer gap is
too small (5mm) and there is an event at .82 sec which changes the
profile in the divertor. We will repeat this shot.


shot 20: Better but outer gap too small still. We will repeat once
again - nl04=0.7e20.

shot 21: still settling the gap. Also it appears that the Ar level in
the machine is too high - possible inner seal leak. We will repeat
this shot once again without Ar and hopefully better gap control.
Still at nl04=0.7e20.

shot 22: This shot looks pretty good at nl04=0.7e20. We will lower the
density on the next shot. Ar off for this one and next. Detachment midway
upthe divertor plate.

shot 23: No detachment at nl04=0.5e20. Gaps are good and we will keep
the Ar off until the end of this density scan. Next shot nl04=0.6e20.

shot 24: nl04=0.6e20 to try to zero in on threshold better.There appears
to be a slight amount of detachment on this shot. Back to repeat
nl04=1.1e20 without Ar next shot.

shot 25: detached up through probe 7. nl04=1.1e20.

shot 26: nl04=0.9e20, detachment up through probe 7. next shot on to
slot divertor.

shot 27: tried to switch to slot w/ne04=1.1e20. However we don't
seem to have moved the separatrix far enough. Detached up
through probe 7. One more try for slot.

shot 28: still didn't achieve 'slotness'. nl04=0.9e20. Strike point on
probe 1 the whole shot. Next shot on to flat-plate.

shot 29: flat-plate started ok but EF1 gave out so the plasma disrupted
at .67 sec. Try again with probe as well.

shot 30: We appeared to get the required sweep. However, the scanning
probe is not able to reach this plasma at all times. nl04=0.9e20.
We will try to hold the separatrix position more constant for the
probe and repeatthe shot. There does not appear to be any detachment.

shot 31: Flat-plate again ok at nl04=0.9e20. Injection at 0.85 sec which
interrupts the probe scan. We will repeat and try to get the position
of the plasma and probe more appropriate.

shot 32: nl04=0.9e20, no injections. Probe went in and got 2 good
scans. We will now go to higher density.

shot 33: Very nice sweep. nl04=1.1e20. Looks like detachment on
probe 8. However the probe was not properly enabled that shot - no FSP.

shot 34: nl04 = 1.1e20, detachment and FSP made scan. We will go to
lower density next shot to make sure we have the detachment
threshold correct.

shot 35: nl04=0.7e20, no detachment obvious. FSP scan went all right.
However, the signals on probe 8 appear a little awry. We will repeat
with slightly higher density.

shot 36: good profile at probe 8 during sweep for nl04=0.8e20.



Physics Operator Summaries
Entered: Jul 7 2004 04:36:53:083PM
Author: To Be Determined
Physics operator summary for 950202

EO: Silva/Bertilino
PO: Goetz
SL: Lipschultz

Run 950202 was in support of Mini-Proposal #039 - Effect of Divertor Geometry
on Detachment. The goal of this mini-proposal is to compare the effect of
divertor geometry on the critical density for detachment and the
characteristics of the detachment.

Program for this run:
- Setup a lower SN discharge with Ip=0.8MA, NL_04=0.7e20, and outer
strike point on probe 2
- Raise density in shotwise steps of 0.2e20 to at least 1.5e20
- Change Ip to 0.5MA and repeat
- Change to outer strike point sweeping about probe 8 and repeat

This program was completely carried out (but only because slot operation was
not an original goal of the experiment). See the Session Leader's summary to
find out how this program was carried out and for preliminary results.

Some things discovered today:
1) A very reliable day today. Plasmas were obtained on 34 of 36 shots.
The dud was due to an engineering oversight and the fizzle was due
to a slow current rise. Prior to the fizzle, the A_SIDE plenum
pressure was raised by 3PSIA and the current rise was slower than
any other during the day. Lowering the voltage on the PG3 waveform
by 3 volts allowed the run to continue uninterrupted.
2) With the line-density (NL_04) less than 0.7e20, the plasmas ramp all
the way down. With the density above this level, the plasma will
disrupt because of a shark fin. The time of disruption moves earlier
with an increase in the density. Somehow, the density needs to be
removed more quickly to prevent these fins. On a related note,
lowering the proportional gain on the fast ZCUR wire to 3. helps
control a oscillation in the z-position at 'high' densities.
3) Once again there was a mystery shot in which the plasma was being
fueled by the inner wall. From H-alpha reticon data, it appears that
a MARFE was trapped on the inner wall. When the MARFE drops into the
divertor, fueling returns to normal and all is well with the
controllers. In an attempt to smooth out the CLEARIN, the turn-on of
the integral gain was delayed until 0.45sec. This indeed did remove
the overshoot in the inner gap, but seems to have trapped the MARFE
on the inner wall. Turning on the integral gain at 0.375 solved this
problem for the rest of the run.
4) The STRKPSI controller was used extensively today with varying
reference points. Strike point sweeping was also performed today
using the same controller. Operation with constant outer strike point
at probe 2, and sweeping about probe 2 and probe 8 were successful.
These sweeps were done at 0.8 and 0.5MA. An attempt to operate with
a slot divertor was unsuccessful. Programming for -.015 with probe 1
as the reference point was employed together with asking for a negative
RXL. A suggestion to play with the EF4 was not attempted due to time
limitations.
5) Much twiddling was done with CLEARIN, RCUR, and the x-point controllers
to try and compensate for the sweeping of the strike point in order to
give the FSP a stationary target plasma. The STRKPSI controller wins
out at the expense of the gaps and the x-point location. So I would
recomment against using these shots unless the Session Leader insists
upon everything being constant.
6) A very difficult time dealing with hard x-rays today. Raising the
fill seemed to help the problem, while fiddling with the early gas
did not. The run began with the fill pressure at 1.5e-5 and ended
at 2.0e-5. After shot 028, the hards were gone with no further
tweaking necessary (or for that matter, no tweaking stopped the
hards). The vacuum shop was chasing an argon leak all day, and
whether or not this argon was the hard x-ray producer is not at all
clear.

Engineering, computing, and diagnostics today: Engineering problems today
include the EF1L going to zero demand during the shot (leading to
disruptions shots 003 & 029) and the EF2's not being under hybrid
control. IGOR ran well today, there were no hangs due to the speed
of the servers. However, SCSI CAMAC suffered a vapor lock and all
SCSI data were lost on shot 009. The batch queues died after shot 008
and most analysis jobs didn't run. Diagnostics ran well today.

Scorecard: 36 shots = 34 plasmas + 1 fizzles + 1 p.s. dud

Shot summary for Run 950202

Reload of 950131016

Changes to shot 950131016:
reference on STRKPSI(W12) = (0.624,-0.540)
NL_04 drawn to 0.7e20 from 0.4 to 1.0 sec
CLEARIN extended to 1.05sec
RXL = -.005

Shot change result
____ _____ ______
1 see above dud - EF2's under PLC control

2 no changes plasma - all the way down
strike point and gaps o.k.

3 enable B_SIDE_UPPER & B_SIDE_LOWER plasma - disr. @ 0.6
Ip rolls over @ 0.58 as does
OH1 current

4 raise PG3 early plasma - all the way down
strike point and gaps o.k.
tree troubles for FSP

5 raise PG3 some more in segs 1 & 2 plasma - all the way down
strike point and gaps o.k.

6 raise PG3 some more in segs 1 & 2 plasma - all the way down
some hards; moly down
strike point o.k.

7 NL_04=0.9e20; P_CLEARIN=9.; more PG3 plasma - disr. @1.52
still some hards

8 P_0=1.7e-5; NL_04=1.1e20; delay CLEARIN plasma - disr. @ 1.5
I gain until 0.45 RXL far inside this shot

9 CLEARIN I gain on @ 0.375 plasma - disr. @ 1.4
no SCSI CAMAC - missing data

10 physics P gain on RXL=36 plasma - disr. @ 1.42
gaps & strike o.k.
better on RXL

11 physics P gain on RXL=48; NL_04=1.3e20 plasma - disr. @ 1.43
gaps & strike o.k.
RXL = 0.56->0.54

12 add 3 PSIA to A_SIDE; NL_04=1.5e20 fizzle - current rise is slow

13 lower PG3 in seg 1 plasma - disr. @ 1.43
lots of hards
hesitation on startup

14 NL_04=1.1e20; raise PG3 in seg 1 plasma - disr. @ 1.44
STRKPSI(W12)=-2e-3@0.5;+1.5e-3@.75;0@1. good sweep of strike; gaps o.k.

15 NL_04=1.3e20; raise PG3 in seg 1 plasma - disr. @ 1.4
sweep, gaps, & RXL o.k.
still lots o' hards

16 NL_04=1.1e20; more PG3 @ .03 plasma - disr. @ 1.45
STRKPSI(W12)=-2e-3@.6;+3e-3@.82;0@1.0 some hards remain

17 Ip=0.5MA; more PG3 @ .03 plasma - disr. @ 1.19
right gap changing; good sweep

18 P_0=1.8e-5; NL_04=0.9e20 plasma - disr. @ 1.21
STKRPSI(W12)=-1e-3 @ 1. right gap changing; good sweep

19 NL_04=0.7e20; more PG3 @ 0.08 plasma - disr. @ 1.38
RCUR=0.655->0.657->0.655 RCUR progr. wrong

20 RCUR=0.653->0.649->0.653 plasma - disr. @ 1.36
P_0=1.9e-5 one burst of hards
outer gap steady at 1.4

21 RCUR=0.65->0.646->0.65 plasma - disr. @ 1.38
P_0=2.0e-5 still hards
o.gap=1.6->2->1.6; i.gap=1.4

22 RCUR=0.648->0.646->0.648; CLEARIN=0. plasma - all the way down
fewer hards
o.gap=2; i.gap=1.7->1.5

23 NL_04=0.5e20; RCUR=0.648 plasma - all the way down
gaps, sweep o.k.

24 NL_04=0.6e20 plasma - all the way down
good target plasma

25 NL_04=1.1e20 plasma - disr. @ 1.02
plasma edge moving by a few mm

26 NL_04=0.9e20 plasma - disr. @ 1.45
o.k. target

27 NL_04=1.1e20 plasma - disr. @ 0.96
STRKPSI(W12)=-1.5e-3 from 0.5 to 1. not a slot divertor
STRKPSI(W12)->(RSOUT=.626,ZSOUT=-.552)

28 NL_04=0.9e20; RXL=-.01 plasma - disr. @ 1.47
not a slot

29 load STRKPSI(W12) from 950131027 plasma - disr. @ 0.68
RXL=0->-.002 @ 1sec EF1L goes bad @ 0.6

30 no changes plasma - disr. @ 1.42
outer and inner gaps changing

31 RCUR=.648->.645->.648 plasma - disr. @ 1.4
STRKPSI=-.005@.6; +.002@.75; -.005@.95 still moving too much for FSP

32 add point in CLEARIN=+.01 @ .75sec plasma - disr. @ 1.36
still moving but FSP got in

33 NL_04=1.1e20; P=3 @ 0.8 on ZCUR(W3) plasma - disr. @ 1.29
P gain change reduced osc.

34 P=3 @ 0.5 on ZCUR(W3) plasma - disr. @ 1.31
P gain change worked well

35 NL_04=0.7e20 plasma - all the way down

36 NL_04=0.8e20 plasma - disr. @ 1.42

Session Leader Comments
Feb 2 1995 08:27:15:930AMBruce Lipschultzrun 950202

Engineering operator: F. Silva
Physics operator J. Goetz
Session leader BLip

This run will be a continuation of mini-proposals 39
('effect of geometry on divertor detachment')with a sidetrack
to delve into some details of mp #81 - 'effect of strike point position
on the extent of detachment'.
The plan is to start out at 800 kA with the outer strike point
on probe 2 and constant low density (nl04=0.7e20) and increase the
density by 0.2 each shot for at least 5 shots. If this is successful
we will change the plasma current to 500 kA and repeat.

Feb 2 1995 08:49:03:270AM950202001Bruce Lipschultzshot 1: dud because EF2 not turned on

Feb 2 1995 08:50:57:900AM950202002Bruce Lipschultzshot 2: Fine shot at nl04= 20.7e20. Probe will fire the next shot.

Feb 2 1995 08:51:15:400AM950202002Bruce Lipschultzshot 2: Fine shot at nl04= 0.7e20. Probe will fire the next shot.

Feb 2 1995 09:25:41:400AM950202005Bruce Lipschultzshot 5: shot fine except for Moly peak early in time. We are
still having probe problems. One more time with feeling.

Feb 2 1995 09:43:08:910AM950202006Bruce Lipschultzshot 6: shot went in fine, nl04=0.7. Next shot nl04=0.9

Feb 2 1995 09:54:46:450AM950202007Bruce Lipschultzshot 7: fine shot at nl04=0.9e20. probe scan fine as well. next
shot at nl04=1.1e20.

Feb 2 1995 10:21:17:050AM950202008Bruce Lipschultzshot 8: very strange shot. The footprint of Isat on the outer divertor
shows a major change at ~.85 sec. There appears to be a MARFE during most
of the shot that doesn't slip into the divertor until then. The MARFE
apparently causes most of the divertor to apper to be detached.

Feb 2 1995 10:40:35:850AM950202009Bruce Lipschultzshot 9: The shot went fine but no data because the
camac did not initialize. TWKF has fixed this problem and we will
redo the shot.

Feb 2 1995 10:51:03:640AM950202010Bruce Lipschultzshot 10: Finally we got the nl04=1.1e20. Probe went in fine and we will
raise the density for the next shot.

Feb 2 1995 10:52:33:990AM950202010Bruce Lipschultzshot 10: Finally we got the nl04=1.1e20. Probe went in fine and we will
raise the density for the next shot.

Feb 2 1995 11:01:10:970AM950202011Bruce Lipschultzshot 11: Finally we got the nl04=1.3e20. Detachment even further up the
plate to somewhere around probe 6-7. Probe went in fine and we will
raise the density for the next shot.

Feb 2 1995 11:22:49:070AM950202012Bruce Lipschultzshot 12: fizzle, gas too high

Feb 2 1995 11:32:02:870AM950202013Bruce Lipschultzshot 13: nl04=1.5e20. Lots of hard x-rays. There does not seem to be much
of a difference in detachment profile from the next lower density
shot (11, nl04=1.3e20). We will have to wait for processed data. Next
shot we will go back to nl04=1.1e20 and sweep the strike point around
probe 2 (from probe 1 to 3 and back to 2) to better understand the
profile shape on the divertor.

Feb 2 1995 11:33:22:840AM950202013Bruce Lipschultzshot 13: nl04=1.5e20. Lots of hard x-rays. There does not seem to be much
of a difference in detachment profile from the next lower density
shot (11, nl04=1.3e20). We will have to wait for processed data. Next
shot we will go back to nl04=1.1e20 and sweep the strike point around
probe 2 (from probe 1 to 3 and back to 2) to better understand the
profile shape on the divertor.

Feb 2 1995 11:50:30:380AM950202014Bruce Lipschultzshot 14: sweep of strike point went fine. nl04=1.1e20. Peak in
pressure profile moves up and down the plate. next shot same sweep but
nl04=1.3e20.

Feb 2 1995 11:58:27:960AM950202015Bruce Lipschultzshot 15: seep of strike point with nl04=1.3e20. next shot sweep a little
further (to probe 5) and back to nl04=1.1e20.

Feb 2 1995 12:24:20:240PM950202016Bruce Lipschultzshot 16: Very nice sweep with nl04=1.1e20. We see the peak in Isat move
up to probe 5 from probe 4 and back.

Feb 2 1995 12:35:48:480PM950202017Bruce Lipschultzshot 17: 500 kA, nl04=1.1e20. This shot has detachment all the way up
the inclined plate.

Feb 2 1995 12:45:44:810PM950202018Bruce Lipschultzshot 18: nl04=0.9e20, swept strike point. Detachment through probe 7.
lower the density more on the next shot.

Feb 2 1995 12:58:23:100PM950202019Bruce Lipschultzshot 19: nl04=0.7e20. This shot is probably not useful. The outer gap is
too small (5mm) and there is an event at .82 sec which changes the
profile in the divertor. We will repeat this shot.

Feb 2 1995 01:15:28:620PM950202020Bruce Lipschultzshot 20: Better but outer gap too small still. We will repeat once
again - nl04=0.7e20.

Feb 2 1995 01:29:07:600PM950202021Bruce Lipschultzshot 21: still settling the gap. Also it appears that the Ar level in
the machine is too high - possible inner seal leak. We will repeat
this shot once again without Ar and hopefully better gap control.
Still at nl04=0.7e20.

Feb 2 1995 01:44:01:390PM950202022Bruce Lipschultzshot 22: This shot looks pretty good at nl04=0.7e20. We will lower the
density on the next shot. Ar off for this one and next.

Feb 2 1995 01:56:51:660PM950202023Bruce Lipschultzshot 23: No detachment at nl04=0.5e20. Gaps are good and we will keep
the Ar off until the end of this density scan. Next shot nl04=0.6e20.

Feb 2 1995 02:13:47:050PM950202024Bruce Lipschultzshot 24: nl04=0.6e20 to try to zero in on threshold better.There appears
to be a slight amount of detachment on this shot. Back to repeat
nl04=1.1e20 without Ar next shot.

Feb 2 1995 02:27:25:420PM950202025Bruce Lipschultzshot 25: detached up through probe 7. nl04=1.1e20.

Feb 2 1995 02:38:20:630PM950202026Bruce Lipschultzshot 26: nl04=0.9e20, detachment up through probe 7. next shot on to
slot divertor.

Feb 2 1995 03:04:44:670PM950202027Bruce Lipschultzshot 27: tried to switch to slot w/ne04=1.1e20. However we don't
seem to have moved the separatrix far enough. Detached up
through probe 7. One more try for slot.

Feb 2 1995 03:33:39:360PM950202029Bruce Lipschultzshot 29: flat-plate started ok but EF1 gave out so the plasma disrupted
at .67 sec. Try again with probe as well.

Feb 2 1995 03:54:46:630PM950202030Bruce Lipschultzshot 30: We appeared to get the required sweep. However, the scanning
probe is not able to reach this plasma at all times. nl04=0.9e20.
We will try to hold the separatrix position more constant for the
probe and repeatthe shot. There does not appear to be any detachment.

Feb 2 1995 04:02:57:560PM950202031Bruce Lipschultzshot 31: Flat-plate again ok at nl04=0.9e20. Injection at 0.85 sec which
interrupts the probe scan. We will repeat and try to get the position
of the plasma and probe more appropriate.

Feb 2 1995 04:17:08:950PM950202032Bruce Lipschultzshot 32: nl04=0.9e20, no injections. Probe went in and got 2 good
scans. We will now go to higher density.

Feb 2 1995 04:34:46:140PM950202033Bruce Lipschultzshot 33: Very nice sweep. nl04=1.1e20. Looks like detachment on
probe 8. However the probe was not properly enabled that shot - no FSP.

Feb 2 1995 04:49:38:570PM950202034Bruce Lipschultzshot 34: nl04 = 1.1e20, detachment and FSP made scan. We will go to
lower density next shot to make sure we have the detachment
threshold correct.

Feb 2 1995 05:03:39:230PM950202035Bruce Lipschultzshot 35: nl04=0.7e20, no detachment obvious. FSP scan went all right.
However, the signals on probe 8 appear a little awry. We will repeat
with slightly higher density.

Feb 2 1995 06:08:50:480PM950202036Bruce Lipschultzshot 36: good profile at probe 8 during sweep for nl04=0.8e20.

Physics Operator Comments
Feb 2 1995 08:10:14:270AMJohn GoetzRun 950202
MiniProposal #039 - Effect of Divertor Geometry on Detachment

Run Plan:
-develop lower SN discharge with outer strike-point
located near probe 2 and with Ip=0.8MA and
NL_04=0.7e20
-raise density in steps of 0.2e20 until at least 1.5e20
-change Ip to 0.5MA and repeat
-develop lower SN discharge with outer strike-point sweeping
about probe 8 and repeat the above steps

Feb 2 1995 08:37:23:430AM950202001John GoetzShot 950202001:
Cold start hybrid - all matrices respond
Load from 950131016 and make these changes:
reference on STRKPSI(W12) = (rsout=0.624,zsout=-0.534)
NL_04=0.7e20
RXL=-.005
CLEARIN extended to 1.05sec

Results:
DUD - EF2's under PLC control

Feb 2 1995 08:47:49:980AM950202002John GoetzShot 950202002:
no changes

Results:
plasma - all the way down
strike-point fairly solid on probe 2
gaps o.k.

Feb 2 1995 09:09:39:250AM950202003John GoetzShot 950202003:
enable B_SIDE_UPPER
enable B_SIDE_LOWER

Results:
disruption @ 0.6
Ip begins to roll over @ 0.58 coincidence with a change in OH1
current

Feb 2 1995 09:11:39:270AM950202004John GoetzShot 950202004:
raise PG3 early to combat large moly influx

Results:
plasma - all the way down
strike point o.k. - gaps o.k.
troubles with tree for FSP control

Feb 2 1995 09:27:00:520AM950202005John GoetzShot 950202005:
raise PG3 some more in segs 1 & 2 to combat large moly influx

Results:
plasma - all the way down
strike point and gaps are o.k.
moly down just a bit
still no FSP

Feb 2 1995 09:42:59:830AM950202006John GoetzShot 950202006:
raise PG3 still more in segs 1 & 2 to combat large moly influx

Results:
plasma - all the way down
moly down, but some hards around
strike point o.k. - inner gap becomes 1 mm smaller thru shot

Feb 2 1995 09:54:40:940AM950202007John GoetzShot 950202007:
raise PG3 still more in segs 1 & 2 to combat hards
NL_04=0.9e20
P_CLEARIN=9.

Results:
plasma - disr. @ 1.52
still some hards
strike point o.k.

Feb 2 1995 10:25:04:460AM950202008John GoetzShot 950202008:
P_0=1.7e-5
NL_04=1.1e20
delay CLEARIN I gain until 0.45

Results:
plasma - disr. @ 1.5
MARFE does not drop into divertor until 0.84 -
very wierd shot
lower x-point is riding the inner nose

Feb 2 1995 10:39:53:830AM950202009John GoetzShot 950202009:
CLEARIN I gain until 0.375

Results:
Plasma - disr. @ 1.4
no SCSI CAMAC - missing many pieces of data
nice gaps and no trapped MARFE

Feb 2 1995 10:48:47:780AM950202010John GoetzShot 950202010:
Physics P gain on RXL = 36

Results:
plasma - disr. @ 1.42
nice shot
gaps o.k. - strikepoint o.k.
a bit better on RXL

Feb 2 1995 11:01:43:370AM950202011John GoetzShot 950202011:
NL_04 = 1.3e20
Physics P gain on RXL = 48

Results:
plasma - disr. @ 1.43
gaps and strike o.k.
RXL = 0.56 -> 0.54

Feb 2 1995 11:17:28:340AM950202012John GoetzShot 950202012:
NL_04 = 1.5e20
add 3PSIA D2 to A_SIDE

Results:
fizzle - current rises too slowly
must have been too much gas from the increase in pressure

Feb 2 1995 11:33:06:250AM950202013John GoetzShot 950202013:
lower PG3 in segment 1

Results:
plasma - disr. @ 1.43
lots of hards
hesitation on ramp-up @ .015
gaps & strike o.k.

Feb 2 1995 11:46:49:640AM950202014John GoetzShot 950202014:
NL_04 = 1.1e20
raise PG3 just a bit in seg 1
sweep outer strike; STRKPIS(W12) = -2e-3@0.5; +1.5@0.75; 0@1.0

Results:
plasma - disr. @ 1.44
fewer hards - but they're still there
good sweep of strike; gaps o.k.

Feb 2 1995 11:57:46:800AM950202015John GoetzShot 950202015:
NL_04 = 1.3e20
raise first two points of PG3 just a bit in seg 1


Results:
plasma - disr. @ 1.4
good sweep of strike; gaps o.k.; RXL o.k.
still plenty of hards

Feb 2 1995 12:30:51:980PM950202016John GoetzShot 950202016:
NL_04 = 1.1e20
raise PG3 around .03sec


Results:
plasma - disr. @ 1.45
hards - but fewer
good strike sweep

Feb 2 1995 12:31:46:670PM950202017John GoetzShot 950202017:
Ip=0.5MA
more PG3 @ .03

Results:
plasma - disr. @ 1.19
hards - but fewer
good strike sweep
right gap decreases, then increases

Feb 2 1995 12:44:30:430PM950202018John GoetzShot 950202018:
P_0=1.8e-5
NL_04 = 0.9e20
STRKPSI(W12) = -1e-3 @ 1.0

Results:
plasma - disr. @ 1.21
hards dump @ 0.1
outer gap shaking

Feb 2 1995 01:01:43:030PM950202019John GoetzShot 950202019:
NL_04 = 0.7e20
more PG3 @ 0.08
RCUR=0.655->0.657->0.655 to correct outer gap drift

Results:
plasma - disr. @ 1.38
wrong RCUR programming - plasma moved closer to FSP

Feb 2 1995 01:13:23:010PM950202020John GoetzShot 950202020:
RCUR=0.653->0.649->0.653 to correct outer gap drift
P_0=1.9e-5

Results:
plasma - disr. @ 1.36
outer gap ~ 1.4cm and fairly flat
only one burst of hards

Feb 2 1995 01:28:25:570PM950202021John GoetzShot 950202021:
RCUR=0.65->0.646->0.65 to increase outer gap
P_0=2.0e-5

Results:
plasma - disr. @ 1.38
outer gap =1.6->2->1.6; inner gap = 1.4
sweep and strike o.k.

Feb 2 1995 01:45:05:550PM950202022John GoetzShot 950202022:
RCUR=0.648->0.646->0.648 to increase outer gap
CLEARIN = 0.

Results:
plasma - all the way down
fewer hards
outer gap 2.0 and flat - inner gap 1.7->1.5

Feb 2 1995 01:56:21:350PM950202023John GoetzShot 950202023:
RCUR=0.648
NL_04 = 0.5e20

Results:
plasma - all the way down
fewer hards still
gaps o.k.; sweep o.k.; good target for FSP

Feb 2 1995 02:09:32:530PM950202024John GoetzShot 950202024:
NL_04 = 0.6e20

Results:
plasma - all the way down
gaps, strike, target are o.k.

Feb 2 1995 02:27:32:810PM950202025John GoetzShot 950202025:
NL_04 = 1.1e20

Results:
plasma - disr. @ 1.02
plasma boundary moving a few mm

Feb 2 1995 02:41:04:440PM950202026John GoetzShot 950202026:
NL_04 = 0.9e20

Results:
plasma - disr. @ 1.45
o.k. target

Feb 2 1995 03:01:09:850PM950202027John GoetzShot 950202027:
NL_04 = 1.1e20
STRKPSI(W12)=-1.5e-3 from 0.5 to 1.0
STRKPSI(W12) reference -> (RSOUT=0.626,ZSOUT=-.552)

Results:
plasma - disr. @ .96
not a slot divertor

Feb 2 1995 03:19:36:060PM950202028John GoetzShot 950202028:
NL_04 = 0.9e20
RXL = -.01

Results:
plasma - disr. @ 1.47
only a slot for a few msec

Feb 2 1995 03:32:29:370PM950202029John GoetzShot 950202029:
STRKPSI(W12) ref -> (RSOUT=.6144,ZSOUT=-.4367)
load STRKPSI programming from segment 2 of 950131027
RXL = 0->-.002 @ 1sec

Results:
plasma - disr. @ 0.68
EF1L messes up @ 0.6sec
(the same was true on 950202003, but was not noticed)

Feb 2 1995 03:48:54:250PM950202030John GoetzShot 950202030:
no changes

Results:
plasma - disr. @ 1.42
moly injections @ .35 & .45
outer gap 2->1.4->2; inner gap drooping
good sweep of strike

Feb 2 1995 04:04:11:110PM950202031John GoetzShot 950202031:
RCUR=.648->.645->.648
strike sweep from -.005@.6 to +.002@.75 to -.005@.95

Results:
plasma - disr. @ 1.4
moly inj. @ 0.85
plasma still moving quite a bit wrt FSP

Feb 2 1995 04:17:45:470PM950202032John GoetzShot 950202032:
add point in CLEARIN @ 0.75 to mimic strike sweep

Results:
plasma - disr. @ 1.36
still a moving target but FSP got in anyway

Feb 2 1995 04:33:57:910PM950202033John GoetzShot 950202033:
NL_04=1.1e20
P gain on ZCUR(W3) = 3 @ 0.8sec

Results:
plasma - disr. @ 1.29
P gain change helped stop the z-oscillation
FSP did not fire

Feb 2 1995 05:00:57:010PM950202034John GoetzShot 950202034:
P gain on ZCUR(W3) = 3 @ 0.5sec

Results:
Plasma - disr. @ 1.31
P gain change on ZCUR(W3) works well
FSP fired

Feb 2 1995 05:01:39:580PM950202035John GoetzShot 950202035:
NL_04=0.7e20

Results:
Plasma - all the way down
FSP fired

Feb 2 1995 05:09:47:760PM950202036John GoetzShot 950202036:
NL_04=0.8e20

Results:
plasma - disrupts @ 1.42
strike sweep acceptable

Engineering Operator Comments
ShotTimeTypeStatusComment
108:24:16:590AMPlasmaOkengineering goof, tmx on plc
208:34:29:840AMPlasmaOkno faults plasma
308:48:27:520AMPlasmaOkcomm fault ef1l
408:59:55:570AMPlasmaOkno faults, plasma
509:17:59:220AMPlasmaOkno faults, plasma
609:29:51:630AMPlasmaOk
709:42:48:990AMPlasmaOkno faults, plasma
809:55:21:620AMPlasmaOkno faults
910:25:30:100AMPlasmaOkno faults, plasma
1010:40:08:950AMPlasmaOkno faults, plasma
1110:52:25:380AMPlasmaOkno faults plasma
1211:05:12:670AMPlasmaOkno faults no bd
1311:19:00:510AMPlasmaOkno faults plasma
1411:34:02:250AMPlasmaOkno faults
1511:47:57:980AMPlasmaOkno faults plasma
1612:01:36:740PMPlasmaOkno faults plasma
1712:16:40:420PMPlasmaOkno faults, plasma
1812:32:19:570PMPlasmaOkno faults, plasma
1912:48:05:310PMPlasmaOkno faults, plasma
2001:00:28:770PMPlasmaOkno faults
2101:15:43:580PMPlasmaOkno faults
2201:31:36:080PMPlasmaOkno faults
2301:45:49:950PMPlasmaOkno faults
2401:59:50:030PMPlasmaOkno faults
2502:16:05:130PMPlasmaOkno faults
2602:30:31:440PMPlasmaOkno faults
2702:45:28:980PMPlasmaOkoh2l comm fault after disruption
2803:03:03:160PMPlasmaOkno faults
2903:22:33:940PMPlasmaBadef1l comm fault
3003:34:05:690PMPlasmaOkno faults
3103:49:58:270PMPlasmaOkno faults
3204:06:06:270PMPlasmaOkno faults
3304:20:47:350PMPlasmaOkno faults
3404:37:05:530PMPlasmaOkno faults
3504:51:25:710PMPlasmaOkno faults
3605:05:49:930PMPlasmaOkno faults