Alcator C-Mod Run 950216 Information

Miniproposals

Miniproposal:

Date Filed:

Title:

First Author:

Session Leader: Gary McCracken (shots 1-34)

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

Engineering Operator Run Comment
Silva-Daigle/Golavatos-McCracken

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:12:273PM

Author: To Be Determined

Session Leader Report for Run 950216
EO F Silva / J Daigle
PO S Golovato
SL G McCracken

MP 082: Isotope exchange experiment

Purpose:1. To measure the evolution of the isotopic composition in the
plasma both during a discharge and from shot to shot when the fuelling
is changed from deuterium to hydrogen and back again.
2. To compare the Mo sputter rate in hydrogen and deuterium
3. To obtain confinement data in hydrogen for the database

A single null diverted discharge was set up with the strike point on
probe 2 of the outer target plate. Four good discharges at nel04=7 to8e19 were
taken in D_2 while the diagnostics were set up. The main measurements were
with the CX analyser and the oma spectrometer looking at Halpha during the shot
and the Dycor RGA looking at the outgassing after the shot. Shot 007 was the
first in H_2. The ratio D/H+D fell from ~99% in shot 006 to 50% at the
beginning of the diverted phase of shot 007 ,0.5 s, and then rose to ~67% at
the end of the shot. This behaviour was observed both with the CX analyser and
the Halpha lines. The RGA indicated a D/H+D ~60% during the outhgassing.
A series of similar low density shots were run and by shot 010 D/H+D
changed from 25% to 50% during the shot and was 25-35% during outgassing. By
shot 018 the ratio had reached 10% during the shot and 20% during outgassing.
We then did a density scan from 0.6 to 2e20. Some difficulty was had
with the high density discharges and we had a few disruptions. The MoI on the
inner wall was monitored as a function of density while D/H+D ratios continued
to be taken with th CX and the RGA. The D/H+D ratio did not appear to be
sensitive to density and continued to fall by 1-2%/discharge reaching 15% on
the RGA by shot 24. Preliminary analysis indicated little change of taue with
isotopic mass (M Greenwald ).
Shot 025 was a gas calibration and the first shot back in D_2 was 026.
The D/H+D =50% during the shot and 40% on the RGA. By shot 033 the ratio had
risen to 90 % during the shot and 75% on the RGA. Rejean reported that the
change back to D2 was same as the change from D_2 to H_2.
During the change back to D_2 (shots 27 to 33) the first preliminary
puffs of N2 into the plasma were tried using B-side upper valve (3psi, 100V,
pulse length 20 - 60 ms at 0.5 s). Lines of Li like N were identified on the
McPherson and some NII lines were seen with oma. The N lines increased rapidly
to a maximum and then decayed exponentially in less than 100 ms indicating the
low recycling expected from published data.

Much analysis remains to be done but I think that the miniproposal could be
said to have been successfully completed

Shot Summary
001 Disruption at 0.5 s.
002 Fizzle
003 Good shot. nel04=8e19. Nice Halpha data from the oma. No data from CX or
RGA
004 Good shot. nel04=7.9e19. Good data on CX, oma and RGA. Not fully
diverted until 0.5 s
005: Good shot. nel04=7.1e19. All data looks good
006 Good shot. No density trace. Took FSP scan this shot

007 First shot with all hydrogen fill. Gas fill reduced to get breakdown
Hard x-rays. nel05= 5.8e19, falling during the pulse to 4.5e19
The D/D+H =0.5 on the RGA after the shot and also on the oma
CX indicates the the H/D ratio falls from 80% to 40% during the shot.
008 Good shot. H2 .nel04= 5.7e19. D/D+H=0.33 on RGA.
009 Good shot. H2 . nel04= 8.2e19. Data look fine D/D+H =0.4 to 0.7
010 Good shot. H2. nel04= 5.7e19 Good data.D/(H+D) Starts at 40%, dips
to 25% and then rises again to nearly 40% after 10 mins
011 Good shot. H2. nel04= 5.4e19 Good data.D/(H+D) Starts at 38%, dips
to 22% and then rises again to nearly 37% after 10 mins
012 Good shot. H2. nel04=5.4e19 Good data. D/(H+D) =32% after 10 mins
013 Good shot H2. Disruption at 0.6 s. D/(H+D) =30% after 10 mins
014 H2. Good shot again. .nel04=6e19 D/(H+D) =25% after 10 mins
015 H2. . nel04=7.7e19 D/(H+D) = 23 % after 10 mins.
Not much change from shot to shot.
016 H2. Good shot .nel04=4.7e19 D/(H+D) = 23 % after 10 mins.
017 H2. Good shot nel04=6.3e19
018 H2. Good shot .nel04=6.0e19 Change oma to lamda=3900 to look at MoI.
Lovely spectra at about 0.4 s D/(H+D) = 21 % after 10 mins.

019 H2. Good shot .Start of density scan, nel04=1.0e20 disruption in the
rampdown. oma lamda=3900; good MoI. spectra; RGA D/(H+D) = 20 % after 10 mins.
.
020 H2. Planned to go to 1.5e20; Disrupts at 0.4 s; RGA D/(H+D) = 18 %
after 10mins.
021 H2. Achieved 1.5e20 this time Disrupted at 1 s.
MoI data early (~0.3 s) on oma but large high n H Balmer lines later, ~0.36 s
RGA D/(H+D) = 17 % after 10 mins. .
022 H2. reached 2e20 at o.7 s Disrupted at 0.9 s.
MoI data early (~0.3 s) on oma
RGA D/(H+D) = 15 % after 10 mins. .
023 H2. End of density scan. Return to low density nel04=0.6e20
Large Mo peaks at 0.45 s; RGA D/(H+D) = 15 % after 10 mins. .
024 H2. nel04=0.54e20; oma back on Halpha. good data
RGA D/(H+D) = 16 % after 10 mins. .

025 Gas calibration shot, H2. No plasma. Fizzle detector off
Good data on the ratiomatic also on the RGA

026: First shot back with D2 as the fill gas. Tried to repeat shot 006,
Good shot. Density nel04 about 8e19 , although rising a bit through thepulse
027 D2. Density nel04 about 8e19 ,D/H+D =0.5
First Nitrogen injection through Bside upper.Plenum pressure 3 psi, Pulse
length 20ms at 0.5 s. N2 masked by large Mo injection at 0.5 s The oma was at
400 nm to try and see the NII line at 399.5 nm. It was barely visible
028 D2, Good shot. nel04 about 8.2e19 ,
D/H+D =0.6 and is fairly constant .Same N2 puff; oma at 460 nm to see NII at
463 nm. Small peak at 0.5 s falling in 100 ms.
029 D2, Good shot. Density nel04 about 8.2e19 ; D/H+D =0.63 and is fairly
constant Nominally the same N2 puff. oma at 345nm to look for NIV lines.
There
is a reasonable peak.
030 D2, Good shot. Density nel04 about 8.2e19 , D/H+D =0.67 and is fairly
constant N2 puff.increased to 40 ms. Still 100 V 3.2psi plenum pressure
oma lamda at 3930 to look at NII again at 3995. A clear peak is seen at o.5 s,
about 150 counts high.
031 D2, Good shot. Density nel04 about 8.2e19 , D/H+D =0.71
N2 puff still 40 ms. 100 V 3.2psi plenum pressure
N2 puff still 40 ms. 100 V 3.2psi plenum pressure
oma lamda at 6560 to look at Halpha good data
032 D2, Good shot. Density nel04 about 8.2e19 , D/H+D =0.74
N2 puff still 60 ms. 100 V 3.2psi plenum pressure
oma lamda at 6560 to look at Halpha good data
033 D2, good shot nel04 about 8.2e19 ??, D/H+D =0.75
034 D2 gas calibration shot, no plasma, fizzle detector off. Ratiomatic
data but no RGA

Physics Operator Summaries

Entered: Jul 7 2004 04:36:53:223PM

Author: To Be Determined

Physics Operator Summary - Run 950216

SL - McCracken
PO - Golovato
EO - Daigle/Silva

This was a very successful run with all goals and then some achieved. After a first
shot early disruption due to too much early gas and an unannounced modification to
the OH2 supplies (which was removed after shot 1) and a fizzle on shot 2, we had
30 straight plasmas, with 2 gas puff only shots (25 and 34).

We started by loading segment 2 of shot 950202007 which had the outer strike point
at FMP2, as desired by the session_leader. Changes to this shot were:

(1) nl_04 programming changed from 9.e19 to 8.e19.
(2) diversion moved to .4 sec from .2 sec by moving clearin ramp
from by this amount of time.
(3) moved clearin integral gain turn on to .5 sec from .3 sec
(4) changed fill to 1.5 from 1.7e-5.

By starting with a fairly old shot (2 weeks old) we had some settings which
had evolved. This can be a problem and both the physics and engineering
operators need to be aware of this, particularly if problems arise.
We had one potential problem that turned out to not be.
Engineering copied in conditions of shot 950202007, as requested.
This shot had ef2 start time of -.4 sec while we now run -.5 sec.
This caused the ef2 supplies to come on hard to the current hey would have
attained more gradually had they come on at -.5 sec. If I had compared the
engineering data given me this morning with one from yesterday, I might have
noticed differences like this and would have asked if it mattered.
Another problem was that the gas programming in segment 1 was inherited from
the last shot of yesteday, when the plemun pressure was dowm to arouund 13#.
Since the a-side plenum pressure started at 20.3# of deuterium today, we were
overgassing the plasma early, leading to the initial disruption. We then
cut in sgment 1 from shot 20 of the previous day and reduced the gas even
more (see physics operator logbook entries for details). This worked fine.

The shots were ramping all the way down exept at the highest densities.
It stayed diverted virtually the whole time, the x-point moving in
and the strike points moving up the inner wall. This rampdown was
developed presumably by John Goets on 950202 since we started with
shot 7 from that day.

The run physics goals and accomplishments can be found in the session_leader
logbook entries and the session_leader run summery.

On shot 4 the diversion was moved to about .5 sex by moving the clearin ramp
out to .45 sec and turning off integral gain. On shot 5 the density feedback was
turned off and the M_out_14 signal copied into the a-side gas valve voltage
programming. On shot 7 we switched to hygrogen puffing from a-side with the
gas controlled by the voltge programming (feedforward). The prefill pressure
was lowered to 1.2e-5 from 1.5e-5. Both Wolfe and Horne had found (runs 950110 and
950203) that when running at D/H mixture above 20% H, the prefill had to be lowerred
to avoid fizzles. This was too low with excessive hards on shot 7. It was raised to
1.3e-5 on sot 8 and this proved fine. We played with gas programming over several
shots as the density fell shot-to-shot, trying to keep it roughly constant. The same
programming that gave nl_04 of abut 7.e19 in D gave closer to 5.e19 in H.
The density drifted down shot-to-shot until we got an early disruption on shot 13,
The ef2u supply also behaved strangely on this shot, it's not clear what led to the
disruption. We ran with feedback for the next shot and then cut the M_out_14
signal in for feedforward operation on 17-18. We began a density scan on shot 19
with feedback. Shot 19 disrupted at 1.2 sec from an oh1 software limit inherited from
the old shot we started with. It was raised from 20000 to 26000. We had problems
with disruptions late in the shot at higher densities. The efc gain was 5 (again
inherited from the old shot) while we ran at 4 yerterday. An efc oscillation was
preceeding the disruptions. To achieve higher densities without an early disruption,
the density was brought up along the slope used at lower densities, giving a shorter
flattop at peak density, i.e., from .6 sec at 1.5e20 and .675 sec at 2.e20, the highest
we ran on shot 22. We took 2 more H shots at low density, then did a gas puff only
shot for shot 25, using the feedforward from segment 2 of shot 11. Before switching
back to D for shot 26, we had a cell access to open a manual valve enabling the
nitrogen puff form b-side-upper. We had seen a glowingof the rf antenna tiled early
in the shots all day. We moved the diversion time earlier, by moving the clearin
ramp from 4. to .45 sec to 2. to .25 sec. This eliminated the glowing starting at
shot 27. On shot 28 we went to density feedback at 8.e19 for the rest of the day.
Nitrogen puffs of increasing length were applied at .5 sec over the remaining shots
ot find suitable lines for tomorrows run.
The final shot was again a gas puff only shot in D, using the voltage programming
of segment 2, shot 33. When doing no plasma shots the fizzle detector must be
disabled or the hybrid wont drive the puff valve. This is done in the upper left
corner of the pcs screen, which is live, like the trees. Be careful here not to
leave it disabled for the next operator.

Shot accounting: 31 plasmas
1 fizzle
2 gas puff only shots

Session Leader Comments

Feb 16 1995 08:35:05:120AM Gary McCracken Isotope Exchange experiment
EO F Silva
PO S Golovato
SL G McCracken

MP 082
Purpose:1. To measure the evolution of the isotopic composition in the
plasma both during a discharge and from shot to shot when the fuelling
is changed from deuterium to hydrogen and back again.
2. To compare the Mo sputter rate in hydrogen and deuterium

The main diagnostics for the isotope exchange experiment are the charge
exchange detector, the oma spectrometer looking at Halpha, and the Dycor
RGA looking at the gas released after the shot

Feb 16 1995 05:37:14:290PM Gary McCracken Summary:
Very successful day. 31 plasmas. All 3 diagnostics for the H/D ratio
worked well and appear on first sight to be fairly consistent. The D to
H changeover to deuterium was done for 12 shots after which the D/H+D
ratio had dropped from about 97% to 20% as measured on the RGA. Data
from the oma is still to be analysed. We then did a density scan from
0.6 to 2e20 in H by which time the D/H+D had dropped to 0.15. The
change back to D lasted 8 shots, by which time the D/H+D da risen back
to 0.76. We also did some preliminary N2 puffing to identify lines for
tomorrow. Li like N was seen on the Mcpherson and a NII line on the
oma. The injected gas disappears in less than 100 ms

Feb 16 1995 09:01:48:970AM 950216001 Gary McCracken Disruption at 0.5 s. Apparently a problem with the gas puff during
the pulse.
Note: the plenum pressure for the D2 fill is 20.3 psi

Feb 16 1995 09:06:33:420AM 950216002 Gary McCracken Fizzle

Feb 16 1995 09:31:31:180AM 950216003 Gary McCracken Good shot. Nice Halpha data from the oma. No data from CX as the valve
was not opened. No data from the rga yet. nel04=8e19 , good.
However density is still on feedback and we want it to be preprogrammed
so that we put in a well defined amount of gas
We want to divert a little later so that we reach full
current while still limited in the next shot. Also

Feb 16 1995 09:47:00:000AM 950216004 Gary McCracken Good shot. nel04=7.9e19. but still feedback. Cx data looks good.
RGA taking data; transferred successfully to the vax and available
on the scope. Not fully diverted until 0.5 s, which is fine

Feb 16 1995 09:57:31:080AM 950216005 Gary McCracken Good shot. nel04=7.1e19.Now preprogrammed. Looks good although a
little lower density. All data looks good

Feb 16 1995 10:13:26:550AM 950216006 Gary McCracken Good shot. No density trace. Otherwise fine. Took FSP scan this shot
Change to all hydrogen feed for the next shot.

Feb 16 1995 10:32:54:160AM 950216007 Gary McCracken First shot with all hydrogen fill. Gas fill reduced to get breakdown
Hard x-rays. nel05= 5.8e19, falling during the pulse to 4.5e19
The H/D ratio is about 1:1 on the RGA after the shot and also on the oma
CX indicates the the H/D ratio falls from 80% to 40% during the shot.
Try to raise density in the next shot

Feb 16 1995 10:45:34:400AM 950216008 Gary McCracken Good shot. Second in H2 . Density still low, 5.7e19. H/D ratio about
2:1 on RGA. Increase gas fill slightly in next shot to keep density
constant

Feb 16 1995 11:01:24:120AM 950216009 Gary McCracken Good shot. Third in H2 . Overdid the extra gas puff.
Density went up , 8.2e19e19. Data look fine

Feb 16 1995 11:09:19:510AM 950216009 Gary McCracken RGA H/D ratio 1.5 to 0.4

Feb 16 1995 11:17:52:680AM 950216010 Gary McCracken Good shot. 4th in H2. Density fairly flat at 5.7e Good data.
% of D/(H+D) now available on RGA scope. Starts at 40%, dips
to 25% and then rises again to nearly 40% after 10 mins

Feb 16 1995 11:38:19:660AM 950216011 Gary McCracken Good shot. 5th in H2. Density fairly flat at 5.4e19 Good data.
D/(H+D) Starts at 38%, dips
to 22% and then rises again to nearly 37% after 10 mins

Feb 16 1995 11:44:11:240AM 950216012 Gary McCracken Good shot. 6th in H2. Density fairly flat at 5.4e19 Good data.
D/(H+D) =32% after 10 mins

Feb 16 1995 12:00:14:850PM 950216013 Gary McCracken 7th in H2. Disruption at 0.6 s. Maybe the density is falling too low
We will use density feedback at 6e19 for the next shot hopefully to get
out of trouble.
D/(H+D) =30% after 10 mins

Feb 16 1995 12:16:40:510PM 950216014 Gary McCracken 8th in H2. Good shot again. Have set density feedback.nel04=6e19
We will use the feedback signals to preprogram for the next shot
D/(H+D) =25% after 10 mins

Feb 16 1995 12:35:32:740PM 950216015 Gary McCracken 9th in H2. Good shot .nel04=7.7e19 preprogrammed density. too high
Try to reduce it in next shot
D/(H+D) = 23 % after 10 mins. Not much change from shot to shot.

Feb 16 1995 12:52:36:660PM 950216016 Gary McCracken 10th in H2. Good shot .
nel04=4.7e19 too low
D/(H+D) = 23 % after 10 mins. No change from last shot.

Feb 16 1995 01:01:19:090PM 950216017 Gary McCracken 11th in H2. Good shot .Back to feedback control of density
nel04=6.3e19
D/(H+D) = 22 % after 10 mins. No change from last shot.

Feb 16 1995 01:15:52:700PM 950216018 Gary McCracken 12th in H2. Good shot .Feedback control of density
nel04=6.0e19 Change oma to lamda=3900 to look at MoI. Lovely spectra
at about 0.4 s
D/(H+D) = 21 % after 10 mins. About 1% change from shot to shot.

Feb 16 1995 01:30:58:280PM 950216019 Gary McCracken 13th in H2. Good shot .Feedback control of density. Start of density
scan, nel04=1.0e20 disruption in the rampdown. oma lamda=3900;
good MoI. spectra
RGA D/(H+D) = 20 % after 10 mins. .

Feb 16 1995 01:45:52:050PM 950216020 Gary McCracken 14th in H2. Plan to go to 1.5e20 Disrupts at 0.4 s. Too much gas?
RGA D/(H+D) = 18 % after 10 mins. .

Feb 16 1995 02:06:42:520PM 950216021 Gary McCracken 15th in H2. Achieved 1.5e20 this time Disrupted at 1 s.
MoI data early (~0.3 s) on oma but large high n H Balmer lines later,
~0.36 s
RGA D/(H+D) = 17 % after 10 mins. .

Feb 16 1995 02:24:55:170PM 950216022 Gary McCracken 16th in H2. reached 2e20 at o.7 s Disrupted at 0.9 s.
MoI data early (~0.3 s) on oma
RGA D/(H+D) = 15 % after 10 mins. .

Feb 16 1995 02:38:53:220PM 950216023 Gary McCracken 17th in H2. End of density scan. Return to low density nel04=0.6e20
with feedback. Large Mo peaks at 0.45 s
RGA D/(H+D) = 15 % after 10 mins. .

Feb 16 1995 02:56:39:730PM 950216024 Gary McCracken 18th in H2. Preprogrammed density as in shot 11. nel04=0.54e20
. oma back on Halpha. good data
RGA D/(H+D) = 16 % after 10 mins. .
Next shot will be a gas calibration shot with no plasma. Fizzle
detector off

Feb 16 1995 03:03:43:240PM 950216025 Gary McCracken Gas calibration shot. No plasma. Fizzle detector off
Good data on the ratiomatic also on the RGA

Feb 16 1995 03:25:56:090PM 950216026 Gary McCracken First shot back with deuterium as the fill gas. Try to repeat shot 006,
the last shot we had in D2 with preprogram gas fill.
Good shot. Density nel04 about 8e19 , although rising a bit through the
pulse

Feb 16 1995 03:49:03:770PM 950216027 Gary McCracken Second shot back with deuterium as the fill gas. preprogram gas fill.
Good shot. Density nel04 about 8e19 ,
First Nitrogen injection through Bside upper.Plenum pressure 3 psi,
Pulse length 20ms at 0.5 s.Plan to have line identification on the oma
and the McPherson. The N2 clearly affected the radiation and cooled the
plasma. Seen as lithium like nitrogen on the Mcpherson. It drops to
nearly zero in 100 ms indicating that it is non recycling. The oma was
400 nm to try and see the NII line at 399.5 nm. It was barely visibleat

Feb 16 1995 04:05:47:920PM 950216028 Gary McCracken Third shot back with deuterium as the fill gas. Density feedback.
Good shot. Density nel04 about 8.2e19 ,
D/H+D =0.6 and is fairly constant . Last shot it was 0.5 s
Nominally the same N2 puff. However the effect is much less globally and in the spectra
N2 puff; oma at 460 nm to see NII at 463 nm. Small peak at 0.5 s
falling in 100 ms. The previous global effect in shot 27 may be due to
moly rather than N2

Feb 16 1995 04:18:13:910PM 950216029 Gary McCracken Fourth shot back with deuterium as the fill gas. Density feedback.
Good shot. Density nel04 about 8.2e19 ,
D/H+D =0.63 and is fairly constant .
Nominally the same N2 puff. oma at 345nm to look for NIV lines. There
is a reasonable peak.

Feb 16 1995 04:30:11:500PM 950216030 Gary McCracken 5th shot back with deuterium as the fill gas. Density feedback.
Good shot. Density nel04 about 8.2e19 ,
D/H+D =0.67 and is fairly constant .
N2 puff.increased to 40 ms. Still 100 V 3.2psi plenum pressure
oma lamda at 3930 to look at NII again at 3995. A clear peak is
seen at o.5 s, about 150 counts high.

Feb 16 1995 04:45:08:930PM 950216031 Gary McCracken 6th shot back with deuterium as the fill gas. Density feedback.
Good shot. Density nel04 about 8.2e19 ,
D/H+D =0.71
N2 puff still 40 ms. 100 V 3.2psi plenum pressure
oma lamda at 6560 to look at Halpha good data

Feb 16 1995 04:59:16:260PM 950216032 Gary McCracken 7th shot back with deuterium as the fill gas. Density feedback.
Good shot. Density nel04 about 8.2e19 ,
D/H+D =0.74
N2 puff still 60 ms. 100 V 3.2psi plenum pressure
oma lamda at 6560 to look at Halpha good data

Feb 16 1995 05:13:00:600PM 950216033 Gary McCracken 8th shot back with deuterium as the fill gas. Density preprogrammed
as for shot 026
Good shot. Density nel04 about 8.8e19 but rising during shot ,
RGA D/H+D =0.76
N2 puff still 60 ms. 100 V 3.2psi plenum pressure
oma lamda at 6560 to look at Halpha good data

Feb 16 1995 05:20:16:030PM 950216034 Gary McCracken Gas calibration shot only. No plasma. D2 preprogrammed as for shot 033
Data taken with the ratiomatic and with the RGA

Physics Operator Comments

Feb 16 1995 09:04:01:580AM Steve Golovato Goals of run 950216

Start in deuterium. Get shot with nl_04=8.e19, diverting about
0.4 sec. Remove density feedback (cut M-out signal into voltage
programming). Once conditions established, change to hydrogen
and observe changeover over a number of shots. After this, do density
scan to study H sputtering of Mo.

Starting with shot 950202007 which had strike point at FMP2, as desired
by the session_leader. Changes to this shot were:

(1) nl_04 programming changed from 9.e19 to 8.e19.
(2) diversion moved to .4 sec from .2 sec by moving clearin ramp
from by this amount of time.
(3) moved clearin integral gain turn on to .5 sec from .3 sec
(4) changed fill to 1.5 from 1.7e-5.

a-side plenum pressure 20.3#.

Feb 16 1995 03:55:56:670PM Steve Golovato Note: engineering copied in conditions of shot 950202007, as requested.
This shot had ef2 start time of -.4 sec. we now run -.5 sec.
This turned out not to be a problem but care should be taken by phyics
and engineering operators when fairly old shots are loaded as many
conditions evolve with time. If I had compared the engineering data
sheet given me this morning with one from yesterday, I might have
noticed differences like this and would have asked if it mattered.

Feb 16 1995 05:17:18:930PM Steve Golovato Other run goals -

Go back to D after changeover to H, observe change back.

Puff nitrogen to find suitable lines for tomorrow's run.

Feb 16 1995 09:06:36:920AM 950216001 Steve Golovato Shot 950216001 - early disruption at 0.5 sec.
too much gas early, current rise too slow.
using voltage programming from last shot of yesterday in segment 1.
plenum pressure higher today, cut in voltage programming from
9502015020 and lowered voltage to about 25 volts at abour .1 sec.

Feb 16 1995 12:17:49:120PM 950216001 Steve Golovato Shot 950216001 - disruption also caused because of unannounced
experiment in oh2 supplies. it was removed for shot 2.

Feb 16 1995 09:18:11:410AM 950216002 Steve Golovato Shot 950216002 - fizzle. maybe just because of disruption on first
shot.

Feb 16 1995 09:20:20:990AM 950216003 Steve Golovato Shot 950216003 - plasma. reduced early gas a little more, 35 to 32
volts at about .2 sec for next shot.

Feb 16 1995 09:44:43:100AM 950216004 Steve Golovato Shot 950216004 - moved diversion to around .450 sec by moving ramp
in clearin out by 50 msec. also turned off clearin integral gain,
we'll how it runs and add it back later. childs to setting up rga
for this shot. pcx, tcx, vuv, molymon gate valves opened.

Feb 16 1995 09:52:01:730AM 950216005 Steve Golovato Shot 950216005 - cut M-out into gas voltage programming in segment 2.
it was fairly smooth especially after .5sec so we didn't adjust it
at all, we'll see what we get. turned off nl_04 feedback by reducing
prop gain to zero from flat 8 startgn at .1 sec.

plasma. density very flat, looks like it's feedback controlled,
a little low, nl_04 about 7.3e19.

Feb 16 1995 10:12:06:510AM 950216006 Steve Golovato Shot 950216006 - repeat. plasma. these shots are ramping all the way
down. stays diverted virtually the whole time, the x-point moves in
and the strike points move up the inner wall. this rampdown was
developed presumably by john goets on 950202 since we started with
shot 7 from that day.

Feb 16 1995 10:26:33:500AM 950216007 Steve Golovato Shot 950216007 - changed over to hydrogen. purged a-side plenum
and lines, filled plenum to 20.3#. there was some question whether
to raise or lower prefill with H. I read physop summaries from
950110 and 950203 where 20+% H in D mixtures were run. in both cases
they got fizzles and then lowered the prefill. the prefill was lowered
to 1.2 from 1.5 for this 100% H case. we'll see what happens.

plasma ran, got hards and lower density, nl_04 about 6.e19 and falling
during shot. rga says 50:50 H/D.

Feb 16 1995 10:36:30:250AM 950216008 Steve Golovato Shot 950216008 - raise prefill to 1.3 from 1.2 to reduce hards, also
prevent apparent bounce on inner wall at 14 ms.

plasma, no hards.

Feb 16 1995 10:48:29:440AM 950216009 Steve Golovato Shot 950216009 - gas programming falls off over .5-1.sec. we reduced
the slope of the fall off to see if we can reduce density falloff
with time during shot.

plasma. density went too high, to 8.e19. we'll import segment 2 from
shot 7 and tweak it a little.

Feb 16 1995 11:04:27:970AM 950216010 Steve Golovato Shot 950216010 - density went too high, to 8.e19 in shot 9. we
imported segment 2 from shot 8 (not 7). we had raised the point at
about 640ms from 26.5 to 35.9. this added too much gas too early.
instead this time we added a point at 830 ms and kept gas flat from 640
to 830 ms.

plasma. density pretty flat now. looks good at nl_04=5.7 down
to 5.4e19.

Feb 16 1995 11:14:45:820AM 950216011 Steve Golovato Shot 950216011 - repeat. plasma.

Feb 16 1995 11:34:37:680AM 950216012 Steve Golovato Shot 950216012 - repeat. D fraction falling shot-to-shot.

Feb 16 1995 11:56:44:340AM 950216013 Steve Golovato Shot 950216013 - repeat. D fraction falling shot-to-shot.

plasma. disrupted at 630ms. density has been falling shot-to-shot.
has fallen below 5.e19.where operation is erratic at best even with
feedback. try a shot with feedback at 6.e19 and cut in the voltage
programming for this shot.

Feb 16 1995 12:45:52:770PM 950216013 Steve Golovato Shot 950216013 - the disruption may have been due to ef2u supply.
which went to zero and stayed there from 270ms on.

Feb 16 1995 12:13:59:790PM 950216014 Steve Golovato Shot 950216014 - returned to density feedback at 6.e19.

plasma. cut M-out 14 to gas voltage programming and turned off feedback.
smoothed out the waveform a little.

Feb 16 1995 12:25:58:470PM 950216015 Steve Golovato Shot 950216015 - density feedback off.

plasma. density too high, needs to be tweaked.

Feb 16 1995 12:35:41:250PM 950216016 Steve Golovato Shot 950216016 - reduced peak in gas programming at about 400ms to
40 volts. also reduced some early wiggles.

plasma. density pretty flat but a little low, 5.e19.
session_leader prefers to use feedback to keep it at 6.e19
so we'll do this for next shot.

Feb 16 1995 01:00:49:650PM 950216017 Steve Golovato Shot 950216017 - density feedback on at 6.e19.

plasma. D/H seems to be equilibrating, take one more shot
then do dnesity scan.

Feb 16 1995 01:05:28:650PM 950216018 Steve Golovato Shot 950216018 - repeat.

plasma. last shot of ~constant density shots. start scan of density.
we have shots as low as 5.e19, as high as 8.e19. start scan at
1.e20.

Feb 16 1995 01:09:31:850PM 950216018 Steve Golovato Shot 950216018 - repeat.

plasma. last shot of ~constant density shots. start scan of density.
we have shots as low as 5.e19, as high as 8.e19. start scan at
1.e20 for next shot.

Feb 16 1995 01:31:28:120PM 950216019 Steve Golovato Shot 950216019 - nl_04 set to 1.e20.

plasma. disrupted during rampdown at 1.2 sec., when oh1 reaches current
limit of 20000 at 1 sec. this was inherited from shot that was loaded
(950202007). can be raised to 26000, as it was run yesterday.
done for next shot.

Feb 16 1995 01:41:16:670PM 950216020 Steve Golovato Shot 950216020 - nl_04 set to 1.5e20.

plasma. disrupted early at 400ms. may be excessive gas early
because of increase to 1.5e20. simply raised points at .4 and 1.
sec to 1.5e20. instead, will maintain slope of previous shot
through 1.e20 at 4. to 1.5e20 at .59 sec for next shot.
see if this helps.

Feb 16 1995 01:50:19:100PM 950216021 Steve Golovato Shot 950216021 - nl_04 set to 1.5e20.

plasma. followed programming to the letter, ramping to 1.5e20 at
.6 sec, then flat to disruption just after 1.sec.

Feb 16 1995 02:11:46:020PM 950216021 Steve Golovato Shot 950216021 -
efc oscillation may have led to disruption on last shot.
torvac faulted from overpressure caused by disruption on last shot.

Feb 16 1995 02:16:12:020PM 950216022 Steve Golovato Shot 950216022 - changes to reduce problems during rampdown.
moved zxu down by 2cm from .9 to 1.4 sec.
gain on rxu was off at 1., now of at 1.5 sec.
these changes suggested by horne. they didn't work.

plasma. disrupteds at .9 sec. nl04 flat from 675ms to 890ms at
2.e20.

Feb 16 1995 02:19:19:180PM 950216022 Steve Golovato Shot 950216022 - changes to reduce problems during rampdown.
moved zxu down by 2cm from .9 to 1.4 sec.
gain on rxu was off at 1., now of at 1.5 sec.
these changes suggested by horne. they didn't work.

plasma. disrupteds at .9 sec. nl04 flat from 675ms to 890ms at
2.e20.

chopper gain higher than yesterday, 5 rather than 4. this may lead
to oscillation which prceeds disruption.

rather than continue fighting this, we'll go back to lower density
and switch back to D.

Feb 16 1995 02:37:54:250PM 950216023 Steve Golovato Shot 950216023 - reloading segment 2 of shot 18, feedback controlled
nl at 6.e19.

plasma. returned to previous behavior, ramped all the way down.

Feb 16 1995 02:44:39:770PM 950216024 Steve Golovato Shot 950216024 - reloading segment 2 of shot 11, pre-programmed gas.

plasma. denstiy almost flat at 5.4e19.

Feb 16 1995 02:59:13:540PM 950216025 Steve Golovato Shot 950216025 - gas puff only shot, no magnets. using pre-programmed
puff from last shot. fizzle detector turned off
(on at 1.9sec off at 2.sec)

successful shot, no plasma.

Feb 16 1995 03:24:53:130PM 950216026 Steve Golovato Shot 950216026 - go back to D and reload 950202006 to use the
pre-programmed gas from that shot.

late diversion is leading to heating of antenna protection tiles
early in shot. going back to earlier diversion to avoid this,
moved clearin ramp back to .2 to .25 sec.

a-side plenum pressure 20# D.
b-side-upper plenum pressure 3# nitrogen.

had cell access to open manual valve to nitrogen.

pre-fill back to 1.5e-5 for D.

plasma.

Feb 16 1995 03:39:02:890PM 950216027 Steve Golovato Shot 950216027 - repeat but add 20ms nitrogen puff from b-side-upper
at .5 sec.

plasma. earlier diversion eliminates glowing on antenna tiles.
density ramping up, from 7.e19 at .5 to 9.5e19 at 1. sec.
going back to feedback at 8.e19. effects of nitrogen puff seen.

Feb 16 1995 04:07:06:680PM 950216029 Steve Golovato Shot 950216029 - repeat. garry is looking for various nitrogen lines
shot-to-shot with the oma as we also observe change back to D.
as of last shot, the rga says 50:50.

plasma. nitrogen barely visible on last 2 shots, big effect on shot
27 was due to a simultaeous, spontaneous, humongous moly injection.

Feb 16 1995 04:29:48:650PM 950216030 Steve Golovato Shot 950216030 - lengthed nitrogen puff to 40ms at 5. sec.

plasma. nitrogen puff clear on 2pi for example. FSP was firing
at .5sec causing coincident moly injection. it was turned off for
this shot.

Feb 16 1995 04:35:46:950PM 950216031 Steve Golovato Shot 950216031 - repeat.

plasma.

Feb 16 1995 04:36:43:500PM 950216031 Steve Golovato Shot 950216031 - repeat.

plasma.

Feb 16 1995 04:47:43:680PM 950216032 Steve Golovato Shot 950216032 - nitrogen puff to 60ms at .5 sec.

plasma.

Feb 16 1995 05:00:57:590PM 950216033 Steve Golovato Shot 950216033 - reload shot 26, first shot in D after H shots.
uses pre-programmed gas puff, no feedback.
added 60ms nitrogen puff at .5 sec.

plasma.

Feb 16 1995 05:14:14:150PM 950216034 Steve Golovato Shot 950216034 - last shot gas puff only, no magnets.
using puff from shot 33. fizzle detector disabled.

successful puff.

Engineering Operator Comments

Shot Time Type Status Comment

1 08:42:20:380AM Plasma Ok Comm fault OH2 L

2 09:00:58:330AM Plasma Ok No Faults

3 09:10:16:860AM Plasma Ok No Faults

4 09:32:15:040AM Plasma Ok No Faults.

5 09:47:22:190AM Plasma Ok No Faults

6 09:58:11:300AM Plasma Ok No Faults.

7 10:14:18:260AM Plasma Ok No Faults.

8 10:29:29:020AM Plasma Ok No Faults.

9 10:44:05:550AM Plasma Ok No Faults.

10 10:58:29:990AM Plasma Ok No Faults

11 11:12:35:260AM Plasma Ok No Faults.

12 11:28:33:420AM Plasma Ok no faults

13 11:43:19:500AM Plasma Ok comm fail oh2u

14 12:02:08:170PM Plasma Ok no faults

15 12:16:16:190PM Plasma Ok no faults

16 12:30:21:630PM Plasma Ok no faults

17 12:47:03:690PM Plasma Ok no faults

18 01:01:14:610PM Plasma Ok no faults

19 01:16:36:050PM Plasma Ok Comm Fault EF1U, OH1,& OH2U

20 01:32:14:290PM Plasma Ok No Faults.

21 01:46:41:710PM Plasma Ok Comm Faults, ef1u, OH2U&L, OH1. First fault OH2U.

22 02:10:58:950PM Plasma Bad Comm Fail OH2L OH1

23 02:25:11:980PM Plasma Ok No Faults.

24 02:40:22:770PM Plasma Ok No Faults.

25 02:54:01:050PM Test Ok Gas Fill Test. Power supplies off.

26 03:18:27:840PM Plasma Ok No Faults.

27 03:31:40:520PM Plasma Ok No Faults.

28 03:45:06:020PM Plasma Ok No Faults.

29 04:01:31:090PM Plasma Ok No Faults.

30 04:16:08:290PM Plasma Ok No Faults.

31 04:31:04:490PM Plasma Ok No Faults.

32 04:44:48:510PM Plasma Ok No Faults.

33 04:59:09:810PM Plasma Ok No Faults

34 05:13:04:860PM Test Ok Gas nPuff Test., power system off.

Session Leader Comments
Feb 16 1995 08:35:05:120AM		Gary McCracken	Isotope Exchange experiment EO F Silva PO S Golovato SL G McCracken MP 082 Purpose:1. To measure the evolution of the isotopic composition in the plasma both during a discharge and from shot to shot when the fuelling is changed from deuterium to hydrogen and back again. 2. To compare the Mo sputter rate in hydrogen and deuterium The main diagnostics for the isotope exchange experiment are the charge exchange detector, the oma spectrometer looking at Halpha, and the Dycor RGA looking at the gas released after the shot
Feb 16 1995 05:37:14:290PM		Gary McCracken	Summary: Very successful day. 31 plasmas. All 3 diagnostics for the H/D ratio worked well and appear on first sight to be fairly consistent. The D to H changeover to deuterium was done for 12 shots after which the D/H+D ratio had dropped from about 97% to 20% as measured on the RGA. Data from the oma is still to be analysed. We then did a density scan from 0.6 to 2e20 in H by which time the D/H+D had dropped to 0.15. The change back to D lasted 8 shots, by which time the D/H+D da risen back to 0.76. We also did some preliminary N2 puffing to identify lines for tomorrow. Li like N was seen on the Mcpherson and a NII line on the oma. The injected gas disappears in less than 100 ms
Feb 16 1995 09:01:48:970AM	950216001	Gary McCracken	Disruption at 0.5 s. Apparently a problem with the gas puff during the pulse. Note: the plenum pressure for the D2 fill is 20.3 psi
Feb 16 1995 09:06:33:420AM	950216002	Gary McCracken	Fizzle
Feb 16 1995 09:31:31:180AM	950216003	Gary McCracken	Good shot. Nice Halpha data from the oma. No data from CX as the valve was not opened. No data from the rga yet. nel04=8e19 , good. However density is still on feedback and we want it to be preprogrammed so that we put in a well defined amount of gas We want to divert a little later so that we reach full current while still limited in the next shot. Also
Feb 16 1995 09:47:00:000AM	950216004	Gary McCracken	Good shot. nel04=7.9e19. but still feedback. Cx data looks good. RGA taking data; transferred successfully to the vax and available on the scope. Not fully diverted until 0.5 s, which is fine
Feb 16 1995 09:57:31:080AM	950216005	Gary McCracken	Good shot. nel04=7.1e19.Now preprogrammed. Looks good although a little lower density. All data looks good
Feb 16 1995 10:13:26:550AM	950216006	Gary McCracken	Good shot. No density trace. Otherwise fine. Took FSP scan this shot Change to all hydrogen feed for the next shot.
Feb 16 1995 10:32:54:160AM	950216007	Gary McCracken	First shot with all hydrogen fill. Gas fill reduced to get breakdown Hard x-rays. nel05= 5.8e19, falling during the pulse to 4.5e19 The H/D ratio is about 1:1 on the RGA after the shot and also on the oma CX indicates the the H/D ratio falls from 80% to 40% during the shot. Try to raise density in the next shot
Feb 16 1995 10:45:34:400AM	950216008	Gary McCracken	Good shot. Second in H2 . Density still low, 5.7e19. H/D ratio about 2:1 on RGA. Increase gas fill slightly in next shot to keep density constant
Feb 16 1995 11:01:24:120AM	950216009	Gary McCracken	Good shot. Third in H2 . Overdid the extra gas puff. Density went up , 8.2e19e19. Data look fine
Feb 16 1995 11:09:19:510AM	950216009	Gary McCracken	RGA H/D ratio 1.5 to 0.4
Feb 16 1995 11:17:52:680AM	950216010	Gary McCracken	Good shot. 4th in H2. Density fairly flat at 5.7e Good data. % of D/(H+D) now available on RGA scope. Starts at 40%, dips to 25% and then rises again to nearly 40% after 10 mins
Feb 16 1995 11:38:19:660AM	950216011	Gary McCracken	Good shot. 5th in H2. Density fairly flat at 5.4e19 Good data. D/(H+D) Starts at 38%, dips to 22% and then rises again to nearly 37% after 10 mins
Feb 16 1995 11:44:11:240AM	950216012	Gary McCracken	Good shot. 6th in H2. Density fairly flat at 5.4e19 Good data. D/(H+D) =32% after 10 mins
Feb 16 1995 12:00:14:850PM	950216013	Gary McCracken	7th in H2. Disruption at 0.6 s. Maybe the density is falling too low We will use density feedback at 6e19 for the next shot hopefully to get out of trouble. D/(H+D) =30% after 10 mins
Feb 16 1995 12:16:40:510PM	950216014	Gary McCracken	8th in H2. Good shot again. Have set density feedback.nel04=6e19 We will use the feedback signals to preprogram for the next shot D/(H+D) =25% after 10 mins
Feb 16 1995 12:35:32:740PM	950216015	Gary McCracken	9th in H2. Good shot .nel04=7.7e19 preprogrammed density. too high Try to reduce it in next shot D/(H+D) = 23 % after 10 mins. Not much change from shot to shot.
Feb 16 1995 12:52:36:660PM	950216016	Gary McCracken	10th in H2. Good shot . nel04=4.7e19 too low D/(H+D) = 23 % after 10 mins. No change from last shot.
Feb 16 1995 01:01:19:090PM	950216017	Gary McCracken	11th in H2. Good shot .Back to feedback control of density nel04=6.3e19 D/(H+D) = 22 % after 10 mins. No change from last shot.
Feb 16 1995 01:15:52:700PM	950216018	Gary McCracken	12th in H2. Good shot .Feedback control of density nel04=6.0e19 Change oma to lamda=3900 to look at MoI. Lovely spectra at about 0.4 s D/(H+D) = 21 % after 10 mins. About 1% change from shot to shot.
Feb 16 1995 01:30:58:280PM	950216019	Gary McCracken	13th in H2. Good shot .Feedback control of density. Start of density scan, nel04=1.0e20 disruption in the rampdown. oma lamda=3900; good MoI. spectra RGA D/(H+D) = 20 % after 10 mins. .
Feb 16 1995 01:45:52:050PM	950216020	Gary McCracken	14th in H2. Plan to go to 1.5e20 Disrupts at 0.4 s. Too much gas? RGA D/(H+D) = 18 % after 10 mins. .
Feb 16 1995 02:06:42:520PM	950216021	Gary McCracken	15th in H2. Achieved 1.5e20 this time Disrupted at 1 s. MoI data early (~0.3 s) on oma but large high n H Balmer lines later, ~0.36 s RGA D/(H+D) = 17 % after 10 mins. .
Feb 16 1995 02:24:55:170PM	950216022	Gary McCracken	16th in H2. reached 2e20 at o.7 s Disrupted at 0.9 s. MoI data early (~0.3 s) on oma RGA D/(H+D) = 15 % after 10 mins. .
Feb 16 1995 02:38:53:220PM	950216023	Gary McCracken	17th in H2. End of density scan. Return to low density nel04=0.6e20 with feedback. Large Mo peaks at 0.45 s RGA D/(H+D) = 15 % after 10 mins. .
Feb 16 1995 02:56:39:730PM	950216024	Gary McCracken	18th in H2. Preprogrammed density as in shot 11. nel04=0.54e20 . oma back on Halpha. good data RGA D/(H+D) = 16 % after 10 mins. . Next shot will be a gas calibration shot with no plasma. Fizzle detector off
Feb 16 1995 03:03:43:240PM	950216025	Gary McCracken	Gas calibration shot. No plasma. Fizzle detector off Good data on the ratiomatic also on the RGA
Feb 16 1995 03:25:56:090PM	950216026	Gary McCracken	First shot back with deuterium as the fill gas. Try to repeat shot 006, the last shot we had in D2 with preprogram gas fill. Good shot. Density nel04 about 8e19 , although rising a bit through the pulse
Feb 16 1995 03:49:03:770PM	950216027	Gary McCracken	Second shot back with deuterium as the fill gas. preprogram gas fill. Good shot. Density nel04 about 8e19 , First Nitrogen injection through Bside upper.Plenum pressure 3 psi, Pulse length 20ms at 0.5 s.Plan to have line identification on the oma and the McPherson. The N2 clearly affected the radiation and cooled the plasma. Seen as lithium like nitrogen on the Mcpherson. It drops to nearly zero in 100 ms indicating that it is non recycling. The oma was 400 nm to try and see the NII line at 399.5 nm. It was barely visibleat
Feb 16 1995 04:05:47:920PM	950216028	Gary McCracken	Third shot back with deuterium as the fill gas. Density feedback. Good shot. Density nel04 about 8.2e19 , D/H+D =0.6 and is fairly constant . Last shot it was 0.5 s Nominally the same N2 puff. However the effect is much less globally and in the spectra N2 puff; oma at 460 nm to see NII at 463 nm. Small peak at 0.5 s falling in 100 ms. The previous global effect in shot 27 may be due to moly rather than N2
Feb 16 1995 04:18:13:910PM	950216029	Gary McCracken	Fourth shot back with deuterium as the fill gas. Density feedback. Good shot. Density nel04 about 8.2e19 , D/H+D =0.63 and is fairly constant . Nominally the same N2 puff. oma at 345nm to look for NIV lines. There is a reasonable peak.
Feb 16 1995 04:30:11:500PM	950216030	Gary McCracken	5th shot back with deuterium as the fill gas. Density feedback. Good shot. Density nel04 about 8.2e19 , D/H+D =0.67 and is fairly constant . N2 puff.increased to 40 ms. Still 100 V 3.2psi plenum pressure oma lamda at 3930 to look at NII again at 3995. A clear peak is seen at o.5 s, about 150 counts high.
Feb 16 1995 04:45:08:930PM	950216031	Gary McCracken	6th shot back with deuterium as the fill gas. Density feedback. Good shot. Density nel04 about 8.2e19 , D/H+D =0.71 N2 puff still 40 ms. 100 V 3.2psi plenum pressure oma lamda at 6560 to look at Halpha good data
Feb 16 1995 04:59:16:260PM	950216032	Gary McCracken	7th shot back with deuterium as the fill gas. Density feedback. Good shot. Density nel04 about 8.2e19 , D/H+D =0.74 N2 puff still 60 ms. 100 V 3.2psi plenum pressure oma lamda at 6560 to look at Halpha good data
Feb 16 1995 05:13:00:600PM	950216033	Gary McCracken	8th shot back with deuterium as the fill gas. Density preprogrammed as for shot 026 Good shot. Density nel04 about 8.8e19 but rising during shot , RGA D/H+D =0.76 N2 puff still 60 ms. 100 V 3.2psi plenum pressure oma lamda at 6560 to look at Halpha good data
Feb 16 1995 05:20:16:030PM	950216034	Gary McCracken	Gas calibration shot only. No plasma. D2 preprogrammed as for shot 033 Data taken with the ratiomatic and with the RGA

Physics Operator Comments
Feb 16 1995 09:04:01:580AM		Steve Golovato	Goals of run 950216 Start in deuterium. Get shot with nl_04=8.e19, diverting about 0.4 sec. Remove density feedback (cut M-out signal into voltage programming). Once conditions established, change to hydrogen and observe changeover over a number of shots. After this, do density scan to study H sputtering of Mo. Starting with shot 950202007 which had strike point at FMP2, as desired by the session_leader. Changes to this shot were: (1) nl_04 programming changed from 9.e19 to 8.e19. (2) diversion moved to .4 sec from .2 sec by moving clearin ramp from by this amount of time. (3) moved clearin integral gain turn on to .5 sec from .3 sec (4) changed fill to 1.5 from 1.7e-5. a-side plenum pressure 20.3#.
Feb 16 1995 03:55:56:670PM		Steve Golovato	Note: engineering copied in conditions of shot 950202007, as requested. This shot had ef2 start time of -.4 sec. we now run -.5 sec. This turned out not to be a problem but care should be taken by phyics and engineering operators when fairly old shots are loaded as many conditions evolve with time. If I had compared the engineering data sheet given me this morning with one from yesterday, I might have noticed differences like this and would have asked if it mattered.
Feb 16 1995 05:17:18:930PM		Steve Golovato	Other run goals - Go back to D after changeover to H, observe change back. Puff nitrogen to find suitable lines for tomorrow's run.
Feb 16 1995 09:06:36:920AM	950216001	Steve Golovato	Shot 950216001 - early disruption at 0.5 sec. too much gas early, current rise too slow. using voltage programming from last shot of yesterday in segment 1. plenum pressure higher today, cut in voltage programming from 9502015020 and lowered voltage to about 25 volts at abour .1 sec.
Feb 16 1995 12:17:49:120PM	950216001	Steve Golovato	Shot 950216001 - disruption also caused because of unannounced experiment in oh2 supplies. it was removed for shot 2.
Feb 16 1995 09:18:11:410AM	950216002	Steve Golovato	Shot 950216002 - fizzle. maybe just because of disruption on first shot.
Feb 16 1995 09:20:20:990AM	950216003	Steve Golovato	Shot 950216003 - plasma. reduced early gas a little more, 35 to 32 volts at about .2 sec for next shot.
Feb 16 1995 09:44:43:100AM	950216004	Steve Golovato	Shot 950216004 - moved diversion to around .450 sec by moving ramp in clearin out by 50 msec. also turned off clearin integral gain, we'll how it runs and add it back later. childs to setting up rga for this shot. pcx, tcx, vuv, molymon gate valves opened.
Feb 16 1995 09:52:01:730AM	950216005	Steve Golovato	Shot 950216005 - cut M-out into gas voltage programming in segment 2. it was fairly smooth especially after .5sec so we didn't adjust it at all, we'll see what we get. turned off nl_04 feedback by reducing prop gain to zero from flat 8 startgn at .1 sec. plasma. density very flat, looks like it's feedback controlled, a little low, nl_04 about 7.3e19.
Feb 16 1995 10:12:06:510AM	950216006	Steve Golovato	Shot 950216006 - repeat. plasma. these shots are ramping all the way down. stays diverted virtually the whole time, the x-point moves in and the strike points move up the inner wall. this rampdown was developed presumably by john goets on 950202 since we started with shot 7 from that day.
Feb 16 1995 10:26:33:500AM	950216007	Steve Golovato	Shot 950216007 - changed over to hydrogen. purged a-side plenum and lines, filled plenum to 20.3#. there was some question whether to raise or lower prefill with H. I read physop summaries from 950110 and 950203 where 20+% H in D mixtures were run. in both cases they got fizzles and then lowered the prefill. the prefill was lowered to 1.2 from 1.5 for this 100% H case. we'll see what happens. plasma ran, got hards and lower density, nl_04 about 6.e19 and falling during shot. rga says 50:50 H/D.
Feb 16 1995 10:36:30:250AM	950216008	Steve Golovato	Shot 950216008 - raise prefill to 1.3 from 1.2 to reduce hards, also prevent apparent bounce on inner wall at 14 ms. plasma, no hards.
Feb 16 1995 10:48:29:440AM	950216009	Steve Golovato	Shot 950216009 - gas programming falls off over .5-1.sec. we reduced the slope of the fall off to see if we can reduce density falloff with time during shot. plasma. density went too high, to 8.e19. we'll import segment 2 from shot 7 and tweak it a little.
Feb 16 1995 11:04:27:970AM	950216010	Steve Golovato	Shot 950216010 - density went too high, to 8.e19 in shot 9. we imported segment 2 from shot 8 (not 7). we had raised the point at about 640ms from 26.5 to 35.9. this added too much gas too early. instead this time we added a point at 830 ms and kept gas flat from 640 to 830 ms. plasma. density pretty flat now. looks good at nl_04=5.7 down to 5.4e19.
Feb 16 1995 11:14:45:820AM	950216011	Steve Golovato	Shot 950216011 - repeat. plasma.
Feb 16 1995 11:34:37:680AM	950216012	Steve Golovato	Shot 950216012 - repeat. D fraction falling shot-to-shot.
Feb 16 1995 11:56:44:340AM	950216013	Steve Golovato	Shot 950216013 - repeat. D fraction falling shot-to-shot. plasma. disrupted at 630ms. density has been falling shot-to-shot. has fallen below 5.e19.where operation is erratic at best even with feedback. try a shot with feedback at 6.e19 and cut in the voltage programming for this shot.
Feb 16 1995 12:45:52:770PM	950216013	Steve Golovato	Shot 950216013 - the disruption may have been due to ef2u supply. which went to zero and stayed there from 270ms on.
Feb 16 1995 12:13:59:790PM	950216014	Steve Golovato	Shot 950216014 - returned to density feedback at 6.e19. plasma. cut M-out 14 to gas voltage programming and turned off feedback. smoothed out the waveform a little.
Feb 16 1995 12:25:58:470PM	950216015	Steve Golovato	Shot 950216015 - density feedback off. plasma. density too high, needs to be tweaked.
Feb 16 1995 12:35:41:250PM	950216016	Steve Golovato	Shot 950216016 - reduced peak in gas programming at about 400ms to 40 volts. also reduced some early wiggles. plasma. density pretty flat but a little low, 5.e19. session_leader prefers to use feedback to keep it at 6.e19 so we'll do this for next shot.
Feb 16 1995 01:00:49:650PM	950216017	Steve Golovato	Shot 950216017 - density feedback on at 6.e19. plasma. D/H seems to be equilibrating, take one more shot then do dnesity scan.
Feb 16 1995 01:05:28:650PM	950216018	Steve Golovato	Shot 950216018 - repeat. plasma. last shot of ~constant density shots. start scan of density. we have shots as low as 5.e19, as high as 8.e19. start scan at 1.e20.
Feb 16 1995 01:09:31:850PM	950216018	Steve Golovato	Shot 950216018 - repeat. plasma. last shot of ~constant density shots. start scan of density. we have shots as low as 5.e19, as high as 8.e19. start scan at 1.e20 for next shot.
Feb 16 1995 01:31:28:120PM	950216019	Steve Golovato	Shot 950216019 - nl_04 set to 1.e20. plasma. disrupted during rampdown at 1.2 sec., when oh1 reaches current limit of 20000 at 1 sec. this was inherited from shot that was loaded (950202007). can be raised to 26000, as it was run yesterday. done for next shot.
Feb 16 1995 01:41:16:670PM	950216020	Steve Golovato	Shot 950216020 - nl_04 set to 1.5e20. plasma. disrupted early at 400ms. may be excessive gas early because of increase to 1.5e20. simply raised points at .4 and 1. sec to 1.5e20. instead, will maintain slope of previous shot through 1.e20 at 4. to 1.5e20 at .59 sec for next shot. see if this helps.
Feb 16 1995 01:50:19:100PM	950216021	Steve Golovato	Shot 950216021 - nl_04 set to 1.5e20. plasma. followed programming to the letter, ramping to 1.5e20 at .6 sec, then flat to disruption just after 1.sec.
Feb 16 1995 02:11:46:020PM	950216021	Steve Golovato	Shot 950216021 - efc oscillation may have led to disruption on last shot. torvac faulted from overpressure caused by disruption on last shot.
Feb 16 1995 02:16:12:020PM	950216022	Steve Golovato	Shot 950216022 - changes to reduce problems during rampdown. moved zxu down by 2cm from .9 to 1.4 sec. gain on rxu was off at 1., now of at 1.5 sec. these changes suggested by horne. they didn't work. plasma. disrupteds at .9 sec. nl04 flat from 675ms to 890ms at 2.e20.
Feb 16 1995 02:19:19:180PM	950216022	Steve Golovato	Shot 950216022 - changes to reduce problems during rampdown. moved zxu down by 2cm from .9 to 1.4 sec. gain on rxu was off at 1., now of at 1.5 sec. these changes suggested by horne. they didn't work. plasma. disrupteds at .9 sec. nl04 flat from 675ms to 890ms at 2.e20. chopper gain higher than yesterday, 5 rather than 4. this may lead to oscillation which prceeds disruption. rather than continue fighting this, we'll go back to lower density and switch back to D.
Feb 16 1995 02:37:54:250PM	950216023	Steve Golovato	Shot 950216023 - reloading segment 2 of shot 18, feedback controlled nl at 6.e19. plasma. returned to previous behavior, ramped all the way down.
Feb 16 1995 02:44:39:770PM	950216024	Steve Golovato	Shot 950216024 - reloading segment 2 of shot 11, pre-programmed gas. plasma. denstiy almost flat at 5.4e19.
Feb 16 1995 02:59:13:540PM	950216025	Steve Golovato	Shot 950216025 - gas puff only shot, no magnets. using pre-programmed puff from last shot. fizzle detector turned off (on at 1.9sec off at 2.sec) successful shot, no plasma.
Feb 16 1995 03:24:53:130PM	950216026	Steve Golovato	Shot 950216026 - go back to D and reload 950202006 to use the pre-programmed gas from that shot. late diversion is leading to heating of antenna protection tiles early in shot. going back to earlier diversion to avoid this, moved clearin ramp back to .2 to .25 sec. a-side plenum pressure 20# D. b-side-upper plenum pressure 3# nitrogen. had cell access to open manual valve to nitrogen. pre-fill back to 1.5e-5 for D. plasma.
Feb 16 1995 03:39:02:890PM	950216027	Steve Golovato	Shot 950216027 - repeat but add 20ms nitrogen puff from b-side-upper at .5 sec. plasma. earlier diversion eliminates glowing on antenna tiles. density ramping up, from 7.e19 at .5 to 9.5e19 at 1. sec. going back to feedback at 8.e19. effects of nitrogen puff seen.
Feb 16 1995 04:07:06:680PM	950216029	Steve Golovato	Shot 950216029 - repeat. garry is looking for various nitrogen lines shot-to-shot with the oma as we also observe change back to D. as of last shot, the rga says 50:50. plasma. nitrogen barely visible on last 2 shots, big effect on shot 27 was due to a simultaeous, spontaneous, humongous moly injection.
Feb 16 1995 04:29:48:650PM	950216030	Steve Golovato	Shot 950216030 - lengthed nitrogen puff to 40ms at 5. sec. plasma. nitrogen puff clear on 2pi for example. FSP was firing at .5sec causing coincident moly injection. it was turned off for this shot.
Feb 16 1995 04:35:46:950PM	950216031	Steve Golovato	Shot 950216031 - repeat. plasma.
Feb 16 1995 04:36:43:500PM	950216031	Steve Golovato	Shot 950216031 - repeat. plasma.
Feb 16 1995 04:47:43:680PM	950216032	Steve Golovato	Shot 950216032 - nitrogen puff to 60ms at .5 sec. plasma.
Feb 16 1995 05:00:57:590PM	950216033	Steve Golovato	Shot 950216033 - reload shot 26, first shot in D after H shots. uses pre-programmed gas puff, no feedback. added 60ms nitrogen puff at .5 sec. plasma.
Feb 16 1995 05:14:14:150PM	950216034	Steve Golovato	Shot 950216034 - last shot gas puff only, no magnets. using puff from shot 33. fizzle detector disabled. successful puff.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:42:20:380AM	Plasma	Ok	Comm fault OH2 L
2	09:00:58:330AM	Plasma	Ok	No Faults
3	09:10:16:860AM	Plasma	Ok	No Faults
4	09:32:15:040AM	Plasma	Ok	No Faults.
5	09:47:22:190AM	Plasma	Ok	No Faults
6	09:58:11:300AM	Plasma	Ok	No Faults.
7	10:14:18:260AM	Plasma	Ok	No Faults.
8	10:29:29:020AM	Plasma	Ok	No Faults.
9	10:44:05:550AM	Plasma	Ok	No Faults.
10	10:58:29:990AM	Plasma	Ok	No Faults
11	11:12:35:260AM	Plasma	Ok	No Faults.
12	11:28:33:420AM	Plasma	Ok	no faults
13	11:43:19:500AM	Plasma	Ok	comm fail oh2u
14	12:02:08:170PM	Plasma	Ok	no faults
15	12:16:16:190PM	Plasma	Ok	no faults
16	12:30:21:630PM	Plasma	Ok	no faults
17	12:47:03:690PM	Plasma	Ok	no faults
18	01:01:14:610PM	Plasma	Ok	no faults
19	01:16:36:050PM	Plasma	Ok	Comm Fault EF1U, OH1,& OH2U
20	01:32:14:290PM	Plasma	Ok	No Faults.
21	01:46:41:710PM	Plasma	Ok	Comm Faults, ef1u, OH2U&L, OH1. First fault OH2U.
22	02:10:58:950PM	Plasma	Bad	Comm Fail OH2L OH1
23	02:25:11:980PM	Plasma	Ok	No Faults.
24	02:40:22:770PM	Plasma	Ok	No Faults.
25	02:54:01:050PM	Test	Ok	Gas Fill Test. Power supplies off.
26	03:18:27:840PM	Plasma	Ok	No Faults.
27	03:31:40:520PM	Plasma	Ok	No Faults.
28	03:45:06:020PM	Plasma	Ok	No Faults.
29	04:01:31:090PM	Plasma	Ok	No Faults.
30	04:16:08:290PM	Plasma	Ok	No Faults.
31	04:31:04:490PM	Plasma	Ok	No Faults.
32	04:44:48:510PM	Plasma	Ok	No Faults.
33	04:59:09:810PM	Plasma	Ok	No Faults
34	05:13:04:860PM	Test	Ok	Gas nPuff Test., power system off.