Alcator C-Mod Run 950505 Information

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Miniproposals
Miniproposal:093
Date Filed: 3/1/1995
Title:ICRF H-Mode Density Scan with Reversed Toroidal Field
First Author:Joseph Snipes
Session Leader:Steve Golovato (shots 1-29)

Operators
Session leader(s):Steve Golovato
Physics operator(s):Joseph Snipes
Engineering operator(s):Vinny Bertolino,Joe Daigle

Engineering Operator Run Comment
snipe/hmode

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:13:663PM
Author: To Be Determined
run summary - 950505
---------------------
SL: golovato
PO: snipes
EO: bertolino/daigle

This run was moderately successful. We got many "good" h-modes but
they were brief (40-70ms) and had modest h-factors (1.3-1.4).
"Good" h-modes are defined here to mean elm-free and with a sharp
density rise (much improved particle confinement). The main problem
with obtaining good h-modes with icrf is that low thresholds imply low
density and large outer gaps, both of which lower loading and lower
power for a given voltage limit. When we enter the h-mode loading
drops further and the density (and threshold) rise sharply. The upshot
of this is that the best icrf h-modes occur with higher starting
densities where we can put in more power, but the sharp density rise
appears to keep us always near the threshold such that, at best we
oscillate back and forth between elm-free and elmy phases.

We started at 800ka and nl04=0.8-0.9e20 just before the rf and got elmy
h-modes at just under 2 MW. By raising the initial density to 1.1e20,
we began to get short elm-free phases. Since the drop in loading in h-mode
required us to lower the power during h-mode to avoid trips (even though
we increased our maximum voltage trip point all day), we tried playing
around with moving the plasma toward the antenna as we entered
h-mode (feed-forward rather than feedback control of the outer gap)
but had no great success. We did not exhaust the possibilities here
and it could be worth trying this some more, maybe with feedback.
We then went to 1MA and tried to raise the initial density. It turned
out that the a-side valve was flat out, so we did several things to
get the density up; raising the plenum pressure, adding more preprogrmmed
gas, moving the rf later in time, and puffing from b-side upper as well
as a-side. We raised the initial density to 1.3e20 and the initial
power to 2.7MW (this through higher loading and higher voltage trip limit)
and got three got oscillations from elm-free to elmy to elm-free...
It appeared that the drop in power coupled with the density increase in
the elm-free phase caused a reversion to an elmy phase (or l-mode) where
the density decreased. This process repeated itself 2-3 times on many shots.

We tried 1.2MA and got an h-mode on one shot, but after getting late
disruptions on each shot chickened out of running at such high currents
and went to low current (600kA) where the l-mode confinement is worse,
hoping to see bigger h-factors. We also lowered the initial density
at the lower current and got continuous elmy h-modes.

There appeared to be sharp increases in moly as well as density in the
elm-free h-modes. Jim Terry tried several laser blowoffs to
measure the impurity transport. Brian got several FSP scans during
elm-free phases. It is not clear what we can do to get long
elm-free h-modes. It seems the loading problem is forcing us to track
the threshold and never get much above it with the power we have
available. The high moly levels may be playing a role in the low
h-factors. We have almost 3 weeks to the next h-mode run, enough
time to plot some new strategies.

The session leader shot-to-shot summary can be found in the logbook under the
session_leader topic. Details on technical difficulties can be found in the
physics operator summary.

The shot summary was: 25 plasmas (only one disrupted too early to use)
4 fizzles


Physics Operator Summaries
Entered: Jul 7 2004 04:36:54:147PM
Author: To Be Determined
ICRF H-mode Run
Engineer in Charge: Vinny Bertolino
Physics Operator: Joseph Snipes
Session Leader: Steve Golovato

Copied shot 950504018 with reduced pre-programmed density. Plan is to try
to increase the H-mode H factors with high power ICRF. The plasma current
was scanned up to 1.2 MA and down to 0.6 MA. There were 23 H-mode shots
today at each of the three plasma currents. The ELM-free H-modes lasted up
to 60 msec with H factors up to about 1.35. We had a very good run and the
machine ran very well. The difficulties of getting high H factor long
duration ICRF H-modes are that the RF couples well only at high density,
but the H-mode threshold increases with density, so more power is required
to maintain the H-mode. The density rises in ELM-free H-mode are not well
controlled and soon the RF power is insufficient to remain in H-mode. The
highest RF power achieved today was about 2.5 MW. Perhaps, one indication
from this run is that smaller outer gaps may not be so bad for H-modes as
previously thought in that we ran outer gaps down to 1.2 cm and still
achieved fairly good H-modes. So, it may be possible to run even smaller
outer gaps to improve the RF coupling and increase the input power to
improve the H-modes. The Fast Scanning Probe was inserted into several
H-mode shots, so there should be some good edge H-mode data from this run.

Run statistics: 29 shots, 27 plasmas, 2 fizzles

Shot 1
Pre fill set to 2.0 x 10^-5 Torr. nl04 set to 7 x 10^19 m^-2.
Reached 300 kA, but then disrupted. EFC fault that occurs after the plasma
disappears!? Lots of hard x rays.

Shot 2
Returned nel to 1.38 x 10^20 m^-2 as in shot 950504018. RF should be on
for this shot. Disrupted at 0.5 sec. Density rise too rapid. Reduced the
rate of rise of the density for shot 3.

Shot 3
Good shot. ICRF H-mode from 0.65 - 0.92 sec.

Shot 4
Reduced density to 1.1 x 10^20 m^-2. Good shot. ELMy ICRF H-mode from 0.65
to 0.9 sec.

Shot 5
Put a step in the RCUR of 3 mm from 0.5 to 0.8 sec to decrease the outer
gap while the density rises. ELMy RF H-mode 0.65 to almost 1 sec.

Shot 6
Raised density to 1.3 x 10^20 at 0.6 sec, maintaining the rate of rise of
the density before 0.5 sec to avoid disruptions. Then, lowered the density
to 1.2 x 10^20 m^-2 after 0.75 sec. Good shot. ELM-free RF H-mode 0.7 -
0.75 s.

Shot 7
Took out the step in RCUR. Moved ZXL down by 1 cm from 0.55 to 1.2 sec.
Good shot. ELM-free ICRF H-mode from 0.69 - 0.74 sec.

Shot 8
Decreased RXL by 5 mm during the flattop. Good shot. ELM-free ICRF H-mode
from 0.69 - 0.73 sec.

Shot 8
Decreased RXL by 5 mm during the flattop. Good shot. ELM-free ICRF H-mode
from 0.69 - 0.73 sec, then ELMy until 0.9 sec.

Shot 9
Repeat with FSP at 0.7 and 0.95 sec. Disrupted at 0.88 sec. Moly level
rises dramatically during RF. ELM-free RF H-mode from 0.69 - 0.73 sec,
then ELMy until 0.8 sec.

Shot 10
Stepped out RCUR by 3 mm from 0.65 to 1.0 sec. Enabled Ar puff. Disrupted
at 0.55 sec. Too much Ar. Reduced puff by a factor of two in duration for
shot 11.

Shot 10
Stepped out RCUR by 3 mm from 0.65 to 1.0 sec. Enabled Ar puff. Disrupted
at 0.55 sec. Too much Ar. Reduced puff by a factor of two in duration for
shot 11. Correction. John was just feeling guilty. It was a large moly
injection that caused the disruption.

Shot 11
Repeat with shorter Ar puff. ELM-free RF H-mode from 0.69 to 0.73 sec,
then ELMy until 0.92 sec.

Shot 12
Longer Ar puff (28 ms). Ip raised to 1.0 MA. Disrupted at 1.15 sec. RF D
port antenna failed, so there was only 0.5 MW of RF power. No H-mode.

Shot 13
Repeat. Good shot. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy
until 1.09 sec.

Shot 14
Raised programmed nel to 1.5 x 10^20 m^-2 hoping to get 1.4. Disrupted at
0.96 sec. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy until the
disruption. Moly injection at 0.9 sec led to the disruption.

Shot 15
Raised pre-programmed gas from 0.25 to 0.6 sec to try to increase the
density. Two RF H-modes from 0.69 - 0.73 and 0.81 - 0.86 sec. H factor
1.25.

Shot 16
Moved RF time to 0.7 sec. Good shot. Several RF H-modes from 0.72 to 0.92
sec.

Shot 17
Tweaked density to try to increase it a bit. Good shot. RF H-modes from
0.72 to 0.91 sec.

Shot 18
Repeat with A side plenum set to 20 psi. RF moved back to 0.75 sec. Good
shot. RF H-mode from 0.85 to 0.95 sec. H factor of 1.2.

Shot 19
Added B side upper gas valve to get more density. Set to 31 V from 0.3 to
0.75 sec. Good shot. ELM-free RF H-modes from 0.85 - 0.91 sec and 0.95 to
1.02 sec.

Shot 20
Repeat. Good shot. ELM-free RF H-modes from 0.78 - 0.83 and 0.87 - 0.92
sec.

Shot 21
Repeat with Sc injection at 0.775 sec. Good shot. 3 RF H-modes from 0.78
- 0.83, 0.87 - 0.9, and 0.92 - 0.95 sec. H factor of 1.35.

Shot 22
Repeat with Sc injection at 775 msec. Good shot. 3 RF H-modes 0.77 -
0.83, 0.86 - 0.89, and 0.92 - 0.96 sec.

Shot 23
Raised Ip to 1.2 MA. Disrupted at 1.08 sec. RF H-mode from 0.91 - 0.96 sec.

Shot 24
Lowered EF4 gain after 0.3 sec to 1. Disrupted at 1.02 sec with almost 1.2
MA. RF H-mode from 0.77 to 0.83 sec. H factor of about 1.0.

Shot 25
Lowered Ip to 0.6 MA and nel to 1.0 x 10^20 m^-2. Turned off B side upper
gas valve. Fizzle!

Shot 26
Try again. Good shot at 0.6 MA. ELMy RF H-mode from 0.8 - 1.0 sec.

Shot 27
Fizzle!

Shot 28
Try again. Good shot. ELMy RF H-mode from 0.82 - 1.01 sec.

Shot 29
Reduced nel to 9 x 10^19 m^-2. Good shot. RF only got 0.9 MW. No H-mode.


Session Leader Comments
May 5 1995 08:54:28:030AMSteve Golovatostarting with shot 950504018, an h-mode shot from yesterday.

May 5 1995 09:00:45:080AMSteve Golovatorun 950505 - continuation of yesterday's run on icrf h-modes.
main goal is to improve the h-factor by producing elm-free h-modes.
we will do a current scan, play with the gaps to control the loading
during h-mode to avoid rf voltage limits and to control whe nwe go
into h-mode, among other things.

May 5 1995 08:48:14:880AM950505001Steve Golovatoshot 950505001 - fizzle.

May 5 1995 09:13:03:150AM950505001Steve Golovatoshot 950505003 - plasma. nl=.9e20(just before rf), 1.8mw.
h-mode with 40ms elm-free phase during which density ramps
to 1.35e20.

May 5 1995 08:48:27:980AM950505002Steve Golovatoshot 950505002 - fizzle.

May 5 1995 09:13:09:120AM950505003Steve Golovatoshot 950505003 - plasma. nl=.9e20(just before rf), 1.8mw.
h-mode with 40ms elm-free phase during which density ramps
to 1.35e20.

May 5 1995 09:28:12:240AM950505004Steve Golovatoshot 950505004 - plasma. nl=.8e20(just before rf), 1.7mw.
h-mode, no elm-free phase.

May 5 1995 09:36:22:540AM950505005Steve Golovatoshot 950505005 - plasma. nl=.8e20(just before rf), 1.9mw.
moved plasma out by 6mm at start of rf to stay in l-mode,
then back in to get h-mode (if it works). very similar to last shot.

May 5 1995 10:12:10:120AM950505006Steve Golovatoshot 950505006 - plasma. nl=1.1e20(just before rf), 1.85mw.
raised density before rf then reduced it slightly so gas feed
is decreasing at h-mode transition. we seem to get elm-free
phase at higher density although threshold to higher.
got elm-free phase which ended at rf interrupt.

May 5 1995 10:28:44:150AM950505007Steve Golovatoshot 950505007 - plasma. nl=1.05e20(just before rf), 2.mw.
got elm-free phase ended by voltage max interrupts on both d and e.
lowering power to try to avoid this. we're getting very low loading
in this phase.

May 5 1995 10:44:32:540AM950505008Steve Golovatoshot 950505008 - plasma. nl=1.1e20(just before rf), 1.8.mw.
rf power drop avoided trips but h-mode ended at the same time.
we've moved the divdertor strike point down over the last two
shots by moving the x-point down and in. we will take one more
shot like this so brian can get a fsp scan during h-mode.

May 5 1995 11:06:16:750AM950505009Steve Golovatoshot 950505009 - plasma. nl=1.05e20(just before rf), 1.9.mw.
disrupted at .9 sec. similar h-mode to before. try moving plasma
out to maintain loading in h-mode, allowing higher power.

May 5 1995 11:15:49:670AM950505010Steve Golovatoshot 950505010 - plasma. early disruption at 550ms, before rf pulse.
had enabled argon, may have been too much. actually was a moly
event, but we'll shorten the argon puff as well.

May 5 1995 11:37:13:660AM950505011Steve Golovatoshot 950505011 - plasma. good shot again. nl=1.05. 1.9mw
same elm-free h-mode we've been getting, lasting about 40ms.
go to 1ma for next shot.

May 5 1995 11:54:59:960AM950505012Steve Golovatoshot 950505012 - plasma. nl=1.1e20, no d-port rf. 1MA
no h-modes. only 0.5mw

May 5 1995 12:15:00:880PM950505013Steve Golovatoshot 950505013 - plasma. nl=1.1e20, 1.7mw.
same h-mode. try rasing density.

May 5 1995 12:37:36:600PM950505014Steve Golovatoshot 950505014 - plasma. nl=1.1e20, 2mw.
density not higher. disruption at 950ms from moly injection.
200ka halo current (strike 1).

May 5 1995 12:45:58:120PM950505015Steve Golovatoshot 950505015 - plasma. nl=1.1e20, 2.5mw.
density not higher. a-side maxed out.

May 5 1995 12:46:57:490PM950505015Steve Golovatoshot 950505015 - got second elm-free phase, higher power is good!

May 5 1995 01:06:45:240PM950505016Steve Golovatoshot 950505016 - raising plenum pressure and moving rf back 50ms
to let density get higher before rf turn-on.
nl=1.3e20, 2.7mw. got several elm-free periods, need to link them
together. getting e-port trips.

May 5 1995 01:22:04:660PM950505017Steve Golovatoshot 950505017 - plasma. nl=1.3e20, 2.7mw. longer elm-free phase,
60ms.

May 5 1995 01:46:14:590PM950505018Steve Golovatoshot 950505018 - plasma. nl=1.3e20, 2.2mw.
d-port tripped at first, came on late. got 50ms elm-free phase,

May 5 1995 02:05:26:940PM950505019Steve Golovatoshot 950505019- plasma. nl=1.5e20, 2.3mw.
adding second puff valve to get more initial density.
rf running from 750-1000ms.
60ms h-mode.
both antennas tripping at first, come on at 820-840ms.

May 5 1995 02:28:40:540PM950505020Steve Golovatoshot 950505020- plasma. nl=1.5e20, 2.3mw.
d-port transmitter tripped at 810ms.
got h-mode at <1mw at 870ms, after d tripped.

May 5 1995 02:39:43:470PM950505021Steve Golovatoshot 950505021 - plasma. nl=1.5e20, 2.5mw.
got three h-mode phases, first for 70ms.
trying laser blow-off and fsp. take one more shot here for them.

May 5 1995 02:47:35:630PM950505022Steve Golovatoshot 950505022 - plasma. nl=1.4e20, 2.5mw.
3 h-modes. got a few rf trips.

May 5 1995 03:31:26:140PM950505023Steve Golovatoshot 950505023 - plasma. nl=1.3e20, 2.5mw.
going to 1.2 MA. got h-mode late.

May 5 1995 03:32:39:510PM950505024Steve Golovatoshot 950505024 - plasma. nl=1.35e20, 2.8mw. 1.2MA.
both transmitters tripped early, lost h-mode.

May 5 1995 03:48:34:330PM950505025Steve Golovatoshot 950505025 - plasma. nl=1.35e20, 2.8mw.
going to 600ka. fizzle.

May 5 1995 03:49:09:570PM950505025Steve Golovatoshot 950505025 - going to 600ka. fizzle, no plasma.

May 5 1995 04:25:00:160PM950505026Steve Golovatoshot 950505026 - plasma. nl=1.1e20. 2mw. 600ka.
elmy h-mode.

May 5 1995 04:25:22:620PM950505027Steve Golovatoshot 950505027 - fizzle.

May 5 1995 04:47:36:150PM950505028Steve Golovatoshot 950505028 - nl=1.1e20, 2.1mw. elmy h-mode.
density drops at 750ms, proprogramming turned off here.
looks just like shot 26.

May 5 1995 05:01:53:450PM950505029Steve Golovatoshot 950505029 - extending pre-programmed gas. lower nl to .9e20.
still got 1.1e20. no power on d-port.

Physics Operator Comments
May 5 1995 08:28:00:440AMJoseph SnipesRF H-mode Run
Set up by copying shot 950504018 but with nl04 = 7 x 10^19 m^-2 and shutting
off the pre-programmed gas after 0.6 sec. Fill set to 2.0 x 10^-5 Torr.
ICRF not yet ready for shot 1.

May 5 1995 08:44:13:480AM950505001Joseph SnipesShot 1
Pre fill set to 2.0 x 10^-5 Torr. nl04 set to 7 x 10^19 m^-2.
Reached 300 kA, but then disrupted. EFC fault that occurs after the plasma
disappears!? Lots of hard x rays.

May 5 1995 08:51:16:290AM950505002Joseph SnipesShot 2
Returned nel to 1.38 x 10^20 m^-2 as in shot 950504018. RF should be on for
this shot. Disrupted at 0.5 sec. Density rise too rapid. Reduced the rate of
rise of the density for shot 3.

May 5 1995 09:28:08:880AM950505002Joseph SnipesShot 2
Returned nel to 1.38 x 10^20 m^-2 as in shot 950504018. RF should be on for
this shot. Disrupted at 0.5 sec. Density rise too rapid. Reduced the rate of
rise of the density for shot 3.

May 5 1995 09:29:32:070AM950505003Joseph SnipesShot 3
Good shot. ICRF H-mode from 0.65 - 0.92 sec.

May 5 1995 09:32:02:330AM950505004Joseph SnipesShot 4
Reduced density to 1.1 x 10^20 m^-2. Good shot. ELMy ICRF H-mode from 0.65
to 0.9 sec.

May 5 1995 09:43:01:570AM950505005Joseph SnipesShot 5
Put a step in the RCUR of 3 mm from 0.5 to 0.8 sec to decrease the outer gap
while the density rises. ELMy RF H-mode 0.65 to almost 1 sec.

May 5 1995 10:00:10:010AM950505006Joseph SnipesShot 6
Raised density to 1.3 x 10^20 at 0.6 sec, maintaining the rate of rise of
the density before 0.5 sec to avoid disruptions. Then, lowered the density
to 1.2 x 10^20 m^-2 after 0.75 sec. Good shot. ELM-free RF H-mode 0.7 - 0.75 s.


May 5 1995 10:29:34:580AM950505007Joseph SnipesShot 7
Took out the step in RCUR. Moved ZXL down by 1 cm from 0.55 to 1.2 sec.
Good shot. ELM-free ICRF H-mode from 0.69 - 0.74 sec.

May 5 1995 10:37:35:730AM950505008Joseph SnipesShot 8
Decreased RXL by 5 mm during the flattop. Good shot. ELM-free ICRF H-mode
from 0.69 - 0.73 sec.

May 5 1995 10:42:31:420AM950505008Joseph SnipesShot 8
Decreased RXL by 5 mm during the flattop. Good shot. ELM-free ICRF H-mode
from 0.69 - 0.73 sec, then ELMy until 0.9 sec.

May 5 1995 11:05:39:950AM950505009Joseph SnipesShot 9
Repeat with FSP at 0.7 and 0.95 sec. Disrupted at 0.88 sec. Moly level rises
dramatically during RF. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy
until 0.8 sec.

May 5 1995 11:13:56:230AM950505010Joseph SnipesShot 10
Stepped out RCUR by 3 mm from 0.65 to 1.0 sec. Enabled Ar puff. Disrupted
at 0.55 sec. Too much Ar. Reduced puff by a factor of two in duration for
shot 11.

May 5 1995 11:15:30:980AM950505010Joseph SnipesShot 10
Stepped out RCUR by 3 mm from 0.65 to 1.0 sec. Enabled Ar puff. Disrupted
at 0.55 sec. Too much Ar. Reduced puff by a factor of two in duration for
shot 11. Correction. John was just feeling guilty. It was a large moly
injection that caused the disruption.

May 5 1995 11:37:44:750AM950505011Joseph SnipesShot 11
Repeat with shorter Ar puff. ELM-free RF H-mode from 0.69 to 0.73 sec, then
ELMy until 0.92 sec.

May 5 1995 11:51:54:680AM950505012Joseph SnipesShot 12
Longer Ar puff (28 ms). Ip raised to 1.0 MA. Disrupted at 1.15 sec. RF D port
antenna failed, so there was only 0.5 MW of RF power. No H-mode.

May 5 1995 12:10:11:260PM950505013Joseph SnipesShot 13
Repeat. Good shot. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy until
1.09 sec.

May 5 1995 12:25:08:830PM950505013Joseph SnipesShot 14
Raised programmed nel to 1.5 x 10^20 m^-2 hoping to get 1.4. Disrupted at
0.96 sec. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy until the
disruption.

May 5 1995 12:26:12:570PM950505014Joseph SnipesShot 14
Raised programmed nel to 1.5 x 10^20 m^-2 hoping to get 1.4. Disrupted at
0.96 sec. ELM-free RF H-mode from 0.69 - 0.73 sec, then ELMy until the
disruption. Moly injection at 0.9 sec led to the disruption.

May 5 1995 01:10:15:100PM950505015Joseph SnipesShot 15
Raised pre-programmed gas from 0.25 to 0.6 sec to try to increase the density.
Two RF H-modes from 0.69 - 0.73 and 0.81 - 0.86 sec. H factor 1.25.

May 5 1995 01:13:33:860PM950505016Joseph SnipesShot 16
Moved RF time to 0.7 sec. Good shot. Several RF H-modes from 0.72 to 0.92 sec.

May 5 1995 01:39:59:090PM950505017Joseph SnipesShot 17
Tweaked density to try to increase it a bit. Good shot. RF H-modes from 0.72
to 0.91 sec.

May 5 1995 01:44:56:310PM950505018Joseph SnipesShot 18
Repeat with A side plenum set to 20 psi. RF moved back to 0.75 sec. Good shot.
RF H-mode from 0.85 to 0.95 sec. H factor of 1.2.

May 5 1995 02:09:44:740PM950505019Joseph SnipesShot 19
Added B side upper gas valve to get more density. Set to 31 V from 0.3 to
0.75 sec. Good shot. ELM-free RF H-modes from 0.85 - 0.91 sec and 0.95 to
1.02 sec.

May 5 1995 02:17:09:220PM950505020Joseph SnipesShot 20
Repeat. Good shot. ELM-free RF H-modes from 0.78 - 0.83 and 0.87 - 0.92 sec.

May 5 1995 02:37:06:010PM950505021Joseph SnipesShot 21
Repeat with Sc injection at 0.775 sec. Good shot. 3 RF H-modes from 0.78 -
0.83, 0.87 - 0.9, and 0.92 - 0.95 sec. H factor of 1.35.

May 5 1995 02:58:17:180PM950505022Joseph SnipesShot 22
Repeat with Sc injection at 775 msec. Good shot. 3 RF H-modes 0.77 - 0.83,
0.86 - 0.89, and 0.92 - 0.96 sec.

May 5 1995 03:22:35:910PM950505023Joseph SnipesShot 23
Raised Ip to 1.2 MA. Disrupted at 1.08 sec. RF H-mode from 0.91 - 0.96 sec.

May 5 1995 03:36:44:610PM950505024Joseph SnipesShot 24
Lowered EF4 gain after 0.3 sec to 1. Disrupted at 1.02 sec with almost 1.2 MA.
RF H-mode from 0.77 to 0.83 sec. H factor of about 1.0.

May 5 1995 03:49:39:020PM950505025Joseph SnipesShot 25
Lowered Ip to 0.6 MA and nel to 1.0 x 10^20 m^-2. Turned off B side upper
gas valve. Fizzle!

May 5 1995 04:17:38:170PM950505026Joseph SnipesShot 26
Try again. Good shot at 0.6 MA. ELMy RF H-mode from 0.8 - 1.0 sec.

May 5 1995 04:50:57:320PM950505027Joseph SnipesShot 27
Fizzle!

May 5 1995 04:51:47:130PM950505028Joseph SnipesShot 28
Try again. Good shot. ELMy RF H-mode from 0.82 - 1.01 sec.

May 5 1995 05:07:01:260PM950505029Joseph SnipesShot 29
Reduced nel to 9 x 10^19 m^-2. Good shot. RF only got 0.9 MW. No H-mode.

Engineering Operator Comments
ShotTimeTypeStatusComment
108:27:21:570AMPlasmaOk
208:44:41:680AMPlasmaOk
308:54:25:920AMPlasmaOk
409:12:15:540AMPlasmaOk
509:30:45:420AMPlasmaOk
609:47:27:130AMPlasmaOk
710:12:31:300AMPlasmaOk
810:30:28:760AMPlasmaOk
910:48:24:940AMPlasmaOk
1011:07:57:960AMPlasmaOk
1111:24:47:100AMPlasmaOk
1211:41:37:630AMPlasmaOk
1311:59:14:130AMPlasmaOk
1412:18:08:630PMPlasmaOk
1512:35:25:640PMPlasmaOk
1612:53:02:530PMPlasmaOk
1701:10:25:410PMPlasmaOkNo Faults.
1801:27:15:410PMPlasmaOkNo Faults.
1901:45:24:580PMPlasmaOkNo Faults.
2002:03:25:140PMPlasmaOkNo Faults.
2102:24:03:650PMPlasmaOkNo Faults
2202:41:09:910PMPlasmaOkno faults
2303:00:52:230PMPlasmaOkno faults
2403:25:13:200PMPlasmaOkno faults
2503:42:15:860PMPlasmaOkNo Faults.
2604:05:00:030PMPlasmaOkNo Faults.
2704:22:05:760PMPlasmaOkNo faults.
2804:38:49:680PMPlasmaOkNo Faults.
2904:55:41:660PMPlasmaOkNo Faults.