Alcator C-Mod Run 931013 Information

Miniproposals

Miniproposal:

Date Filed:

Title:

First Author:

Session Leader: Tom Luke (shots 1-23)

Operators
Session leader(s):	Tom Luke
Physics operator(s):	Joseph Snipes
Engineering operator(s):	Frank Silva

Engineering Operator Run Comment
tom luke/thises

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:09:273PM

Author: To Be Determined

From: GANESA::SNIPES
Date: 13-OCT-1993 18:51:32
Description: Run Summary 931013

Overall it was a good run. The intention of the run was to operate at or
near the density limit and to measure particle diffusion with gas puffing.
There was about an hour delay in the morning due to computer problems in
that SCOPE's were hanging and unable to plot data. Nonetheless there were

19 plasmas
2 fizzles
2 duds.

Not a bad average.
Plasmas were run with currents from 750 kA to 800 kA with TF at 5.2 T.
Line averaged densities above 1.0 x 10**20 /m**2 were obtained.
Almost all plasmas disrupted mainly resulting from hard
gas puffing leading to "shark fins" during the current rampdown. There were
also some pellet induced disruptions and at least one snake (931013019).

In addition to the gas puffing, scanning probe data was taken on several
shots, scandium injections were made on some shots, and ICRH power was
coupled to many of the shots. Indeed, it may be that the relatively good
reliability of the plasma breakdown was due to RF assisted start up after
shot 3.

Physics Operator Summaries

Session Leader Comments

Oct 13 1993 09:40:07:240AM Tom Luke Session Leader: Thomas Luke
Physics Operator: Joe Snipes
Engineering Operator: Frank Silva.

Today's run will atytempt to accomplish the goals of MP 30, a study of
transport at the density limit. Shots will try to reach a high
density (4-8 10^19) in conjunction with a current rampdown. Gas puffs
will be initiated throughout the shots in order to measure the diffusion
coefficients. Pellet Injection may be required to reach the higher
density levels.

Oct 13 1993 09:45:41:040AM Tom Luke Session Leader: Thomas Luke
Physics Operator: Joe Snipes
Engineering Operator: Frank Silva.

Today's run will attempt to accomplish the goals of MP 30, a study of
transport at the density limit. Shots will try to reach a high
density (4-8 10^19) in conjunction with a current rampdown. Gas puffs
will be initiated throughout the shots in order to measure the diffusion
coefficients. Pellet Injection may be required to reach the higher
density levels.

Oct 13 1993 10:14:19:620AM 931013001 Tom Luke Repeat shot 5 form 10/12 but with a current rampdown starting at 600ms.
Reach a peak nl of 1.0e20 and the current ramps down nicely until
200 kA. Peak current of 800 kA. Marfe forms at 750 ms.

Oct 13 1993 10:30:08:470AM 931013001 Tom Luke Similiar shot but we drop the gas fill at 700 ms to 40 V to see if we
can avoid the marfe. No breakdown. Dud.

Oct 13 1993 10:46:54:240AM 931013002 Tom Luke Try again. Drop prefill to 1.1e-5 torr. Extend gas puff to .9 s.
Got a flash. Broke down late. Not enough gas.

Oct 13 1993 11:18:11:490AM 931013003 Tom Luke Try again. Bring prefill back to 1.2e-5. Turn on RF at 300 ms. Argon
turned on. Shot went. Dirupted at .9 after a short shark fin.

Oct 13 1993 11:37:54:310AM 931013005 Tom Luke Raise gas fill to 50 V up to .9s. Disrupted at 875. Lost some of the
data system.

Oct 13 1993 11:53:23:500AM 931013006 Tom Luke TRy again. Ramp down gas from 600 ms to 1 s. Try again to avoid marfe.
Disrupts at .96 s. Peak density is 1.0e20.

Oct 13 1993 12:08:22:190PM 931013007 Tom Luke TRy again. Ramp down gas from 600 ms to 1 s. Try again to avoid marfe.
HIgher density 1.5e20. Disrupts at.9 s. Getting closer.

Oct 13 1993 12:44:00:870PM 931013007 Tom Luke TRy again. Ramp down gas earlier at 500 ms. Raise gas puff to 60V.High
densities (2.0e20 on the inside). Still disrupts at .7 s.

Oct 13 1993 12:56:06:370PM 931013009 Tom Luke Raise initial gas to 65V. Raise current limit to 800 kA. Cut off gas at 600 ms.
Short pulse. Disrupted at 400 ms. Inside density is up to 1.0e20.

Oct 13 1993 01:08:28:450PM 931013010 Tom Luke Lower gas puff voltage to 60V . Same shot as 09.Disrupts at 850 ms.
Density is 1.4e20.

Oct 13 1993 01:16:50:210PM 931013010 Tom Luke Add a gas puff at 700 ms. 60V puff for 20 ms.

Oct 13 1993 01:47:22:600PM 931013012 Tom Luke Add a second puff at 400 ms, 100V, 20 ms long. Puff at 700 ms increased
to 100V. Otherwise same shot as 10 and 11.Disrupts at 800 ms. THe 700 ms puff
is lost in the fin and the 400 ms puff is too small.

Oct 13 1993 02:04:56:330PM 931013013 Tom Luke Create an inverse puff (turn gas voltage to zero) for 30 ms at 400 ms. Extend
current profile out to 800 ms. Hopefully, 700 ms puff will be seperated from
the shark fin. Disrupt at 1.07 s. See both the inverse and positive puffs
clearly

Oct 13 1993 02:17:14:220PM 931013014 Tom Luke Modulated gas puffing . Square wave pulses. 30 ms at 100V and then 100ms at
zero volts. Fizzle. Try again

Oct 13 1993 02:41:26:270PM 931013015 Tom Luke Modulated gas puffing. Clearly see the puffs.

Oct 13 1993 03:04:00:080PM 931013015 Tom Luke Modulated gas puffing. With rampdown starting at 500 ms.
Disrupted at 840 ms at 400 kA. See the gas puffs.

Oct 13 1993 03:04:48:980PM 931013016 Tom Luke Modulated gas puffing. With rampdown starting at 500 ms.
Disrupted at 840 ms at 400 kA. See the gas puffs.

Oct 13 1993 03:28:41:580PM 931013017 Tom Luke We are doing a current stepdown. 200 KA stps at 500 and 750 ms. Pellet shot
in at 550 ms. Gas puff of 1100V for 30 ms at 700 and 900 ms. Disrupted
due to a shark fin at 900 ms. See the pellet and gas puff at 700 ms.

Oct 13 1993 03:47:40:250PM 931013018 Tom Luke We are doing a current stepdown. 300 kA at 500 ms. Gas puffs of 100v at 600 and
800 ms. Pellet was larger size and disrupted the plasma at 700 ms.

Oct 13 1993 03:47:44:690PM 931013018 Tom Luke We are doing a current stepdown. 300 kA at 500 ms. Gas puffs of 100v at 600 and
800 ms. Pellet was larger size and disrupted the plasma at 700 ms.

Oct 13 1993 04:06:17:280PM 931013019 Tom Luke Try again with smaller pellet at 700 ms. Everything the same otherwise. See
the early gas puff and the pellet. second gas puff or the shark fin then
causes a disruption.

Oct 13 1993 04:25:41:290PM 931013020 Tom Luke Inject larger pellet at 500 ms . Everything else the same. Pellet raises
density to above 2.0e20 and it is disrupted by gas puff at 700ms.

Oct 13 1993 04:50:04:760PM 931013021 Tom Luke Inject larger pellet at 500 ms . 6 small gas puffs (30 ms and 60V) after
500 ms. Again we see the pellet and two of the small puffs. We disrupt after
the third puff.

Oct 13 1993 04:56:29:540PM 931013022 Tom Luke Modulated gas puffing throughout the whole shot. No rampdown. Dud.

Oct 13 1993 04:56:37:710PM 931013022 Tom Luke Modulated gas puffing throughout the whole shot. No rampdown. Dud.

Oct 13 1993 05:13:30:080PM 931013023 Tom Luke same as 22. modulated gas puff. Disrupted at 1.03 s. See modulation on
H-alpha and TCI

Physics Operator Comments

Oct 13 1993 09:42:38:050AM Joseph Snipes Density Limit Current Ramps

Session Leader: Tom Luke
Physics Operator: Joe Snipes
Engineer in Charge: Frank Silva

This run is intended to determine the density limit by ramping down the
current and gas puffing during the rampdown. We will start by copying
931012005 and changing only the plasma current waveform to start ramping
down from 0.6 s to zero at 1.2 s.

Oct 13 1993 05:36:43:400PM Joseph Snipes Run Summary 931013

Overall it was a good run. The intention of the run was to operate at or
near the density limit and to measure particle diffusion with gas puffing.
There was about an hour delay in the morning due to computer problems in
that SCOPE's were hanging and unable to plot data. Nonetheless there were

19 plasmas
2 fizzles
2 duds.

Not a bad days run. Almost all plasmas disrupted mainly resulting from hard
gas puffing leading to "shark fins" during the current rampdown. There were
also some pellet induced disruptions and at least one snake (931013019).

Oct 13 1993 10:19:02:620AM 931013001 Joseph Snipes Shot 1
Start with a prefill of 1.2 x 10**-5 Torr. Shot 931012005 was copied except
that the Ip waveform was ramped down from 0.6 s to zero at 1.2 s.
Good shot!

Oct 13 1993 10:25:57:530AM 931013001 Joseph Snipes Shot 2
Stepped gas puff down from 46 V to 35 V at 0.7 s to avoid the MARFE that
appears at 0.75 s.
Dud!

Oct 13 1993 10:40:46:460AM 931013002 Joseph Snipes Shot 3
Stepped gas puff down from 46 V to 37 V at 0.7 s and extended the puff out
to 0.9 s. Reduced prefill to 1.1 x 10**-5 Torr.
Fizzle!

Oct 13 1993 11:15:37:930AM 931013004 Joseph Snipes Shot 4
Increased prefill back to 1.2 x 10**-5 Torr. Try ICRH assisted breakdown
to make the breakdown more robust. Turn on Ar gas puff.
RF not ready. Good shot.

Oct 13 1993 11:38:15:390AM 931013005 Joseph Snipes Shot 5
Increased gas from 0.15 s to 0.9 s up to 50 V.
Good shot.

Oct 13 1993 11:46:29:400AM 931013006 Joseph Snipes Shot 6
Ramped gas from 0.6 s to 0.9 s from 50 V to 0.
Good shot.

Oct 13 1993 11:56:30:290AM 931013006 Joseph Snipes Shot 7
Raised gas to 55 V from 0.1 to 0.6 s. Ramped gas from 0.6 s to 1.0 s from
55 V to 0.
Good shot!

Oct 13 1993 12:12:36:710PM 931013008 Joseph Snipes Shot 8
Increased Ar a bit. Increased gas from 55 V to 60 V from 0.1 to 0.6 s.
Started current rampdown at 0.5 s.
Good shot.

Oct 13 1993 12:50:10:820PM 931013009 Joseph Snipes Shot 9
Increased gas from 60 V to 65 V from 0.1 to 0.6 s.
Deleted gas rampdown so that it drops to zero at 0.6 s. Increased Ip to 800 kA
from 0.32 s to 0.5.
Disrupted at 300 ms.

Oct 13 1993 05:25:12:990PM 931013010 Joseph Snipes Shot 10
Gas shut off at 0.6 s.
Good shot.

Oct 13 1993 01:26:11:670PM 931013011 Joseph Snipes Shot 11
Added gas puff at 0.7 s for 20 ms at 60 V.
Good shot.

Oct 13 1993 01:32:51:210PM 931013012 Joseph Snipes Shot 12
Added gas puff at 0.4 s for 20 ms at 100 V. Increased 60 V puff to 100 V at
0.7 s. Scanning probe inserted at 0.5 s.
Good shot!

Oct 13 1993 02:04:41:460PM 931013013 Joseph Snipes Shot 13
Changed puff at 0.4 s to an inverse puff, asking the valve voltage to go to
zero for 30 ms. Extended the current flattop out to 0.8 s.
Good shot.

Oct 13 1993 02:15:42:650PM 931013014 Joseph Snipes Shot 14
Modulated gas puffing from 0.5 s from 60 to 100 V for 30 ms, then off for
100 ms then on for 30 ms then off for 100 ms then on for 30 ms again.
Fizzle!

Oct 13 1993 02:33:36:310PM 931013015 Joseph Snipes Shot 15
Modulated gas puffing from 0.5 s from 60 to 100 V for 30 ms, then off for
100 ms then on for 30 ms then off for 100 ms then on for 30 ms again.
One more time . . .
Good shot!

Oct 13 1993 02:48:23:650PM 931013016 Joseph Snipes Shot 16
Redo the gas puff modulation with a current ramp down at 0.5 s to zero at
1.2 s. Take out the inverse puff at 0.4 s. Scandium injection at 0.45 s.
Decent shot.

Oct 13 1993 03:10:28:650PM 931013017 Joseph Snipes Shot 17
Ramping down the current in two steps from 800 kA at 0.5 s to 600 kA at 0.6 s
then ramping from 0.75 s to 400 kA at 0.85 s then ramping from 1.0 s to 0 at
1.2 s. Then, there will be gas puffs at 0.7 s for 30 ms at 100 V and at 0.9 s
for 30 ms at 100 V. Then, there will also be a pellet at 0.55 s, a Sc
injection at 0.45 s and a probe going in at 0.5 s.
Good shot.

Oct 13 1993 03:38:52:900PM 931013017 Joseph Snipes Shot 18
Ramping down the current in one step from 800 kA at 0.5 s to 500 kA at 0.7 s
then ramping from 0.95s to 0 at 1.2 s. Then, there will be gas puffs at 0.6 s
for 50 ms at 100 V and at 0.8 s for 50 ms at 100 V. Then, there will also be a
pellet at 0.7 s, a Sc injection at 0.45 s and a probe going in at 0.5 s.
Disrupted at the pellet.

Oct 13 1993 03:39:00:480PM 931013018 Joseph Snipes Shot 18
Ramping down the current in one step from 800 kA at 0.5 s to 500 kA at 0.7 s
then ramping from 0.95s to 0 at 1.2 s. Then, there will be gas puffs at 0.6 s
for 50 ms at 100 V and at 0.8 s for 50 ms at 100 V. Then, there will also be a
pellet at 0.7 s, a Sc injection at 0.45 s and a probe going in at 0.5 s.
Disrupted at the pellet.

Oct 13 1993 04:06:26:500PM 931013019 Joseph Snipes Shot 19
Small pellet at 0.7 s. No other change.
Good shot. Snake after the pellet.

Oct 13 1993 04:17:56:030PM 931013020 Joseph Snipes Shot 20
Big pellet at 0.5 s. No other change.
Good shot. Interesting MHD at 0.525 to 0.53 s on SXR.

Oct 13 1993 04:49:40:670PM 931013021 Joseph Snipes Shot 21
Changed ramp of the current to a linear ramp from 800 kA to zero from 0.5 s
to 1.2 s. Put in a series of 80 V, 30 ms gas puffs after 0.5 s. Medium
pellet at 0.5 s.
Good shot.

Oct 13 1993 04:57:38:530PM 931013022 Joseph Snipes Shot 22
Maintained 800 kA flattop of Ip out to 0.8 s. Six gas puffs out to 0.9 s.
No pellet.
Dud.

Oct 13 1993 05:05:22:810PM 931013023 Joseph Snipes Shot 23
One more time . . .
Good shot.

Engineering Operator Comments

Shot Time Type Status Comment

1 09:59:57:190AM Plasma Ok

2 10:21:16:870AM Plasma Ok

3 10:38:05:270AM Plasma Ok

4 10:56:37:300AM Plasma Ok

5 11:19:02:170AM Plasma Ok

6 11:40:11:320AM Plasma Ok

7 11:54:16:520AM Plasma Ok

8 12:09:54:300PM Plasma Ok

9 12:44:16:010PM Plasma Ok

10 12:57:42:060PM Plasma Ok

11 01:13:47:840PM Plasma Ok

12 01:29:23:770PM Plasma Ok

13 01:54:15:970PM Plasma Ok

14 02:10:24:660PM Plasma Ok

15 02:28:04:610PM Plasma Ok

16 02:45:47:890PM Plasma Ok

17 03:07:36:870PM Plasma Ok

18 03:31:56:840PM Plasma Ok

19 03:51:07:940PM Plasma Ok

20 04:07:22:270PM Plasma Ok

21 04:30:28:090PM Plasma Ok

22 04:51:53:960PM Plasma Ok

23 05:03:22:440PM Plasma Ok

Session Leader Comments
Oct 13 1993 09:40:07:240AM		Tom Luke	Session Leader: Thomas Luke Physics Operator: Joe Snipes Engineering Operator: Frank Silva. Today's run will atytempt to accomplish the goals of MP 30, a study of transport at the density limit. Shots will try to reach a high density (4-8 10^19) in conjunction with a current rampdown. Gas puffs will be initiated throughout the shots in order to measure the diffusion coefficients. Pellet Injection may be required to reach the higher density levels.
Oct 13 1993 09:45:41:040AM		Tom Luke	Session Leader: Thomas Luke Physics Operator: Joe Snipes Engineering Operator: Frank Silva. Today's run will attempt to accomplish the goals of MP 30, a study of transport at the density limit. Shots will try to reach a high density (4-8 10^19) in conjunction with a current rampdown. Gas puffs will be initiated throughout the shots in order to measure the diffusion coefficients. Pellet Injection may be required to reach the higher density levels.
Oct 13 1993 10:14:19:620AM	931013001	Tom Luke	Repeat shot 5 form 10/12 but with a current rampdown starting at 600ms. Reach a peak nl of 1.0e20 and the current ramps down nicely until 200 kA. Peak current of 800 kA. Marfe forms at 750 ms.
Oct 13 1993 10:30:08:470AM	931013001	Tom Luke	Similiar shot but we drop the gas fill at 700 ms to 40 V to see if we can avoid the marfe. No breakdown. Dud.
Oct 13 1993 10:46:54:240AM	931013002	Tom Luke	Try again. Drop prefill to 1.1e-5 torr. Extend gas puff to .9 s. Got a flash. Broke down late. Not enough gas.
Oct 13 1993 11:18:11:490AM	931013003	Tom Luke	Try again. Bring prefill back to 1.2e-5. Turn on RF at 300 ms. Argon turned on. Shot went. Dirupted at .9 after a short shark fin.
Oct 13 1993 11:37:54:310AM	931013005	Tom Luke	Raise gas fill to 50 V up to .9s. Disrupted at 875. Lost some of the data system.
Oct 13 1993 11:53:23:500AM	931013006	Tom Luke	TRy again. Ramp down gas from 600 ms to 1 s. Try again to avoid marfe. Disrupts at .96 s. Peak density is 1.0e20.
Oct 13 1993 12:08:22:190PM	931013007	Tom Luke	TRy again. Ramp down gas from 600 ms to 1 s. Try again to avoid marfe. HIgher density 1.5e20. Disrupts at.9 s. Getting closer.
Oct 13 1993 12:44:00:870PM	931013007	Tom Luke	TRy again. Ramp down gas earlier at 500 ms. Raise gas puff to 60V.High densities (2.0e20 on the inside). Still disrupts at .7 s.
Oct 13 1993 12:56:06:370PM	931013009	Tom Luke	Raise initial gas to 65V. Raise current limit to 800 kA. Cut off gas at 600 ms. Short pulse. Disrupted at 400 ms. Inside density is up to 1.0e20.
Oct 13 1993 01:08:28:450PM	931013010	Tom Luke	Lower gas puff voltage to 60V . Same shot as 09.Disrupts at 850 ms. Density is 1.4e20.
Oct 13 1993 01:16:50:210PM	931013010	Tom Luke	Add a gas puff at 700 ms. 60V puff for 20 ms.
Oct 13 1993 01:47:22:600PM	931013012	Tom Luke	Add a second puff at 400 ms, 100V, 20 ms long. Puff at 700 ms increased to 100V. Otherwise same shot as 10 and 11.Disrupts at 800 ms. THe 700 ms puff is lost in the fin and the 400 ms puff is too small.
Oct 13 1993 02:04:56:330PM	931013013	Tom Luke	Create an inverse puff (turn gas voltage to zero) for 30 ms at 400 ms. Extend current profile out to 800 ms. Hopefully, 700 ms puff will be seperated from the shark fin. Disrupt at 1.07 s. See both the inverse and positive puffs clearly
Oct 13 1993 02:17:14:220PM	931013014	Tom Luke	Modulated gas puffing . Square wave pulses. 30 ms at 100V and then 100ms at zero volts. Fizzle. Try again
Oct 13 1993 02:41:26:270PM	931013015	Tom Luke	Modulated gas puffing. Clearly see the puffs.
Oct 13 1993 03:04:00:080PM	931013015	Tom Luke	Modulated gas puffing. With rampdown starting at 500 ms. Disrupted at 840 ms at 400 kA. See the gas puffs.
Oct 13 1993 03:04:48:980PM	931013016	Tom Luke	Modulated gas puffing. With rampdown starting at 500 ms. Disrupted at 840 ms at 400 kA. See the gas puffs.
Oct 13 1993 03:28:41:580PM	931013017	Tom Luke	We are doing a current stepdown. 200 KA stps at 500 and 750 ms. Pellet shot in at 550 ms. Gas puff of 1100V for 30 ms at 700 and 900 ms. Disrupted due to a shark fin at 900 ms. See the pellet and gas puff at 700 ms.
Oct 13 1993 03:47:40:250PM	931013018	Tom Luke	We are doing a current stepdown. 300 kA at 500 ms. Gas puffs of 100v at 600 and 800 ms. Pellet was larger size and disrupted the plasma at 700 ms.
Oct 13 1993 03:47:44:690PM	931013018	Tom Luke	We are doing a current stepdown. 300 kA at 500 ms. Gas puffs of 100v at 600 and 800 ms. Pellet was larger size and disrupted the plasma at 700 ms.
Oct 13 1993 04:06:17:280PM	931013019	Tom Luke	Try again with smaller pellet at 700 ms. Everything the same otherwise. See the early gas puff and the pellet. second gas puff or the shark fin then causes a disruption.
Oct 13 1993 04:25:41:290PM	931013020	Tom Luke	Inject larger pellet at 500 ms . Everything else the same. Pellet raises density to above 2.0e20 and it is disrupted by gas puff at 700ms.
Oct 13 1993 04:50:04:760PM	931013021	Tom Luke	Inject larger pellet at 500 ms . 6 small gas puffs (30 ms and 60V) after 500 ms. Again we see the pellet and two of the small puffs. We disrupt after the third puff.
Oct 13 1993 04:56:29:540PM	931013022	Tom Luke	Modulated gas puffing throughout the whole shot. No rampdown. Dud.
Oct 13 1993 04:56:37:710PM	931013022	Tom Luke	Modulated gas puffing throughout the whole shot. No rampdown. Dud.
Oct 13 1993 05:13:30:080PM	931013023	Tom Luke	same as 22. modulated gas puff. Disrupted at 1.03 s. See modulation on H-alpha and TCI

Physics Operator Comments
Oct 13 1993 09:42:38:050AM		Joseph Snipes	Density Limit Current Ramps Session Leader: Tom Luke Physics Operator: Joe Snipes Engineer in Charge: Frank Silva This run is intended to determine the density limit by ramping down the current and gas puffing during the rampdown. We will start by copying 931012005 and changing only the plasma current waveform to start ramping down from 0.6 s to zero at 1.2 s.
Oct 13 1993 05:36:43:400PM		Joseph Snipes	Run Summary 931013 Overall it was a good run. The intention of the run was to operate at or near the density limit and to measure particle diffusion with gas puffing. There was about an hour delay in the morning due to computer problems in that SCOPE's were hanging and unable to plot data. Nonetheless there were 19 plasmas 2 fizzles 2 duds. Not a bad days run. Almost all plasmas disrupted mainly resulting from hard gas puffing leading to "shark fins" during the current rampdown. There were also some pellet induced disruptions and at least one snake (931013019).
Oct 13 1993 10:19:02:620AM	931013001	Joseph Snipes	Shot 1 Start with a prefill of 1.2 x 10**-5 Torr. Shot 931012005 was copied except that the Ip waveform was ramped down from 0.6 s to zero at 1.2 s. Good shot!
Oct 13 1993 10:25:57:530AM	931013001	Joseph Snipes	Shot 2 Stepped gas puff down from 46 V to 35 V at 0.7 s to avoid the MARFE that appears at 0.75 s. Dud!
Oct 13 1993 10:40:46:460AM	931013002	Joseph Snipes	Shot 3 Stepped gas puff down from 46 V to 37 V at 0.7 s and extended the puff out to 0.9 s. Reduced prefill to 1.1 x 10**-5 Torr. Fizzle!
Oct 13 1993 11:15:37:930AM	931013004	Joseph Snipes	Shot 4 Increased prefill back to 1.2 x 10**-5 Torr. Try ICRH assisted breakdown to make the breakdown more robust. Turn on Ar gas puff. RF not ready. Good shot.
Oct 13 1993 11:38:15:390AM	931013005	Joseph Snipes	Shot 5 Increased gas from 0.15 s to 0.9 s up to 50 V. Good shot.
Oct 13 1993 11:46:29:400AM	931013006	Joseph Snipes	Shot 6 Ramped gas from 0.6 s to 0.9 s from 50 V to 0. Good shot.
Oct 13 1993 11:56:30:290AM	931013006	Joseph Snipes	Shot 7 Raised gas to 55 V from 0.1 to 0.6 s. Ramped gas from 0.6 s to 1.0 s from 55 V to 0. Good shot!
Oct 13 1993 12:12:36:710PM	931013008	Joseph Snipes	Shot 8 Increased Ar a bit. Increased gas from 55 V to 60 V from 0.1 to 0.6 s. Started current rampdown at 0.5 s. Good shot.
Oct 13 1993 12:50:10:820PM	931013009	Joseph Snipes	Shot 9 Increased gas from 60 V to 65 V from 0.1 to 0.6 s. Deleted gas rampdown so that it drops to zero at 0.6 s. Increased Ip to 800 kA from 0.32 s to 0.5. Disrupted at 300 ms.
Oct 13 1993 05:25:12:990PM	931013010	Joseph Snipes	Shot 10 Gas shut off at 0.6 s. Good shot.
Oct 13 1993 01:26:11:670PM	931013011	Joseph Snipes	Shot 11 Added gas puff at 0.7 s for 20 ms at 60 V. Good shot.
Oct 13 1993 01:32:51:210PM	931013012	Joseph Snipes	Shot 12 Added gas puff at 0.4 s for 20 ms at 100 V. Increased 60 V puff to 100 V at 0.7 s. Scanning probe inserted at 0.5 s. Good shot!
Oct 13 1993 02:04:41:460PM	931013013	Joseph Snipes	Shot 13 Changed puff at 0.4 s to an inverse puff, asking the valve voltage to go to zero for 30 ms. Extended the current flattop out to 0.8 s. Good shot.
Oct 13 1993 02:15:42:650PM	931013014	Joseph Snipes	Shot 14 Modulated gas puffing from 0.5 s from 60 to 100 V for 30 ms, then off for 100 ms then on for 30 ms then off for 100 ms then on for 30 ms again. Fizzle!
Oct 13 1993 02:33:36:310PM	931013015	Joseph Snipes	Shot 15 Modulated gas puffing from 0.5 s from 60 to 100 V for 30 ms, then off for 100 ms then on for 30 ms then off for 100 ms then on for 30 ms again. One more time . . . Good shot!
Oct 13 1993 02:48:23:650PM	931013016	Joseph Snipes	Shot 16 Redo the gas puff modulation with a current ramp down at 0.5 s to zero at 1.2 s. Take out the inverse puff at 0.4 s. Scandium injection at 0.45 s. Decent shot.
Oct 13 1993 03:10:28:650PM	931013017	Joseph Snipes	Shot 17 Ramping down the current in two steps from 800 kA at 0.5 s to 600 kA at 0.6 s then ramping from 0.75 s to 400 kA at 0.85 s then ramping from 1.0 s to 0 at 1.2 s. Then, there will be gas puffs at 0.7 s for 30 ms at 100 V and at 0.9 s for 30 ms at 100 V. Then, there will also be a pellet at 0.55 s, a Sc injection at 0.45 s and a probe going in at 0.5 s. Good shot.
Oct 13 1993 03:38:52:900PM	931013017	Joseph Snipes	Shot 18 Ramping down the current in one step from 800 kA at 0.5 s to 500 kA at 0.7 s then ramping from 0.95s to 0 at 1.2 s. Then, there will be gas puffs at 0.6 s for 50 ms at 100 V and at 0.8 s for 50 ms at 100 V. Then, there will also be a pellet at 0.7 s, a Sc injection at 0.45 s and a probe going in at 0.5 s. Disrupted at the pellet.
Oct 13 1993 03:39:00:480PM	931013018	Joseph Snipes	Shot 18 Ramping down the current in one step from 800 kA at 0.5 s to 500 kA at 0.7 s then ramping from 0.95s to 0 at 1.2 s. Then, there will be gas puffs at 0.6 s for 50 ms at 100 V and at 0.8 s for 50 ms at 100 V. Then, there will also be a pellet at 0.7 s, a Sc injection at 0.45 s and a probe going in at 0.5 s. Disrupted at the pellet.
Oct 13 1993 04:06:26:500PM	931013019	Joseph Snipes	Shot 19 Small pellet at 0.7 s. No other change. Good shot. Snake after the pellet.
Oct 13 1993 04:17:56:030PM	931013020	Joseph Snipes	Shot 20 Big pellet at 0.5 s. No other change. Good shot. Interesting MHD at 0.525 to 0.53 s on SXR.
Oct 13 1993 04:49:40:670PM	931013021	Joseph Snipes	Shot 21 Changed ramp of the current to a linear ramp from 800 kA to zero from 0.5 s to 1.2 s. Put in a series of 80 V, 30 ms gas puffs after 0.5 s. Medium pellet at 0.5 s. Good shot.
Oct 13 1993 04:57:38:530PM	931013022	Joseph Snipes	Shot 22 Maintained 800 kA flattop of Ip out to 0.8 s. Six gas puffs out to 0.9 s. No pellet. Dud.
Oct 13 1993 05:05:22:810PM	931013023	Joseph Snipes	Shot 23 One more time . . . Good shot.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:59:57:190AM	Plasma	Ok
2	10:21:16:870AM	Plasma	Ok
3	10:38:05:270AM	Plasma	Ok
4	10:56:37:300AM	Plasma	Ok
5	11:19:02:170AM	Plasma	Ok
6	11:40:11:320AM	Plasma	Ok
7	11:54:16:520AM	Plasma	Ok
8	12:09:54:300PM	Plasma	Ok
9	12:44:16:010PM	Plasma	Ok
10	12:57:42:060PM	Plasma	Ok
11	01:13:47:840PM	Plasma	Ok
12	01:29:23:770PM	Plasma	Ok
13	01:54:15:970PM	Plasma	Ok
14	02:10:24:660PM	Plasma	Ok
15	02:28:04:610PM	Plasma	Ok
16	02:45:47:890PM	Plasma	Ok
17	03:07:36:870PM	Plasma	Ok
18	03:31:56:840PM	Plasma	Ok
19	03:51:07:940PM	Plasma	Ok
20	04:07:22:270PM	Plasma	Ok
21	04:30:28:090PM	Plasma	Ok
22	04:51:53:960PM	Plasma	Ok
23	05:03:22:440PM	Plasma	Ok