Alcator C-Mod Run 990825 Information

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Miniproposals
Miniproposal:208
Date Filed: 1/4/1999
Title:Burping Probe and Plume Imaging Systems Commissioning
First Author:Brian Labombard
Session Leader:Sanjay Gangadhara (shots 1-22)
Session Leader:Brian Labombard (shots 1-22)

Operators
Session leader(s):Sanjay Gangadhara,Brian Labombard
Physics operator(s):Joseph Snipes
Engineering operator(s): Unknown

Engineering Operator Run Comment
Run Plan for Wed. AUG. 25, 1999. MP#208/228 PLumes and SOL Transport. La

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:20:990PM
Author: To Be Determined
Session Leader's summary of run 990825
MP#208 - Plume Imaging
MP#228 - SOL Transport

Physics Operator: Snipes
Session Leader: LaBombard,Gangadhara

Given the rare opportunity to collect some data
for MP#208 and MP#228 during this period of otherwise intense
focus on RF commissioning and conditioning, we developed a rather
ambitious run plan. In one run, we attempted to finish MP#208
and to provide some badly needed Bt scaling data by way of ohmic
H-modes for the SOL transport studies in MP#228. In the end, we
settled on doing a good job to finish MP#208 at the cost of deferring
any work on MP#228 to another run - the risk being that another
dedicated run for MP#228 may not happen in this campaign.

================================================================================
First half Run Plan:
================================================================================
Plume Imaging MP#208

Objectives:

Capture images of CII and CIII "plumes" to provide information on
parallel and cross-field transport in the SOL in a variety of ohmic
plasma conditions:

(1) Investigate the dependence of cross-field spreading of C+1, C+2
(i.e., cross-field transport) at fixed locations in the SOL as
a function of plasma density (or collisionality)
(2) Investigate dependence of cross-field impurity transport on
SOL location (rho) in fixed discharge conditions
(3) Investigate parallel flow of background plasma (via parallel C+1, C+2 spreading)
as a function of SOL location and plasma collisionality.

Setup:
FSP: - Operate in two bias modes:
(a) West/East-sweep, North/South-float mode
(b) West/South-sweep, North/East-float mode
- Enable gas (C2H4) for plumes
- Set up for a "deep" scan to the separatrix
- Set up for a "shallow" scan to about rho=7 mm
(10 mm below LCFS target in vertical position)

ASP: - Operate in two bias modes: (South probe is dead!)
(a) West/East-sweep, North-float mode
(b) West-sweep, North/East-float mode
- Set up for a "deep" scan to the separatrix with
current sensing resistor set at 2 ohms
- Set up for a "shallow" scan to about rho=10 mm with
current sensing resistor set at 10 ohms

FMP: - Operate in two bias modes:
(a) Divertor probes in sweep and Vf mode with gated fast sampling
(b) Divertor probes in Isat and Vf mode with continuous fast sampling

Starting Discharge:
1 MA, 5.1 tesla, Ohmic, > 1.5 cm gaps, with optimized FSP Target.
Start from 990824002 with outer gap and inner gaps increased to 1.5 cm

Shot plan:
1-2 NL04=1.0e20, setup target, gas, etc.
3-6 NL04=1.0e20, with 4-shot sequence:
I - FSP/ASP/FMP in (a) bias mode, "shallow" FSP/ASP insertion with C2H4 plumes, CIII filters
II - FSP/ASP/FMP in (b) bias mode, "shallow" FSP/ASP insertion with C2H4 plumes, CII filters
III - FSP/ASP/FMP in (a) bias mode, "deep" FSP/ASP insertion with C2H4 plumes, CIII filters
IV - FSP/ASP/FMP in (b) bias mode, "deep" FSP/ASP insertion with C2H4 plumes, CII filters
7-10 NL04=0.6e20, repeat 4-shot sequence
11-14 NL04=1.4e20, repeat 4-shot sequence
15-16 NL04=1.0e20, Ip = 1.2 MA, do sequence III,IV
17-18 NL04=1.0e20, Ip = 0.8 MA, do sequence III,IV
================================================================================

Results:

Discharges for MP#208 were executed almost according to
plan. We found that for some reason Mach data taken during the NL04=0.6e20 sequence
did not exhibit the usual reversed parallel flows in the SOL. Perhaps the
FSP was not inserted deep enough. Consequently, we dropped the Ip scan and instead
went to a series of 4 shots with NL04=0.85e20 and deep FSP insertion. Reversed
flows were seen and plumes exhibited a corresponding parallel shift away from the divertor.
Good CII and CIII plumes were seen on most of the shots. From analysis of
the difference in CII and CIII emission patterns, we hope to learn something about
the cross-field and parallel transport of impurity ions in the SOL. Hopefully,
these data will be an important part of Sanjay's doctoral thesis.

Actual Shot summary:

shot NL04 Plume Location Filter Probe Bias Mode Comment
1 1.0 moderate CIII Mach FSP-camera timing is off, dithering
2 1.0 deep CIII Mach ok plumes, dithering
3 1.0 deep CII Fluctuation Nice plumes, dithering
4 1.0 shallow CIII Mach Nice Plumes, dithering
5 1.0 shallow CIII Fluctuation Nice Plumes, dithering
6 0.7 shallow CIII Mach FSP had trouble scanning!
7 0.7 shallow CIII Mach FSP scanned OK. CIII plumes too weak
8 0.7 shallow CIII Mach Plumes OK, still a bit weak
9 0.7 shallow CII Fluctuation Plumes ok
10 0.7 deep CIII Mach Plumes look good
11 0.7 deep CII Fluctuation Plumes look good
12 1.3 shallow CIII Mach Plumes are saturated
13 1.3 shallow CIII Mach One good plume, disrupts at 0.61 sec
14 fizzle
15 1.3 shallow CIII Mach Plumes look good
16 1.3 shallow CII Fluctuation Plumes look good, narrow poloidal extent
17 1.3 deep CIII Mach Small extent CIII plumes
18 1.3 deep CII Fluctuation Plumes are tiny
19 0.85 shallow CIII Mach Good plumes, dithering on third scan
20 0.85 shallow CII Fluctuation Plumes are OK, Argon enabled, still dithering on third scan
21 0.85 deep CIII Mach Plumes are OK, Argon enabled, still dithering on third scan
22 0.85 deep CII Fluctuation Plumes are OK, Argon enabled, still dithering on third scan


================================================================================
Second half run plan:
================================================================================
SOL Transport MP#228

Objectives:

Record cross-field SOL profiles of density, Te, // flow, and fluctuations in
ohmic H-mode discharges with different end of shot 'flat-top' Bt but roughly
the same qPsi95.

Setup:
FSP: - Operate in two bias modes:
(a) West/East-sweep, North/South-float mode
(b) West/South-sweep, North/East-float mode
- Enable gas (C2H4) for optional plumes
- Set up for a "deep" scan to the separatrix

ASP: - Operate in two bias modes: (South probe is dead)
(a) West/East-sweep, North-float mode
(b) West-sweep, North/East-float mode
- Set up for a "deep" scan to the separatrix

FMP: - Operate in two bias modes:
(a) Divertor probes in sweep and Vf mode with gated fast sampling
(b) Divertor probes in Isat and Vf mode with continuous fast sampling
Set fast triggers to capture Ohmic H-mode phase.

Starting Discharge:
Reload segment 3 (which is presently a modified version of segment 3 from
shot# 990819001): 1 MA, Ohmic H-mode ending with Bt at 5 tesla

Shot plan:
19-20 setup discharge and targeting
21-22 FSP/ASP/FMP in bias mode (a) then (b)
23 Change end point Bt to 3.5 tesla, Ip = 0.7 MA.
24-25 FSP/ASP/FMP in bias mode (a) then (b)
26 Change end point Bt to 6.0 tesla, Ip = 1.2 MA.
27-28 FSP/ASP/FMP in bias mode (a) then (b)
================================================================================

Result:
No discharges run.

Physics Operator Summaries
Entered: Jul 7 2004 04:37:08:600PM
Author: To Be Determined
Engineering setup and run plan for Wednesday 25 August 1999

MP#208/228 Plumes and SOL Transport
SL: B. LaBombard and S. Gangadhara
PO: J. Snipes

Run will begin at 9:00AM and end at 5:00PM.

For the plume studies, start with standard 1MA 5.1T plasmas (like 990824002).
Run four identical shots to scan the FSP together with different carbon filters
viewing the probe. Then, the density will be scanned from nl04 = 0.6 x 10^20
m^-2 to 1.4 x 10^20 m^-2 in separate series of similar shots.

For the SOL Transport studies, we will use ohmic H-mode discharges like
990819001 to start with. Then, we will vary the toroidal field at the end of
the H-mode to perform a TF scan in H-mode from 3 T to 6 T. We will raise or
lower the current to maintain the H-mode over this range of toroidal fields
staying at nearly constant q95 at the end of the H-mode to avoid low q
disruptions.

Engineering setup:
*** Two hours of ECDC in D2 prior to the run. ***


Setup power supplies from 990824002

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 6 psi of H2 Hybrid DISABLED
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bottom as is Hybrid DISABLED

The following gate valves should be enabled, assuming no vacuum problems:
ECE, VUV

Summary: It was a very good run. The machine ran very well with only a slight
delay to investigate an intermittent problem with EFC whereby the static
voltage reached only 700 V and drooped to 500 V instead of reaching 1000 V and
drooping to 700 V as it usually does. The problem went away on the next shot.
Only the MP 208 Plume studies was accomplished because it really was asking too
much to do two mini-proposals in one day. With 4 good shots required for
shallow and deep probe insertion with CII and CIII filters and proper camera
exposure, we were able to scan 4 different densities and got good data for all
conditions. The current scan was not attempted in favor of an intermediate
density point. The RF also managed to get in some conditioning late in the
discharge and they were able to get into H-mode with low power on both E and J
port antennas. On the last shot, the RF managed to combine J3, J4, and E port
antennas to reach 2 MW peak and got a nice H-mode at the end of the discharge.
Some fluctuations were observed on the PCI and reflectometer that appear to be
at the same frequency during H-mode. They were not present on the magnetics.
Of 22 shots, only one was a fizzle (though not by Ian's program, see below),
which was probably due to overcooling because of a one hour delay to check out
the EFC power supply. One shot disrupted at 0.6 sec perhaps due to the EFC
problem. The other 20 shots were full length 1 MA plasmas many of which ramped
down past 1.8 sec due to a change in RCUR in the rampdown.

Shot 1: Copied shot 990824002, then dropped nl04 from 1.1 to 1.0 x 10^20 m^-2.
Reduced RCUR by 4 mm until 1.2 sec, then shifted it back out so that we
should have 1.5 cm inner and outer gaps until 1.2 sec, then decrease
the gap to 1 cm. Good shot!
Shot 2: Changed RCUR slightly after 1.2 sec to increase outer gap to 1.2 cm
for the RF at the end of the shot. Good shot!
Shot 3: Repeat. Good shot.
Shot 4: Repeat. Good shot.
Shot 5: Repeat. Good shot.
Shot 6: Reducing nl04 to 0.6 x 10^20 m^-2. Good shot!
Shot 7: Changed nl04 to 0.7 x 10^20 m^-2 to try to ensure the same density for
the next shot. Good shot. Br jumped down by 1 mT. RF between 1.2
and 1.4 sec from 0.2 to 0.3 MW. H-mode during RF becoming EDA in
the rampdown.
Shot 8: Increased Br0 by 0.5 mT to 0 mT. Good shot. Again, RF H-mode at the
end of the shot.
Shot 9: Repeat. Good shot. Disrupted at 1.4 sec due to a large impurity
injection just as the RF shuts off in H-mode.
Shot 10: Repeat without RF. Good shot. Spectroscopy tree corrupted. No
spectroscopy data for this shot!
Shot 11: Repeat. Good shot.
Shot 12: Raising nl04 to 1.4 x 10^20 m^-2. Good shot. Achieved 1.3 x 10^20
m^-2.
Shot 13: Reduced nl04 to 1.3 x 10^20 m^-3 to try to keep the density there.
Kept RCUR out at 0.669 m after 1.4 sec to try to avoid the disruption
at 1.6 sec. It may also be due to the change in the RCUR offset from
8000 to 5000 at 1.6 sec. Disrupted violently at 0.61 sec. Appears
to have gone vertically unstable. The static voltage on the EFC
supply drooped to 500 V instead of its usual 700 V, which may have
helped lead to the disruption. Brief pause to look at the EFC power
supply.
Shot 14: Try again after some changes to the EFC supply. Fizzle!
Shot 15: Reduced Br0 back to -0.5 mT from 0 mT. Good shot.
Shot 16: Adjusted RCUR slightly at 1.22 sec to try to keep the gap at 1.2 cm
for the RF between 1.22 and 1.4 sec. LN2 leaking onto the floor in
the cell from the cryostat. Good shot.
Shot 17: Repeat. Good shot.
Shot 18: Repeat. Good shot.
Shot 19: Reduce nl04 to 7.5 x 10^19 m^-2 to try to get 8 x 10^19 m^-2.
Good shot. Got 8.5 x 10^19 m^-2.
Shot 20: Program nl04 to 8.5 x 10^19 m^-2 to keep it there. Enable Ar puff at
0.3 sec for 33 msec to attempt to eliminate the dithering by raising
the H-mode threshold with impurities. Good shot. H-mode in rampdown
driven by E port. Shot 19 without Ar got H-mode with J4 only.
Shot 21: Repeat. Good shot.
Shot 22: Repeat to get the last point with CII filter. Good shot. Good run!
Nice H-mode at the end of the flattop and into the rampdown with J3,
J4, and E port RF all together up to 2 MW peak.
Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax
1 1.765 0.982 2 1.755 0.977
3 1.747 0.982 4 1.737 0.977
5 1.753 0.977 6 1.764 0.987
7 1.772 0.987 8 1.762 0.987
9 1.418 0.987 10 1.767 0.987
11 1.766 0.987 12 1.612 0.977
13 0.616 1.018 14 0.000 0.052
15 1.840 0.987 16 1.830 0.977
17 1.810 0.977 18 1.820 0.977
19 1.860 0.987 20 1.850 0.987
21 1.850 0.987 22 1.860 0.985

Finished summary for 990825 Total of 22 shots.
22 shots. 22 plasmas. 0 fizzles. 0 duds.
Fizzle = gt 27.0 lt 50kA.

Session Leader Comments
Aug 25 1999 08:52:48:483AMBrian LabombardPPPL and LANL cameras synchronized this morning
C2H4 test injection before run recorded as shot#6095 in edge tree
Aug 25 1999 09:30:38:060AM990825001Brian LabombardFSP/ASP scanning with C2H4 injection
A2 bias setup ("deep" Mach mode, gated divertor probes)
Timing slightly off on FSP scans.

Next shot, repeat with deeper probes
Aug 25 1999 09:46:46:293AM990825002Brian LabombardFSP/ASP scanning with C2H4 injection
A2 bias setup ("deep" Mach mode, gated divertor probes)
Timing is better on FSP scans.

Next shot, repeat with CII filter.
Aug 25 1999 10:12:11:263AM990825003Brian LabombardFSP/ASP scanning with C2H4 injection
B2 bias setup ("deep" fluctuation mode, non-gated divertor probes)
Nice plumes.

Next shot, repeat with shallow injection, A10 bias and CIII filters.
Aug 25 1999 10:22:17:373AM990825004Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
Nice plumes

Next shot, repeat with shallow injection, B10 bias and CII filters
Aug 25 1999 10:37:50:340AM990825005Brian LabombardFSP/ASP scanning with C2H4 injection
B10 bias setup ("shallow" fluctuation mode, non-gated divertor probes)
Nice plumes

Next shot, go to NL04=0.6 with shallow injection, A10 bias and CIII filters
Aug 25 1999 10:59:20:733AM990825006Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)

FSP had trouble scanning!

Next shot, repeat with no changes.
Aug 25 1999 11:17:35:920AM990825007Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)

FSP scanned OK but CIII plumes are very weak.

Next shot, repeat with increased exposure time.
Aug 25 1999 11:35:08:310AM990825008Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
OK plumes, a little weak

Next shot repeat and go to B10 bias, CII filters and shallow scan.
Aug 25 1999 11:56:46:810AM990825009Brian LabombardFSP/ASP scanning with C2H4 injection
B10 bias setup ("shallow" fluctuation mode, non-gated divertor probes)
CII plumes are ok

Next shot repeat and go to A2 bias and CIII filters with deep scan
Aug 25 1999 12:13:51:483PM990825010Brian LabombardFSP/ASP scanning with C2H4 injection
A2 bias setup ("deep" Mach mode, gated divertor probes)
CIII plumes look good

Next shot repeat and go to A2 bias with CII filters with deep scan
Aug 25 1999 12:30:36:920PM990825011Brian LabombardFSP/ASP scanning with C2H4 injection
B10 bias setup ("shallow" fluctuation mode, non-gated divertor probes)
CII plumes look good

Next shot go to NL04=1.4 with A10 bias, shallow insertion, CIII filters
Aug 25 1999 12:50:18:293PM990825012Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
CIII plumes are saturated

Next shot: Repeat with shorter camera exposures
Aug 25 1999 01:23:38:860PM990825013Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
First CIII plume looks good. Shot disrupted at .61 sec

Next shot: Repeat
Aug 25 1999 02:47:08:687PM990825015Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
Plumes look good.

Next shot: repeat, go to B10 bias, shallow injection with CII filter
Aug 25 1999 03:14:14:153PM990825016Brian LabombardFSP/ASP scanning with C2H4 injection
B10 bias setup ("shallow" fluctuation mode, non-gated divertor probes)
Plumes look good (narrow poloidal extent)

Next shot: repeat, go to A2 Bias, deep insertion, CIII filters.
Aug 25 1999 03:31:34:903PM990825017Brian LabombardFSP/ASP scanning with C2H4 injection
A2 bias setup ("deep" Mach mode, gated divertor probes)
Small extent CIII plumes.

Next shot: repeat, go to B2 bias, deep insertion, CII filters

Aug 25 1999 03:47:57:640PM990825018Brian LabombardFSP/ASP scanning with C2H4 injection
B2 bias setup ("deep" fluctuation mode, non-gated divertor probes)
CII plumes are tiny.

Next shot: go to NL04=0.85 with A10 bias, shallow insertion, CIII filters

Aug 25 1999 04:07:53:437PM990825019Brian LabombardFSP/ASP scanning with C2H4 injection
A10 bias setup ("shallow" Mach mode, gated divertor probes)
CIII plumes look good. Dithering on third scan.

Next shot: Repeat with Argon enabled, B10 bias, shallow insertion, CII filters
Aug 25 1999 04:23:41:983PM990825020Brian LabombardFSP/ASP scanning with C2H4 injection
B10 bias setup ("shallow" fluctuation mode, non-gated divertor probes)
CII plumes are ok.

Next shot: Repeat with Argon enabled, A2 bias, deep insertion, CIII filters
Aug 25 1999 04:57:51:090PM990825021Brian LabombardFSP/ASP scanning with C2H4 injection
A2 bias setup ("deep" Mach mode, gated divertor probes)
Good CIII plumes.

Next shot: Repeat with Argon enabled, B2 bias, deep injection, CII filter

Physics Operator Comments
Aug 25 1999 08:28:56:327AMJoseph SnipesEngineering setup and run plan for Wednesday 25 August 1999

MP#208/228 Plumes and SOL Transport
SL: B. LaBombard and S. Gangadhara
PO: J. Snipes

Run will begin at 9:00AM and end at 5:00PM.

For the plume studies, start with standard 1MA 5.1T plasmas (like 990824002).
Run four identical shots to scan the FSP together with different carbon filters
viewing the probe. Then, the density will be scanned from nl04 = 0.6 x 10^20
m^-2 to 1.4 x 10^20 m^-2 in separate series of similar shots.

For the SOL Transport studies, we will use ohmic H-mode discharges like
990819001 to start with. Then, we will vary the toroidal field at the end of
the H-mode to perform a TF scan in H-mode from 3 T to 6 T. We will raise or
lower the current to maintain the H-mode over this range of toroidal fields
staying at nearly constant q95 at the end of the H-mode to avoid low q
disruptions.

Engineering setup:
*** Two hours of ECDC in D2 prior to the run. ***


Setup power supplies from 990824002

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid DISABLED
fill B-side upper with 6 psi of H2 Hybrid DISABLED
fill C-side with 30 psi of D2 Hybrid enabled
leave J-bottom as is Hybrid DISABLED

The following gate valves should be enabled, assuming no vacuum problems:
ECE, VUV

Aug 25 1999 09:23:19:293AM990825001Joseph SnipesShot 1: Copied shot 990824002, then dropped nl04 from 1.1 to 1.0 x 10^20 m^-2.
Reduced RCUR by 4 mm until 1.2 sec, then shifted it back out so that we
should have 1.5 cm inner and outer gaps until 1.2 sec, then decrease
the gap to 1 cm. Good shot!
Aug 25 1999 09:45:53:687AM990825002Joseph SnipesShot 2: Changed RCUR slightly after 1.2 sec to increase outer gap to 1.2 cm
for the RF at the end of the shot. Good shot!
Aug 25 1999 09:57:26:577AM990825003Joseph SnipesShot 3: Repeat. Good shot.
Aug 25 1999 10:15:38:140AM990825004Joseph SnipesShot 4: Repeat. Good shot.
Aug 25 1999 10:32:47:687AM990825005Joseph SnipesShot 5: Repeat. Good shot.
Aug 25 1999 10:49:47:607AM990825006Joseph SnipesShot 6: Reducing nl04 to 0.6 x 10^20 m^-2. Good shot!
Aug 25 1999 11:15:01:467AM990825007Joseph SnipesShot 7: Changed nl04 to 0.7 x 10^20 m^-2 to try to ensure the same density for
the next shot. Good shot. Br jumped down by 1 mT.
Aug 25 1999 11:21:46:263AM990825007Joseph SnipesShot 7: RF between 1.2 and 1.4 sec from 0.2 to 0.3 MW. H-mode during RF
becoming EDA in the rampdown.
Aug 25 1999 11:51:49:200AM990825008Joseph SnipesShot 8: Increased Br0 by 0.5 mT to 0 mT. Good shot. Again, RF H-mode at the
end of the shot.
Aug 25 1999 11:52:57:670AM990825009Joseph SnipesShot 9: Repeat. Good shot. Disrupted at 1.4 sec due to a large impurity
injection just as the RF shuts off in H-mode.
Aug 25 1999 12:10:35:107PM990825010Joseph SnipesShot 10: Repeat without RF. Good shot. Spectroscopy tree corrupted. No
spectroscopy data for this shot!
Aug 25 1999 12:30:32:983PM990825011Joseph SnipesShot 11: Repeat. Good shot.
Aug 25 1999 12:47:33:560PM990825012Joseph SnipesShot 12: Raising nl04 to 1.4 x 10^20 m^-2. Good shot. Achieved 1.3 x 10^20
m^-2.
Aug 25 1999 01:28:10:013PM990825013Joseph SnipesShot 13: Reduced nl04 to 1.3 x 10^20 m^-3 to try to keep the density there.
Kept RCUR out at 0.669 m after 1.4 sec to try to avoid the disruption
at 1.6 sec. It may also be due to the change in the RCUR offset from
8000 to 5000 at 1.6 sec. Disrupted violently at 0.61 sec. Appears to
have gone vertically unstable.
Aug 25 1999 01:45:24:903PM990825013Joseph SnipesShot 13: The static voltage on the EFC supply drooped to 500 V instead of its
usual 700 V, which may have helped lead to the disruption. Brief
pause to look at the EFC power supply.
Aug 25 1999 02:31:11:640PM990825014Joseph SnipesShot 14: Try again after some changes to the EFC supply. Fizzle!
Aug 25 1999 02:45:34:060PM990825015Joseph SnipesShot 15: Reduced Br0 back to -0.5 mT from 0 mT. Good shot.
Aug 25 1999 03:04:06:513PM990825016Joseph SnipesShot 16: Adjusted RCUR slightly at 1.22 sec to try to keep the gap at 1.2 cm
for the RF between 1.22 and 1.4 sec. LN2 leaking onto the floor in the
cell from the cryostat. Good shot.
Aug 25 1999 03:23:41:747PM990825017Joseph SnipesShot 17: Repeat. Good shot.
Aug 25 1999 03:43:52:090PM990825018Joseph SnipesShot 18: Repeat. Good shot.
Aug 25 1999 04:07:17:453PM990825019Joseph SnipesShot 19: Reduce nl04 to 7.5 x 10^19 m^-2 to try to get 8 x 10^19 m^-2.
Good shot. Got 8.5 x 10^19 m^-2.
Aug 25 1999 04:31:00:310PM990825020Joseph SnipesShot 20: Program nl04 to 8.5 x 10^19 m^-2 to keep it there. Enable Ar puff at
0.3 sec for 33 msec to attempt to eliminate the dithering by raising
the H-mode threshold with impurities. Good shot. H-mode in rampdown
driven by E port. Shot 19 without Ar got H-mode with J4 only.
Aug 25 1999 04:53:20:263PM990825021Joseph SnipesShot 21: Repeat. Good shot.
Aug 25 1999 05:10:09:687PM990825022Joseph SnipesShot 22: Repeat to get the last point with CII filter. Good shot. Good run!
Aug 25 1999 05:14:10:420PM990825022Joseph SnipesShot 22: Nice H-mode at the end of the flattop and into the rampdown with J3,
J4, and E port RF all together up to 2 MW peak.
Aug 25 1999 05:16:59:293PM990825022Joseph Snipes Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax
1 1.765 0.982 2 1.755 0.977
3 1.747 0.982 4 1.737 0.977
5 1.753 0.977 6 1.764 0.987
7 1.772 0.987 8 1.762 0.987
9 1.418 0.987 10 1.767 0.987
11 1.766 0.987 12 1.612 0.977
13 0.616 1.018 14 0.000 0.052
15 1.840 0.987 16 1.830 0.977
17 1.810 0.977 18 1.820 0.977
19 1.860 0.987 20 1.850 0.987
21 1.850 0.987 22 1.860 0.985

Finished summary for 990825 Total of 22 shots.
22 shots. 22 plasmas. 0 fizzles. 0 duds.
Fizzle = gt 27.0 lt 50kA.
To print to file: unit=2; openw,unit,'file',/stream; .run summary; close,unit
To plot currents, set iplot=1. Adjust ncols, nrows if nec.
Aug 25 1999 05:30:27:687PM990825022Joseph SnipesSummary: It was a very good run. The machine ran very well with only a slight
delay to investigate an intermittent problem with EFC whereby the static
voltage reached only 700 V and drooped to 500 V instead of reaching 1000 V and
drooping to 700 V as it usually does. The problem went away on the next shot.
Only the MP 208 Plume studies was accomplished because it really was asking too
much to do two mini-proposals in one day. With 4 good shots required for
shallow and deep probe insertion with CII and CIII filters and proper camera
exposure, we were able to scan 4 different densities and got good data for all
conditions. The current scan was not attempted in favor of an intermediate
density point. The RF also managed to get in some conditioning late in the
discharge and they were able to get into H-mode with low power on both E and J
port antennas. On the last shot, the RF managed to combine J3, J4, and E port
antennas to reach 2 MW peak and got a nice H-mode at the end of the discharge.
Some fluctuations were observed on the PCI and reflectometer that appear to be
at the same frequency during H-mode. They were not present on the magnetics.
Of 22 shots, only one was a fizzle (though not by Ian's program, see below),
which was probably due to overcooling because of a one hour delay to check out
the EFC power supply. One shot disrupted at 0.6 sec perhaps due to the EFC
problem. The other 20 shots were full length 1 MA plasmas many of which ramped
down past 1.8 sec due to a change in RCUR in the rampdown.
Aug 26 1999 12:19:00:763PM990825022Ron Parker
SHOT 990826001

SHOT WAS PROGRAMMED TO REPRODUCE SHOT 990824002, WHICH IT DID.

THERE WAS NO RF ON THIS SHOT. RF CONDITIONING WILL BEGIN ON NEXT SHOT.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:20:54:513AMPlasmaOk(null)
209:38:31:513AMPlasmaOk(null)
309:55:52:297AMPlasmaOk(null)
410:13:49:747AMPlasmaOk(null)
510:31:12:967AMPlasmaOk(null)
610:48:07:640AMPlasmaOk(null)
711:10:35:967AMPlasmaOk(null)
811:28:32:827AMPlasmaOk(null)
911:47:27:623AMPlasmaOk(null)
1012:05:00:840PMPlasmaOk(null)
1112:24:18:717PMPlasmaOk(null)
1212:41:46:263PMPlasmaOk(null)
1301:13:46:653PMPlasmaOk(null)
1402:23:39:420PMPlasmaOk(null)
1502:40:56:157PMPlasmaOk(null)
1603:02:41:810PMPlasmaOk(null)
1703:21:32:950PMPlasmaOk(null)
1803:41:59:060PMPlasmaOk(null)
1904:00:10:030PMPlasmaOk(null)
2004:18:42:857PMPlasmaOk(null)
2104:49:54:657PMPlasmaOk(null)
2205:05:42:793PMPlasmaOk(null)