Alcator C-Mod Run 1030603 Information

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Miniproposals
Miniproposal:332
Date Filed: 4/8/2003
Title:A new approach to the study of turbulent edge plasma fluctuations.
First Author:Olaf Grulke
Session Leader:Robert Granetz (shots 1-21)

Operators
Session leader(s):Robert Granetz
Physics operator(s):Robert Granetz
Engineering operator(s):Gary Dekow,Bill Parkin,Ed Fitzgerald

Engineering Operator Run Comment
Purpose; MP332 - New Approach To The Study Of Turbulent Edge Plasma/Grul

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:32:833PM
Author: Robert Granetz
-------------------------------------------------------------------------------
Engineering setup for Tuesday, 03 June 2003

Purpose: MP 332 - New approach to study of turbulent edge plasma
fluctuations
MP 330 - Edge minority heating for H-mode control
and boronization recovery

Session leader: Grulke, Zweben, Terry
Physics operator: R. Granetz

ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00.
Bake at 60 C overnight as well, if possible.

Run begins at 09:00 and ends at 17:00.

Power systems the same as on 1030502025 (0.8 MA, 5.4 T, lower single null)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Enable the following gate valves, assuming no vacuum problems:
ECE, DNB

-------------------------------------------------------------------------------
RF Setup: All 4 transmitters in Run On by 08:00.
-------------------------------------------------------------------------------

Run Plan: The first half of the day will be devoted to MP 332 and to
boronization recovery of the antennas. The 2nd half will be devoted
to MP 330 (vary Btor to change RF resonance location from core to edges)

001 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.15] sec
E: 0.75 MW [.6-1.15] sec
J: 1. MW [.6-1.15] sec
Result: NTP (no target plasma)
002 cycle test
003 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.15] sec
E: 0.75 MW [.6-1.15] sec
J: 1. MW [.6-1.15] sec
Result: plasma.
D: max faults
E: max faults
J: faults
004 NTP
005 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.15] sec
E: 0.75 MW [.6-1.15] sec
J: 1. MW [.6-1.15] sec
Result: plasma.
D: max faults - poor match
E: max faults - arcing
J: max faults - poor match on J4
006 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1.0 MW [.6-1.1] sec
Result: NTP
007 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
008 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: plasma.
D: max faults - better match
E: max faults - arcing
J: max faults - just missed match on J4
009 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
010 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
011 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
012 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: plasma.
D: max faults - better match
E: max faults - arcing
J: max faults -
013 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP

noticed that the phase was nearly 180deg off because we removed
a delay line from J4

changed the phase shifter to 210deg

014 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
015 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: plasma.
D: max faults
E: max faults
J: max faults - still mismatched
016 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
017 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
018 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
019 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
020 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: NTP
021 Ip~0.8 MA, 5.4 T, nl~0.5 LSN
D: 0.75 MW [.6-1.1] sec
E: 0.75 MW [.6-1.1] sec
J: 1. MW [.6-1.1] sec
Result: plasma.
D: max faults
E: max faults
J: max faults - still mismatched

Run summary:

Appear to have improved the phase lock time by removing a short cable
from J4. The collatoral problem was that the phase between J3 and J4
changed to nearly 0 phase. Discharges were required to change the
phase back to heating phase and made tuning difficult for J-port.
J-port vacuum conditioning was better than after the last boronization
(same as last campaign). The antenna quickly conditioned to ~32 kv.

Entered: Jul 7 2004 03:49:32:850PM
Author: Robert Granetz
This run has been split between MP 332 (morning - piggy back) and MP 330a (afternoon).
This report addresses the MP 332 piggyback part of the experiment and the MP 330a part
of the experiment.

For the MP 332 part ---------------------------------------------------------------

We desire to find experimentally at which field and current the F-probe magnetically
maps to the observation region of the GPI system. This is in order to make a
simultaneous spatiotemporal measurement of plasma density and plasma potential
fluctuations.

The mapping should occur at B_t=5.4 T and I_p between 570 and 630 kA. We will plunge the probe
at currents of 570kA, 585 kA, 600 kA, 615kA, and 630kA and look at the
cross-correlation between I-sat and V-floating signals
on the probe and the light fluctuations on the radial array of GPI views.


On this day 1030603 only 2 different current values could be tested:

# 1030603008: 600kA (time of probe plunge maximum=1.3 and 1.5 s; diode data @300kHz)
# 1030603021: 590kA (time of probe plunge maximum=1.25 s; diode data @300kHz)

The efit reconstruction shows clear mapping and a significant correlation
between the F-probe data and the diode data was found, mainly consistent with
the calculations. Shots for the other proposed current values are re-scheduled
for 06.04.2003.


On 1030604 we continued the piggyback turbulence mapping experiments of
06-03-2003. The plasma currents were varied between 590-640kA in 8 successful
shots:

# 1030604005: I_p=600kA (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604006: I_p=600kA, slightly lower density (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604007: I_p=590kA (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604009: I_p=590kA (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604010: I_p=620kA (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604014: I_p=620kA, density raised to nl=1.2e20 (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604016: I_p=610kA, density decreased to nl=1e20 (time of probe plunge maximum=1.25 s; diode data @1 MHz)
# 1030604017: I_p=640kA (time of probe plunge maximum=1.25 s; diode data @1 MHz)



RESULTS:

1. Correlation analysis shows a typical correlation between F-probe and diode
data of 25-30%, which is clearly above the noise level. The higher correlation values were
with the floating potential signals while the 0.25 value was for correlations with I_sat.
The noise level of the correlation was typically <0.1.

2. For different plasma currents the correlation was found generally in agreement
with the respective efit calculations. Typically an "above-noise" correlation
was seen on ~3 diode views, centered on the view consistent with the EFIT mapping.

3. A localized influence of the F-probe was clearly visible in the diode raw data and
indications are also observed in the PSI camera images.

4. An increase in density from nl=1e20 to nl=1.2e20 seems to decrease the
correlation.


Physics Operator Summaries
Entered: Jul 7 2004 04:37:18:067PM
Author: Robert Granetz
Physics operator summary for run 1030603 (Tuesday):

Boronization recovery
MP 332 - New approach to study of turbulent edge plasma fluctuations
MP 330 - Edge minority heating for H-mode control

Session leader: O. Grulke, S. Zweben, J. Terry
Physics operator: R. Granetz
Engineers in charge: G. Dekow/E. Fitzgerald/W. Parkin

Summary: We certainly did not recover from the weekend's boronization. The
latter half of the day had only a 32% success rate. We tried
varying the pre-fill pressure, increasing Br0, and between-shot
ECDC, all to no avail. Let's hope that a night of ECDC will turn
things around. The first half of the day was lost due to an
MDSplus software problem, which cropped up after the mdstreeshr.so
was modified prior to today's run. This corrupted the data in the
hybrid tree, with subsequent failure of hybrid control. We barely
got a start on MP 332, with two values of the current plateau.

Scorecard: 6 plasmas
13 fizzles
1 duds (MDSplus software problem)
1 test or no-power shot cycle
0 aborted and/or screwed up by computer problems
----------
21 total

-------------------------------------------------------------------------------

Engineering setup for Tuesday, 03 June 2003

Purpose: MP 332 - New approach to study of turbulent edge plasma fluctuations
MP 330 - Edge minority heating for H-mode control
and boronization recovery

Session leader: Grulke, Zweben, Terry
Physics operator: R. Granetz

ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00.
Bake at 60 C overnight as well, if possible.

Run begins at 09:00 and ends at 17:00.

Power systems the same as on 1030502025 (0.8 MA, 5.4 T, lower single null)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Enable the following gate valves, assuming no vacuum problems:
ECE, DNB

-------------------------------------------------------------------------------
RF Setup: All 4 transmitters in Run On by 08:00.

-------------------------------------------------------------------------------

Run Plan: The first half of the day will be devoted to MP 332 and to
boronization recovery of the antennas. The 2nd half will be devoted
to MP 330 (vary Btor to change RF resonance location from core to edges)

-------------------------------------------------------------------------------

ECDC was done overnight, as well as a 60 C bake.

Hybrid coldstart done by the engineering group; no errors found

Tried to load PCS segment 2 from shot 1030502025 (0.8 MA, 5.4 T,
single null lower), segment 1 from shot 1030530034 (last shot from
last Friday). Then I adjusted the nl_04 up to 1.e20 m-2, and
programmed in a rampdown of Ip down to a flattop of 630 kA for
250 ms from t=1.250 to 1.500 s. HOWEVER, PCS hung when I tried to
load the shot into model. I tried this several times, without
success. So Josh had to figure out the problem. (He made a small
modification to PCS yesterday, which shouldn't have caused this
problem.)

-------------------------------------------------------------------------------

Since the RF was firing into the vacuum chamber before the run began,
I requested 10 minutes of ECDC before the first plasma shot.


Start of run was delayed by 30 minutes due to PCS software bug.

Shot 01 -- Dud. Many power supplies failed to go in segment 1. Steve Wolfe
reports that the hybrid did not have any finite outputs in
segment 1. Problem with wavegen?

Steve did another coldstart and a hybrid test shot, and the
wavegen again failed to output anything.

We're having a long break while Steve and Josh work on the hybrid problem.

Steve, Tom, and Josh have concluded that this was a software problem which
arose because of an incorrect version of mdstreeshr.so that somehow became
the active version. (Tom and Josh were both working on MDS software since
the last run.)

Next shot: no-power test to make sure the wavegen puts out the
correct signals.

Shot 02 -- Test. Hybrid output looks good.

Next shot: go for plasma.

Shot 03 -- Plasma. Disrupted at t=1.28 s, during the rampdown to the plateau
level. Gaps increase around that time for some reason.

Next shot: start Ip plateau rampdown earlier to reduce demands on
PF supplies.

Shot 04 -- Fizzle.

Next shot: reduce pre-fill puff by 1 ms.

Shot 05 -- Plasma. Good shot. Plateau level is 590 kA (asked for 630 kA) for
0.25 s. NL_04=1.1e20 m-2. Startup is still ugly.

Next shot: increase plateau duration to 0.40 s by starting the
rampdown earlier, and increase plateau current by 10 kA.

Shot 06 -- Fizzle.

Next shot: reduce pre-fill puff by another 1 ms.

Shot 07 -- Fizzle.

Next shot: put the pre-fill back to the original value.

Shot 08 -- Plasma. Good shot. Plateau = 600 kA for 0.4 s. NL_04=1.2e20 m-2.
Ninja is puffing starting at t=1.1 s, and it can be seen on the
GHLIM video images. It also raises the density slightly.

Next shot: reduce programmed nl_04 to 0.9e20 m-2 (was 1.0e20 m-2).

Shot 09 -- Fizzle.

Next shot: no changes.

Shot 10 -- Fizzle.

Next shot: reduce pre-fill by 3 ms (to 24 ms)

Shot 11 -- Fizzle. Current rise was too fast this time.

Next shot: increase pre-fill by 1 ms.

Shot 12 -- Plasma. Good shot. Plateau = 610 kA for 0.4 s. NL_04=1.0e20 m-2.

Next shot: reduce Ip in plateau by 15 kA. Increase pre-fill
puff by another 1 ms.

Shot 13 -- Fizzle.

Next shot: no changes

Shot 14 -- Fizzle.

Next shot: no changes

Shot 15 -- Plasma. Good shot. Plateau = 590 kA. Still not a good startup.

Next shot: no changes

Shot 16 -- Fizzle.

Next shot: increase pre-fill by another 1 ms.

Shot 17 -- Fizzle.

Next shot: increase Br0 by 0.5 mT (Ian's suggestion), and ECDC for
a few minutes between shots.

Shot 18 -- Fizzle.

Next shot: reduce pre-fill by 2 ms.

Shot 19 -- Fizzle.

Next shot: take another 1 ms off the pre-fill

Shot 20 -- Fizzle.

Next shot: reload shot 15 (longer pre-fill; remove Br0 tweak)

Shot 21 -- Plasma. Good shot. Plateau current = 600 kA. Startup still
was bad.

End of run

Session Leader Comments

Physics Operator Comments
Jun 3 2003 09:14:28:780AMRobert Granetz
Engineering setup for Tuesday, 03 June 2003

Purpose: MP 332 - New approach to study of turbulent edge plasma fluctuations
MP 330 - Edge minority heating for H-mode control
and boronization recovery

Session leader: Grulke, Zweben, Terry
Physics operator: R. Granetz

ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00.
Bake at 60 C overnight as well, if possible.

Run begins at 09:00 and ends at 17:00.

Power systems the same as on 1030502025 (0.8 MA, 5.4 T, lower single null)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Enable the following gate valves, assuming no vacuum problems:
ECE, DNB

-------------------------------------------------------------------------------
RF Setup: All 4 transmitters in Run On by 08:00.

-------------------------------------------------------------------------------

Run Plan: The first half of the day will be devoted to MP 332 and to
boronization recovery of the antennas. The 2nd half will be devoted
to MP 330 (vary Btor to change RF resonance location from core to edges)
Jun 3 2003 09:14:42:170AMRobert Granetz ECDC was done overnight, as well as a 60 C bake.

Hybrid coldstart done by the engineering group; no errors found

Tried to load PCS segment 2 from shot 1030502025 (0.8 MA, 5.4 T,
single null lower), segment 1 from shot 1030530034 (last shot from
last Friday). Then I adjusted the nl_04 up to 1.e20 m-2, and
programmed in a rampdown of Ip down to a flattop of 630 kA for
250 ms from t=1.250 to 1.500 s. HOWEVER, PCS hung when I tried to
load the shot into model. I tried this several times, without
success. So Josh had to figure out the problem. (He made a small
modification to PCS yesterday, which shouldn't have caused this
problem.)
Jun 3 2003 10:48:22:273AM1030603001Robert GranetzShot 01 -- Dud. Many power supplies failed to go in segment 1. Steve Wolfe
reports that the hybrid did not have any finite outputs in
segment 1. Problem with wavegen?

Steve did another coldstart and a hybrid test shot, and the
wavegen again failed to output anything.
Jun 3 2003 10:48:34:493AM1030603001Robert GranetzWe're having a long break while Steve and Josh work on the hybrid problem.
Jun 3 2003 12:50:53:067PM1030603001Robert GranetzSteve, Tom, and Josh have concluded that this was a software problem which
arose because of an incorrect version of mdstreeshr.so that somehow became
the active version. (Tom and Josh were both working on MDS software since
the last run.)
Jun 3 2003 12:51:03:490PM1030603001Robert Granetz Next shot: no-power test to make sure the wavegen puts out the
correct signals.
Jun 3 2003 01:16:08:680PM1030603002Robert GranetzShot 02 -- Test. Hybrid output looks good.

Next shot: go for plasma.
Jun 3 2003 01:12:52:850PM1030603003Robert GranetzShot 03 -- Plasma. Disrupted at t=1.28 s, during the rampdown to the plateau
level. Gaps increase around that time for some reason.

Next shot: start Ip plateau rampdown earlier to reduce demands on
PF supplies.
Jun 3 2003 01:15:33:303PM1030603004Robert GranetzShot 04 -- Fizzle.

Next shot: reduce pre-fill puff by 1 ms.
Jun 3 2003 01:32:57:520PM1030603005Robert GranetzShot 05 -- Plasma. Good shot. Plateau level is 590 kA (asked for 630 kA) for
0.25 s. NL_04=1.1e20 m-2. Startup is still ugly.

Next shot: increase plateau duration to 0.40 s by starting the
rampdown earlier, and increase plateau current by 10 kA.
Jun 3 2003 01:39:15:870PM1030603006Robert GranetzShot 06 -- Fizzle.

Next shot: reduce pre-fill puff by another 1 ms.
Jun 3 2003 01:53:18:647PM1030603007Robert GranetzShot 07 -- Fizzle.

Next shot: put the pre-fill back to the original value.
Jun 3 2003 02:12:56:487PM1030603008Robert GranetzShot 08 -- Plasma. Good shot. Plateau = 600 kA for 0.4 s. NL_04=1.2e20 m-2.
Ninja is puffing starting at t=1.1 s, and it can be seen on the
GHLIM video images. It also raises the density slightly.

Next shot: reduce programmed nl_04 to 0.9e20 m-2 (was 1.0e20 m-2).
Jun 3 2003 02:20:32:447PM1030603009Robert GranetzShot 09 -- Fizzle.

Next shot: no changes.
Jun 3 2003 02:36:21:617PM1030603010Robert GranetzShot 10 -- Fizzle.

Next shot: reduce pre-fill by 3 ms (to 24 ms)
Jun 3 2003 03:04:04:230PM1030603011Robert GranetzShot 11 -- Fizzle. Current rise was too fast this time.

Next shot: increase pre-fill by 1 ms.
Jun 3 2003 03:04:15:420PM1030603012Robert GranetzShot 12 -- Plasma. Good shot. Plateau = 610 kA for 0.4 s. NL_04=1.0e20 m-2.

Next shot: reduce Ip in plateau by 15 kA. Increase pre-fill
puff by another 1 ms.
Jun 3 2003 03:13:15:707PM1030603013Robert GranetzShot 13 -- Fizzle.

Next shot: no changes
Jun 3 2003 03:28:29:407PM1030603014Robert GranetzShot 14 -- Fizzle.

Next shot: no changes
Jun 3 2003 03:39:05:990PM1030603015Robert GranetzShot 15 -- Plasma. Good shot. Plateau = 590 kA. Still not a good startup.

Next shot: no changes
Jun 3 2003 03:51:44:410PM1030603016Robert GranetzShot 16 -- Fizzle.

Next shot: increase pre-fill by another 1 ms.
Jun 3 2003 04:07:57:577PM1030603017Robert GranetzShot 17 -- Fizzle.

Next shot: increase Br0 by 0.5 mT (Ian's suggestion), and ECDC for
a few minutes between shots.
Jun 3 2003 04:24:04:010PM1030603018Robert GranetzShot 18 -- Fizzle.

Next shot: reduce pre-fill by 2 ms.
Jun 3 2003 04:35:41:287PM1030603019Robert GranetzShot 19 -- Fizzle.

Next shot: take another 1 ms off the pre-fill
Jun 3 2003 05:01:03:850PM1030603020Robert GranetzShot 20 -- Fizzle.

Next shot: reload shot 15 (longer pre-fill; remove Br0 tweak)
Jun 3 2003 05:02:23:120PM1030603021Robert GranetzShot 21 -- Plasma. Good shot. Plateau current = 600 kA. Startup still
was bad.

End of run

Engineering Operator Comments
ShotTimeTypeStatusComment
109:35:57:910AMPlasmaBadData System Problems with Hybrid Outputs to Power Supplies
212:49:38:520PMTestOk
312:57:48:150PMPlasmaOk
401:10:27:533PMPlasmaOk
501:22:50:870PMPlasmaOk
601:35:09:473PMPlasmaOk
701:47:41:580PMPlasmaOk
802:01:40:480PMPlasmaOk
902:16:03:960PMPlasmaOk
1002:28:38:627PMPlasmaOk
1102:41:20:277PMPlasmaOk
1202:54:08:660PMPlasmaOk
1303:09:20:940PMPlasmaOk
1403:22:01:010PMPlasmaOk
1503:34:34:410PMPlasmaOk
1603:47:58:920PMPlasmaOk
1704:00:35:713PMPlasmaOk
1804:19:23:633PMPlasmaOk
1904:32:17:643PMPlasmaOk
2004:45:07:777PMPlasmaOk
2104:57:46:710PMPlasmaOk