Alcator C-Mod Run 1040421 Information

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Miniproposals
Miniproposal:203
Date Filed: 2/20/1998
Title:8 T H-mode Discharge Development with 3He Minority Heating
First Author:Steve Wukitch
Session Leader:Steve Wukitch (shots 1-13)

Operators
Session leader(s):Steve Wukitch
Physics operator(s):Earl Marmar
Engineering operator(s):Bill Cochran

Engineering Operator Run Comment
MP#203: 8T He3 Heating/Wukitch/Marmar/Cochran/Byford/Parkin

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:04:897PM
Author: Steve Wukitch
Engineering setup for Wednesday, 20 Apr 2004

MP#203: 8T He3 Heating

Session leader: Wukitch
Physics operator: Marmar

Overnight ECDC in D2 at 2e-4 Torr

Run begins at 08:00 and ends at 20:00.

Power systems the same as 1040407002 (1.0 MA, 5.4 T, lower X-point)

Once instrumentation has been checked we will load shot
1040407019 for 8T operation.

A-coils should be configured as on 1040409002 (+Dtop -Dbot -Jtop +Jbot)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
leave B-side upper with 15 psi He3 Hybrid enabled (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Disable NINJA

Enable the following gatevalves: ECE, VUV, DNB

Necessary diagnostics:
GPC2 set for 8 T, TCI, PCI, FRECE (5.4 T discharge)
McPherson/Chromex to monitor He3
halo current diagnostics, TF scanner
OH coax resistance and thermocouple instrumentation

-------------------------------------------------------------------------------
RF Setup: All four transmitters in RUN-ON by 07:30, all at 80 MHz
-------------------------------------------------------------------------------

Run Plan:

1. Scan He3 puff until MC is observed keeping the plasma out of H-mode by
using moderate RF power (~3.5 MW) Ip = 1.2 MA, BT~7.9 T, nl_04~0.85

2. Scan He3 where low MC was observed with high power (4.5 MW).

3. Scan density to optimize target for H-mode

4. Scan Ip to optimize target for H-mode

5. Scan antenna phase.
-------------------------------------------------------------------------------
001 5.4 T Ip~1 MA, nl_04~0.85
D: 1 MW ramp [1.1,1.5]sec
E: 1 MW ramp [1.1,1.5]sec
J: 2 MW ramp [0.6,1.]sec
result: plasma - phase +140
D: ran 2 faults
E: ran
J: ran 3 faults
next shot: 8 T, 1.2 MA
002 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma - TF crowbar, early disruption
D: ran max faults
E: ran max faults
J: ran
next shot: 50 kA TF test pulse

xbar prove appears flaky on FMIT#3
003 50 kA TF test pulse
004 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma - TF crowbar, early disruption
D: ran max faults
E: ran
J: ran 2 faults
next shot: 50 kA TF test pulse
005 50 kA TF test pulse
006 50 kA TF test pulse
007 5.2 T Ip~1 MA, nl_04~0.85
D: 1 MW ramp [1.1,1.5]sec
E: 1 MW ramp [1.1,1.5]sec
J: 2 MW ramp [0.6,1.]sec
result: plasma - phase +140
D: ran max faults
E: ran
J: ran without J3 - no gate
next shot: 8 T, 1.2 MA
008 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: -
E: -
J: -
result: plasma - TF crowbar
next shot: 50 kA TF test pulse
009 50 kA TF test pulse
010 TF test
011 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 30 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma
D: ran max faults
E: ran 2 faults
J: ran 5 faults - odd gate behavior on FMIT#4
012 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 30 msec
D: 0.8 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma
D: ran max faults
E: ran 6 faults
J: ran 2 faults
may be able to see break in slope on inner GPC2 channels at 0.9 sec
013 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 45 msec
D: 0.8 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma TF crowbar
D: ran 1 fault
E: ran 1 faults
J: ran 2 faults

Run summary

Although limited in shots, the 30 msec He3 puff appeared to show some
evidence of electron heating associated with mode conversion.
Additional He3 puff scan is still required to determine if the heating
moves further off axis as expected.

Physics Operator Summaries
Entered: Jul 7 2004 04:36:49:927PM
Author: Earl Marmar
Physop run summary, 1040421

MP#203: 8T He3 Heating

Session leader: Wukitch
Physics operator: Marmar

Overnight ECDC in D2 at 2e-4 Torr

Run begins at 08:00 and ends at 20:00.

Power systems the same as 1040407002 (1.0 MA, 5.4 T, lower X-point)

Once instrumentation has been checked we will load shot
1040407019 for 8T operation.

A-coils should be configured as on 1040409002 (+Dtop -Dbot -Jtop +Jbot)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
leave B-side upper with 15 psi He3 Hybrid enabled (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Disable NINJA

Enable the following gatevalves: ECE, VUV, DNB

Necessary diagnostics:
GPC2 set for 8 T, TCI, PCI, FRECE (5.4 T discharge)
McPherson/Chromex to monitor He3
halo current diagnostics, TF scanner
OH coax resistance and thermocouple instrumentation

-------------------------------------------------------------------------------
RF Setup: All four transmitters in RUN-ON by 07:30, all at 80 MHz
-------------------------------------------------------------------------------

Run Plan:

1. Scan He3 puff until MC is observed keeping the plasma out of H-mode
by using moderate RF power (~3.5 MW) Ip = 1.2 MA, BT~7.9 T,
nl_04~0.85

2. Scan He3 where low MC was observed with high power (4.5 MW).

3. Scan density to optimize target for H-mode

4. Scan Ip to optimize target for H-mode

5. Scan antenna phase.
-------------------------------------------------------------------------------



Results:

This was a difficult run, with many TF crowbars at high field. One
problem appeared to be fixed after shot 8, but problems occured in a
different TF cabinet on shot 13.

There were 2 full length shots at 7.8 Tesla (shots 11 and 12) and 2
partial shots with RF at 7.8 Tesla (shots 2 and 4). There were also 2
shots at lower field, where H-mode thresholds were compared between
D+E and J (shots 1 and 7)

Startup was reliable today.

Scorecard:

Plasmas 8
Fizzles 0
P.S. Tests 5

Total cycles 13

Session Leader Comments
Apr 21 2004 08:17:40:463AM1040421001Steve Wukitch001 5.4 T Ip~1 MA, nl_04~0.85
D: 1 MW ramp [1.1,1.5]sec
E: 1 MW ramp [1.1,1.5]sec
J: 2 MW ramp [0.6,1.]sec
result: plasma - phase +140
D: ran 2 faults
E: ran
J: ran 3 faults
next shot: 8 T, 1.2 MA,, He3 puff ~ 15 msec
Apr 21 2004 08:34:19:873AM1040421002Steve Wukitch002 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma - TF crowbar, early disruption
D: ran max faults
E: ran max faults
J: ran
next shot: 50 kA TF test pulse
Apr 21 2004 10:02:38:547AM1040421003Steve Wukitch003 50 kA TF test
Apr 21 2004 10:25:34:133AM1040421004Steve Wukitch004 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma - TF crowbar, early disruption
D: ran max faults
E: ran
J: ran 2 faults
next shot: 50 kA TF test pulse
Apr 21 2004 12:59:40:500PM1040421005Steve Wukitch005 50 kA TF test pulse
Apr 21 2004 02:09:33:757PM1040421006Steve Wukitch006 50 kA TF test pulse

next: repeat of 001 with 5.2 T
Apr 21 2004 02:23:46:390PM1040421007Steve Wukitch007 5.2 T Ip~1 MA, nl_04~0.85
D: 1 MW ramp [1.1,1.5]sec
E: 1 MW ramp [1.1,1.5]sec
J: 2 MW ramp [0.6,1.]sec
result: plasma - phase +140
D: ran max faults
E: ran
J: ran without J3 - no gate
next shot: 8 T, 1.2 MA, no RF
Apr 21 2004 02:34:05:667PM1040421008Steve Wukitch008 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 15 msec
D: -
E: -
J: -
result: plasma - TF crowbar
Next shot: 50 kA TF test pulse
Apr 21 2004 04:25:03:217PM1040421009Steve Wukitch009 TF test
Apr 21 2004 04:25:11:093PM1040421010Steve Wukitch010 TF test
Apr 21 2004 04:37:11:243PM1040421011Steve Wukitch011 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 30 msec
D: 1 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma
D: ran max faults
E: ran 2 faults
J: ran 5 faults - odd gate behavior on FMIT#4
Apr 21 2004 04:56:02:317PM1040421012Steve Wukitch012 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 30 msec
D: 0.8 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma
D: ran max faults
E: ran 6 faults
J: ran 2 faults
Apr 21 2004 07:13:18:467PM1040421013Steve Wukitch013 7.9 T Ip~1.2 MA, nl_04~1, He3 puff ~ 45 msec
D: 0.8 MW ramp [0.6,1.3]sec
E: 1 MW ramp [0.6,1.3]sec
J: 2 MW ramp [0.6,1.3]sec
result: plasma TF crowbar
D: ran 1 fault
E: ran 1 faults
J: ran 2 faults

Physics Operator Comments
Apr 21 2004 08:07:07:250AMEarl MarmarMP#203: 8T He3 Heating

Session leader: Wukitch
Physics operator: Marmar

Overnight ECDC in D2 at 2e-4 Torr

Run begins at 08:00 and ends at 20:00.

Power systems the same as 1040407002 (1.0 MA, 5.4 T, lower X-point)

Once instrumentation has been checked we will load shot
1040407019 for 8T operation.

A-coils should be configured as on 1040409002 (+Dtop -Dbot -Jtop +Jbot)

Gas setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar Hybrid enabled (PG1)
leave B-side upper with 15 psi He3 Hybrid enabled (PG2)
fill C-side with 30 psi D2 Hybrid enabled (PG3)

Disable NINJA

Enable the following gatevalves: ECE, VUV, DNB

Necessary diagnostics:
GPC2 set for 8 T, TCI, PCI, FRECE (5.4 T discharge)
McPherson/Chromex to monitor He3
halo current diagnostics, TF scanner
OH coax resistance and thermocouple instrumentation

-------------------------------------------------------------------------------
RF Setup: All four transmitters in RUN-ON by 07:30, all at 80 MHz
-------------------------------------------------------------------------------

Run Plan:

1. Scan He3 puff until MC is observed keeping the plasma out of H-mode by using moderate RF power (~3.5 MW) Ip = 1.2 MA, BT~7.9 T, nl_04~0.85

2. Scan He3 where low MC was observed with high power (4.5 MW).

3. Scan density to optimize target for H-mode

4. Scan Ip to optimize target for H-mode

5. Scan antenna phase.
-------------------------------------------------------------------------------

Apr 21 2004 08:16:05:100AM1040421001Earl Marmarplasma
5.4 T fiducial; 2 H-modes (~2MW RF, staggered. first J, then D+E)
Apr 21 2004 08:30:35:120AM1040421002Earl Marmarload 1040407019
reduce He3 puff (PG2) to 15 ms from 30
plasma

TF crowbar, followed by all PF breakers pulling, then disrupt at .895s
Apr 21 2004 10:07:21:843AM1040421003Earl Marmar50 kA TF magnet test
Apr 21 2004 01:15:41:527PM1040421004Earl Marmarno PCS changes (from shot 2)

plasma

almost the same as shot 2, TF crowbar, PF breakers pull, disrupt at .96 s)

Engineering estimate: at least 1 hour before next test/shot.
Further delay to replace TF breaker (#3)
Apr 21 2004 12:57:49:767PM1040421005Earl Marmar50 kA TF magnet test
Apr 21 2004 02:05:06:443PM1040421006Earl Marmardelay before the shot to add TF instrumentation

50 kA TF test
Apr 21 2004 02:12:18:317PM1040421007Earl Marmarreload shot 1, reduce |flat-top TF current|
I_tf now -142077 from -150000 on shot 1

plasma

Apr 21 2004 02:33:18:260PM1040421008Earl Marmarreload 1040421006 (like 004 but 30 msec He3 puff)

no RF for this one (eliminate as cause of TF problems?)

plasma, made it all the way through, but TF still crowbarred at .68 s

there will be another delay before the next shot
Apr 21 2004 03:53:34:870PM1040421009Earl Marmar50 kA TF test
Apr 21 2004 03:58:08:510PM1040421010Earl Marmar8 Tesla TF test
Apr 21 2004 04:34:10:027PM1040421011Earl Marmartry for plasma again
still 30 msec He3 puff

plasma, ramps all the way down
TF ok this time
Apr 21 2004 04:58:08:173PM1040421012Earl Marmarno pcs changes

plasma
30 msec He3 puff
Jim Terry reports He level is increasing shot to shot
Apr 21 2004 05:20:14:337PM1040421013Earl Marmarincrease He3 PG2 puff to 45 msec

plasma
very early TF crowbar (~35 msec)
disrupt at .78s

delay before next shot

Engineering Operator Comments
ShotTimeTypeStatusComment
108:04:59:790AMPlasmaOk
208:21:26:437AMPlasmaBadTF type 1 fault(IOC)
309:58:12:597AMTestOkTF 50kA plc Test
410:13:09:060AMPlasmaBadTF type 1 Flt
512:55:15:893PMTestOk50 KA TF Test
601:58:04:760PMTestOktf 50k PLC TEST
702:10:35:630PMPlasmaOk
802:23:27:000PMPlasmaBadTF type 1 flt
903:51:06:823PMTestOkTF 50kA plc test
1004:03:33:570PMTestOkTF 8T test shot
1104:21:30:580PMPlasmaOk
1204:47:21:273PMPlasmaOk
1305:10:09:327PMPlasmaBadTF, IOC Conv 3