Alcator C-Mod Run 1021018 Information

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Miniproposals
Miniproposal:
Date Filed:
Title:
First Author:
Session Leader: Lee (shots 1-25)
Miniproposal:317
Date Filed: 8/21/2002
Title:ITB Study with Expanded Diagnostic Set
First Author:Catherine Fiore
Session Leader:Catherine Fiore (shots 1-25)

Operators
Session leader(s): Lee,Catherine Fiore
Physics operator(s):Bill Rowan
Engineering operator(s):Ed Fitzgerald

Engineering Operator Run Comment
MP#317 ITB Studies with improved diagnostics SL:Fiore/Lee PO:Rowan EO:Fi

Session Leader Plans

Physics Operators Plans

Session Leader Summaries
Entered: Jul 7 2004 03:49:31:367PM
Author: To Be Determined

This run is in support of MP#317, ITB with improved diagnostics. The purpose
of this experiment is to reproduce the off-axis ITB studies from 2001
described in MP269, MP289a,and MP291a with the expanded diagnostic set which is
now available. The goal is to obtain detailed density profiles from visible
bremsstrahlung and Thomson scattering, detailed temperature measurements from
Thomson scattering, ECE, HIREX, and CX (if available) diagnostics, and improved
plasma rotation data for input into TRANSP and GS2 or other gyrokinetic codes.
This proposal calls for obtaining EDA H-mode plasmas at a series of magnetic
fields, suitable for obtaining both high and low field ITBs.

We will begin with a shot from October 11th (14) where we obtained an ITB
using 70 MHz off axis on the low field side. The target field is 6.3 T for 80
Mhz off-axis heating, however.

We manage to get a few poor quality ITBs. Mostly we had a problem maintaining
the H-modes for a sufficient time for ITBs to build up. Obtaining low
field side ITBs with 80 Mhz remains an elusive proposition at this point.

Shot summary:

1021018001 5.8T
Good shot, late H-mode. 5.8 T. No power from E-port

1021018002 6.2 T
Good shot. We are trying to get H-modes with just D-port power because of
a control system problem on E-port. The H-mode came in about 1.1 s.
The field was 6.2T and rf power was 1.2, both a little lower than requested.
No ITB except for an ENmode.

1021018003 6.3 T
Good shot. The H-mode came in about 1.s. RF power was almost 1.4 MW. No ITB.

1021018004 6.3 T
Good shot. The H-mode came in about 1.s. RF power was almost 1.4 MW. No
ITB. Scaling from the run of 10/11/02 says that we should actually have the
field slightly higher, so we will go to 6.4 T

1021018005 6.4 T
Good shot. The H-mode came in about 1.1s. RF power was almost 1.4 MW.
Possible ITB.

1021018006 6.4 T
Good shot. The H-mode came in about 1.s. RF power was almost 1.4 MW.
Apparent ITB.

1021018007 6.4 T
Good shot. The H-mode came in about 0.9s. We raised the current to 0.9MA.
RF power was almost 1.4 MW. Apparent ITB. Density at H-mode was a little
high, and we will lower it slightly for the next shot.

1021018008 6.4 T
Good shot. The H-mode came in about 0.65s, dropped out and restruck at 1.s.
RF power was almost 1.4 MW. Possible ITB, although it looks a little ratty on
first inspection. Density at H-mode onset was on target. We are going to try
to raise the rf power a little higher.

1021018009 6.4 T
Good shot. 6.4T. Three H-modes. RF power was almost 1.5 MW but had a lot of
drop outs. No ITB.

1021018010 6.4 T
Good shot. Three H-modes. RF power was almost 1.5 MW but had a lot of drop
outs. No ITB. RF group wants to lower the power for the next shot.

1021018011 6.4 T
Good shot. Late H-mode RF power was 1.MW and steady. RF group will raise
the power for the next shot. No Dalsa data was stored for that shot. It was
unlikely to have an ITB.

1021018012 6.4 T
Good shot. Two H-modes, starting after 1.1s. RF power was 1.2 MW and
steady. No ITB. RF group will raise the power for the next shot. Dalsa has
been restored.

1021018013 6.4 T
Good shot. Two H-modes. RF power was 1. 4 MW but drops out frequently.
Slight density peaking on the 2nd H-mode, but RF drop outs are a problem.

1021018014 6.4 T
Good shot. Four H-modes. RF power was 1. 4 MW with many drop outs. Slight
density peaking on the last H-mode, but RF drop outs are a problem. We will
let the RF group check further to see if E-port can be resuscitated.

1021018015 6.4 T
Good shot.Three H-modes. Eport has been fixed, but did not fire into the
plasma because someone accidently left it going into the dummy load. RF power
was 1. MW with 1 drop out. No ITB.

1021018016 6.4 T
Good shot. 6.4T. Three H-modes. 2 MW RF. No ITB. We would like to get back
to having a steady H-mode, so we will try increasing the target density
slightly.

1021018017
Fizzle

1021018018 6.4 T
Good shot. Two H-modes. Density peaks up on the first one, probable ITB.
2 MW RF

1021018019 6.4 T
Good shot. Two H-modes. No apparent ITB

1021018020 6.47 T
Good shot. Three H-modes. No apparent ITB

1021018021 6.47 T
Good shot. Three H-modes. No apparent ITB

1021018022 6.41 T
Good shot. Two H-modes. No apparent ITB

1021018023
No Power

1021018024 6.41 T
Good shot. 3 H-modes. No ITB

1021018025 6.41 T
Good shot. 3 H-modes. Some peaking on second H-mode, although it looks more
like it was trying to go into an EN mode. Plasma current was 1 MA.

Physics Operator Summaries
Entered: Jul 7 2004 04:37:16:600PM
Author: To Be Determined
Physop Summary for Friday 10/18/2002. 1021018.

Run Plan------------------------------------------------------------------
MP#317 ITB Studies with improved diagnostics

The idea is to get more data on low-field side resonance ITB's.

Start from 1021011018 but with the field increased to 6.3 T
and try to get an ITB shot with 80MHz ICRF (D&E) (low-field side resonance).
This may require a TF scan in increments of 0.1T to 0.05 T to find the ITB.
If we are able to get a reasonable ITB under these conditions, we'll
scan the field, and perhaps the current, to document the ITB behavior.
If time and plasma behavior permits.

If we are unsuccessful, we will scan the field for Davis Lee to obtain
rotation data.

Engineering Setup----------------------------------------------------------
SL: Fiore and Lee
PO: Rowan

Engineering Setup

Power Systems as on 1021011018
Increase the TF current limit to 165 kA.

Overnight ECDC in D2 at 2e-4 torr off by 7:00AM

Run to begin at 9:00 AM

Gas setup:

B-Top 6 psi D2 Hybrid Enabled (PG4)
B-side lower 1 psi Ar Hybrid Enabled (PG1)
B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC)
C-Side 30 psi D2 Hybrid Enabled (PG3)
J-Bottom as is, Hybrid DISABLED

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

RF Setup: #1,2 in Run On by 7:00AM

Results------------------------------------------------------------------
The search for ITBs was largely unsuccessful. Initially only D antenna
was avaiable as the transmitter for E had a control problem. Some time
was spent in a repair attempt with no success. Using the one antenna, a
few shots were produced with ITBs. In an attempt to improve coupling to
the antenna, the outer gap was decreased by approximately 2 mm. This
resulted in faulting. Returning the outer gap to the original value did
not improve things. Additional time was devoted to the repair of the
control system for the transmitter for E. This time the repair was
successful and 2 MW was produced for essentially the remainder of the
run. Small TF, IP, and ne scans did not produce good ITBs. See SL
report for details of shot numbers for the ITB discharges.


Score Card
Plasmas 23
Disruptions 0
Fizzles 1
Duds 0
Engineering 1
Total 25


Log----------------------------------------------------------------------

ECDC off at approximately 7am

LOAD/CLEAN 1021011014

Coldstart by engineering operator

Increased ITF to 164000.

Imported segment 1 from shot 1021017029 and increased
pg4 from 30 to 32 ms



001. Plasma BT= 5.8. Not what I wanted.
1 MW. One H-mode late.

Pause for power room access for RF

Next shot. itf = -174000.


002. Plasma.
D port antenna is begin tested alone.
BT = 6.2T with ITF = -174000
RF 1.2 MW

Next shot. ITF = -178000

003. Plasma
BT = 6.3 T as requested
RF 1.4 MW
H-mode at approx 1 s

Next shot. Repeat

004. Plasma
RF 1.3 MW
H-mode just after 1 s

Next shot. SL requests 6.4 T. ITF set to -180000

005. Plasma
BT = 6.4 T
H-mode. a bit later than last shot
RF 1.3 MW

Next shot. Repeat.

006. Plasma
H-mode at 1s
RF 1.4 MW
ITB see SL

Next shot.
IP increased from 800 kA to 900 kA to decrease q95


007. Plasma
IP = 0.9 MA
H-mode earlier; .9s
q95 is 5.4 at 1.2s
RF 1.3 MW
ITB

Next shot.
Reduced the density demand from 8.0 to 7.5
SL concerned about the density being a little high
on entry into H-mode. Match 006.

008. Plasma
RF 1.4 MW
nl_04 - 8.6e+19 at entry into h-mode

Next shot.
Decrease the outer gap from 10 mm to 8 mm
by increasing rcur by 1 mm

009. Plasma
4 H-modes
Outer gap is approx 8 mm
RF 1.4 MW with many drop outs

Next shot.
Increase the outer gap from 8 mm to 10 mm
by decreasing rcur by 1 mm

010. Plasma
Several H-modes
Outer gap is approx 10 mm
RF 1.4 MW with drop outs

Next shot.
Reduce RF power to remove drop outs.


011. Plasma
Couple of H-modes.
RF 0.9 MW

Next shot.
Increase RF power

012. Plasma
2 h-modes
RF 1.1 MW

Next shot.
Increase RF Power


013. Plasma
H-modes
RF 1.3 MW with drop outs.

Next shot : repeat


014. Plasma
Several H-modes
RF 1.4 MW with drop outs

Next shot.
Pause first to try to bring E up
No other changes

015. Plasma
H-modes
RF 1.1 MW; one drop out

Next shot.
Try for D&E


016. Plasma
3 h-modes

Next shot.
Increase the density: nl_04 changed from 7.5 to 5.0e+19
5 minutes of ecdc before this shot


017. Fizzle

Next shot. Reduced pg4 by 2 ms to 30 ms


018. Plasma
RF 2 MW
ITB

Next shot.
Repeat


019. Plasma
RF 2 MW
H-modes

Next shot.
Changed ITF = -181300. Expect Bt = 6.45

020. Plasma
3 H-modes
RF 2 MW with drop outs

Next shot
Repeat


021. Plasma
3 h-modes
RF 1.8 MW

Next shot.
ITF = -179339. Expect BT=6.4


022. Plasma
BT = 6.42T
RF 2 MW

Next shot.
Raise zxu by 2 cm to 5 cm

023. no power shot
I^2t fault

024. Plasma
3 H-modes


Next shot.
ZXU returned to 3 cm
IP increased to 1 MA


025. Plasma
Multiple h-modes
RF 2 MW.
IP = 1 MA







Session Leader Comments
Oct 18 2002 09:04:41:133AMCatherine FioreThis run is in support of MP#317, ITB with improved diagnostics. The purpose
of this experiment is to reproduce the off-axis ITB studies from 2001
described in MP269, MP289a,and MP291a with the expanded diagnostic set which is
now available. The goal is to obtain detailed density profiles from visible
bremsstrahlung and Thomson scattering, detailed temperature measurements from
Thomson scattering, ECE, HIREX, and CX (if available) diagnostics, and improved
plasma rotation data for input into TRANSP and GS2 or other gyrokinetic codes.
This proposal calls for obtaining EDA H-mode plasmas at a series of magnetic
fields, suitable for obtaining both high and low field ITBs.

We will begin with a shot from October 11th (14) where we obtained an ITB using
70 MHz off axis on the low field side. The target field is 6.3 T for 80 Mhz off-axis
heating, however.
Oct 18 2002 09:07:19:107AM1021018001Catherine Fiore Good shot, late H-mode. 5.8 T. No power from E-port
Oct 18 2002 10:07:15:450AM1021018002Catherine Fiore Good shot. We are trying to get H-modes with just D-port power because of
a control system problem on E-port. The H-mode came in about 1.1 s.
The field was 6.2T and rf power was 1.2, both a little lower than requested.
No ITB except for an ENmode.
Oct 18 2002 10:20:21:360AM1021018003Catherine Fiore Good shot. 6.3T The H-mode came in about 1.s.
RF power was almost 1.4 MW. No ITB
Oct 18 2002 10:35:30:053AM1021018004Catherine Fiore Good shot. 6.3T The H-mode came in about 1.s.
RF power was almost 1.4 MW. No ITB.
Scaling from the run of 10/11/02 says that we should actually have the
field slightly higher, so we will go to 6.4 T
Oct 18 2002 10:58:05:980AM1021018005Catherine Fiore Good shot. 6.4T The H-mode came in about 1.1s.
RF power was almost 1.4 MW. Possible ITB.

Oct 18 2002 11:17:28:040AM1021018006Catherine Fiore Good shot. 6.4T The H-mode came in about 1.s.
RF power was almost 1.4 MW. Apparent ITB.

Oct 18 2002 11:36:34:193AM1021018007Catherine Fiore Good shot. 6.4T The H-mode came in about 0.9s. We raised the current
to 0.9MA. RF power was almost 1.4 MW. Apparent ITB. Density at H-mode
was a little high, and we will lower it slightly for the next shot.

Oct 18 2002 11:53:30:190AM1021018008Catherine Fiore Good shot. 6.4T The H-mode came in about 0.65s, dropped out and restruck at
1.s. RF power was almost 1.4 MW. Possible ITB, although it looks a little ratty on
first inspection. Density at H-mode onset was
on target. We are going to try to raise the rf power a little higher.


Oct 18 2002 12:06:58:397PM1021018009Catherine Fiore Good shot. 6.4T. hree H-modes. RF power was almost 1.5 MW but had a lot of
drop outs. No ITB.

Oct 18 2002 12:28:46:197PM1021018010Catherine Fiore Good shot. 6.4T. hree H-modes. RF power was almost 1.5 MW but had a lot of
drop outs. No ITB. RF group wants to lower the power for the next shot.

Oct 18 2002 12:52:55:013PM1021018011Catherine Fiore Good shot. 6.4T. Late H-mode RF power was 1. MW and steady.
No ITB. RF group will raise the power for the next shot. No Dalsa data was
stored for that shot. It was unlikely to have an ITB.

Oct 18 2002 01:07:08:690PM1021018012Catherine Fiore Good shot. 6.4T. Two H-modes, starting after 1.1s RF power was 1. 2 MW and steady.
No ITB. RF group will raise the power for the next shot. Dalsa has been restored.

Oct 18 2002 01:47:38:317PM1021018013Catherine Fiore Good shot. 6.4T. Two H-modes. RF power was 1. 4 MW but drops out frequently.
Slight density peaking on the 2nd H-mode, but RF drop outs are a problem.

Oct 18 2002 01:46:36:237PM1021018014Catherine Fiore Good shot. 6.4T. Four H-modes. RF power was 1. 4 MW with many drop outs.
Slight density peaking on the last H-mode, but RF drop outs are a problem. We will let
the RF group check further to see if E-port can be resuscitated.

Oct 18 2002 02:21:00:620PM1021018015Catherine Fiore Good shot. 6.4T. Three H-modes. Eport has been fixed, but did not fire into the plasma
because someone accidently left it going into the dummy load. RF power was 1. MW with 1 drop out.
No ITB.
Oct 18 2002 02:44:50:623PM1021018016Catherine Fiore Good shot. 6.4T. Three H-modes. 2 MW RF.
No ITB. We would like to get back to having a steady H-mode, so we will
try increasing the target density slightly.
Oct 18 2002 02:51:15:773PM1021018017Catherine Fiore Fizzle
Oct 18 2002 03:18:09:283PM1021018018Catherine Fiore Good shot. Two H-modes. Density peaks up on the first one, probable ITB.
2 MW RF
Oct 18 2002 03:36:26:267PM1021018019Catherine Fiore Good shot. 6.4 T Two H-modes. No apparent ITB
Oct 18 2002 03:52:56:697PM1021018020Catherine Fiore Good shot. 6.47T Three H-modes. No apparent ITB
Oct 18 2002 04:09:48:880PM1021018021Catherine Fiore Good shot. 6.47T Three H-modes. No apparent ITB
Oct 18 2002 04:31:20:630PM1021018022Catherine Fiore Good shot. 6.41T Two H-modes. No apparent ITB
Oct 18 2002 04:39:43:940PM1021018023Catherine FioreNo Power
Oct 18 2002 04:57:00:170PM1021018024Catherine FioreGood shot. 3 H-modes. No ITB
Oct 18 2002 05:12:55:693PM1021018025Catherine FioreGood shot. 3 H-modes. Some peaking on second H-mode, although it looks more like it
was trying to go into an EN mode.

Physics Operator Comments
Oct 18 2002 08:16:47:170AMBill RowanRun Plan and Engineering Setup for Friday 10/18/2002

MP#317 ITB Studies with improved diagnostics

SL: Fiore and Lee
PO: Rowan

Engineering Setup

Power Systems as on 1021011018
Increase the TF current limit to 165 kA.

Overnight ECDC in D2 at 2e-4 torr off by 7:00AM

Run to begin at 9:00 AM

Gas setup:

B-Top 6 psi D2 Hybrid Enabled (PG4)
B-side lower 1 psi Ar Hybrid Enabled (PG1)
B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC)
C-Side 30 psi D2 Hybrid Enabled (PG3)
J-Bottom as is, Hybrid DISABLED

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

RF Setup: #1,2 in Run On by 7:00AM

Run Plan:
---------

The idea is to get more data on low-field side resonance ITB's.

Start from 1021011018 but with the field increased to 6.3 T
and try to get an ITB shot with 80MHz ICRF (D&E) (low-field side resonance).
This may require a TF scan in increments of 0.1T to 0.05 T to find the ITB.
If we are able to get a reasonable ITB under these conditions, we'll
scan the field, and perhaps the current, to document the ITB behavior.
If time and plasma behavior permits.

If we are unsuccessful, we will scan the field for Davis Lee to obtain
rotation data.
Oct 18 2002 08:45:41:650AMBill RowanECDC off at approximately 7am

LOAD/CLEAN 1021011014

Coldstart by engineering operator

Increased ITF to 164000.

Imported segment 1 from shot 1021017029 and increased
pg4 from 30 to 32 ms
Oct 18 2002 09:18:30:340AM1021018001Bill Rowan001. Plasma BT= 5.8. Not what I wanted.

Pause for power room access for RF

Next shot. itf = -174000.
Oct 18 2002 10:06:13:960AM1021018002Bill Rowan002. Plasma.
D port antenna is used alone.
BT = 6.2T with ITF = -174000
RF 1.2 MW

Next shot. ITF = -178000
Oct 18 2002 10:18:12:247AM1021018003Bill Rowan003. Plasma
BT = 6.3 T as requested
RF 1.4 MW
H-mode at approx 1 s

Next shot. Repeat
Oct 18 2002 10:35:32:757AM1021018004Bill Rowan004. Plasma
RF 1.3 MW
H-mode just after 1 s

Next shot. SL requests 6.4 T. ITF set to -180000
Oct 18 2002 10:55:07:583AM1021018005Bill Rowan005. Plasma
BT = 6.4 T
H-mode. a bit later than last shot
RF 1.3 MW

Next shot. Repeat.
Oct 18 2002 11:17:49:773AM1021018006Bill Rowan006. Plasma
H-mode at 1s
RF 1.4 MW
ITB see SL

Next shot.
IP increased from 800 kA to 900 kA to decrease q95
Oct 18 2002 11:35:54:943AM1021018007Bill Rowan007. Plasma
IP = 0.9 MA
H-mode earlier; .9s
q95 is 5.4 at 1.2s
RF 1.3 MW
ITB

Next shot.
Reduced the density demand from 8.0 to 7.5
SL concerned about the density being a little high
on entry into H-mode. Match 006.
Oct 18 2002 11:53:07:330AM1021018008Bill Rowan008. Plasma
RF 1.4 MW
nl_04 - 8.6e+19 at entry into h-mode

Next shot.
Decrease the outer gap from 10 mm to 8 mm
by increasing rcur by 1 mm
Oct 18 2002 12:10:03:340PM1021018009Bill Rowan009. Plasma
4 H-modes
Outer gap is approx 8 mm
RF 1.4 MW with many drop outs

Next shot.
Increase the outer gap from 8 mm to 10 mm
by decreasing rcur by 1 mm
Oct 18 2002 12:26:13:410PM1021018010Bill Rowan010. Plasma
Several H-modes
Outer gap is approx 10 mm
RF 1.4 MW with drop outs

Next shot.
Reduce RF power to remove drop outs.
Oct 18 2002 12:46:35:787PM1021018011Bill Rowan011. Plasma
Couple of H-modes.
RF 0.9 MW

Next shot.
Increase RF power
Oct 18 2002 01:05:52:707PM1021018012Bill Rowan012. Plasma
2 h-modes
RF 1.1 MW

Next shot.
Increase RF Power
Oct 18 2002 01:25:46:563PM1021018013Bill Rowan013. Plasma
H-modes
RF 1.3 MW with drop outs.

Next shot : repeat
Oct 18 2002 02:14:52:873PM1021018015Bill Rowan014. Plasma
Several H-modes
RF 1.4 MW with drop outs

Next shot.
Pause first to try to bring E up
No other changes
Oct 18 2002 02:21:05:510PM1021018015Bill Rowan015. Plasma
H-modes
RF 1.1 MW; one drop out

Next shot.
Try for D&E
Oct 18 2002 02:43:35:230PM1021018016Bill Rowan016. Plasma
3 h-modes

Next shot.
Increase the density: nl_04 changed from 7.5 to 5.0e+19
5 minutes of ecdc before this shot
Oct 18 2002 02:58:09:940PM1021018017Bill Rowan017. Fizzle

Next shot. Reduced pg4 by 2 ms to 30 ms
Oct 18 2002 03:17:07:237PM1021018018Bill Rowan018. Plasma
RF 2 MW
ITB

Next shot.
Repeat
Oct 18 2002 03:48:17:940PM1021018020Bill Rowan020. Plasma
3 H-modes
RF 2 MW with drop outs

Next shot
Repeat
Oct 18 2002 04:07:59:987PM1021018021Bill Rowan021. Plasma
3 h-modes
RF 1.8 MW

Next shot.
ITF = -179339. Expect BT=6.4
Oct 18 2002 04:31:44:617PM1021018022Bill Rowan022. Plasma
BT = 6.42T
RF 2 MW

Next shot.
Raise zxu by 2 cm to 5 cm
Oct 18 2002 04:37:50:280PM1021018023Bill Rowan023. no power shot
I^2t fault
Oct 18 2002 04:55:37:153PM1021018024Bill Rowan024. Plasma
3 H-modes


Next shot.
ZXU returned to 3 cm
IP increased to 1 MA
Oct 18 2002 05:06:25:640PM1021018025Bill Rowan025. Plasma
Multiple H-modes
Rf 2 MW
IP = 1 MA

Engineering Operator Comments
ShotTimeTypeStatusComment
109:01:43:597AMPlasmaOk
209:56:29:117AMPlasmaOk
310:10:40:500AMPlasmaOk
410:25:33:507AMPlasmaOk
510:45:11:740AMPlasmaOk
611:04:50:863AMPlasmaOk
711:23:44:160AMPlasmaOk
811:41:04:043AMPlasmaOk
912:00:08:213PMPlasmaOk
1012:18:13:493PMPlasmaOk
1112:36:44:160PMPlasmaOk
1212:55:30:377PMPlasmaOk
1301:14:13:687PMPlasmaOk
1401:33:27:123PMPlasmaOk
1502:14:21:453PMPlasmaOk
1602:30:21:133PMPlasmaOk
1702:49:07:427PMPlasmaOk
1803:05:59:953PMPlasmaOk
1903:23:27:310PMPlasmaOk
2003:41:10:727PMPlasmaOk
2103:58:49:503PMPlasmaOk
2204:17:13:813PMPlasmaOk
2304:35:30:433PMPlasmaBadNo power shot, I squared T fault during INIT.
2404:46:07:780PMPlasmaOk
2504:59:18:377PMPlasmaOk