Miniproposals

Miniproposal: 050 Date Filed: 4/8/1994 Title: Trace Impurity Transport (Laser Ablation Impurity Injection) First Author: Michael Graf Session Leader: Michael Graf (shots 1-34)

Engineering Operator Run Comment

graf/goetz

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:10:400PM

Author: To Be Determined

Session Leader Summary -- 940527 S.L.: Graf P.O.: Goetz E.O.: Silva/Daigle A run in support of MP 050 -- Trace Impurity Transport.... One goal of today's run was to inject laser blow-off impurities into a variety of plasmas to help obtain a scaling of confinement times. Due to the difficulties experienced earlier in the week, plasma quality expectations were modest. A current scan was determined to be the easiest scan of plasma parameters with a reasonable chance of success. To this end, we began with shot 940526022 which had a stable flat-top of 650 kA and a controlled ramp-down. A decision had been made earlier to not ECDC before the day's run. In light of the problems achieving reliable plasmas earlier in the week, I thought it would be an interesting (albeit courageous) experiment to see if the lack of ECDC made any noticeable difference. Three out of four duds to start the day, however, had me thinking that perhaps I should have chosen to be more daring during someone else's run. Physics Operator Goetz assures me, however, that field problems could easily account for the lack of breakdown during those early shots. The ECDC experiment remains inconclusive, therefore. Once reliable, quasi-limited discharges were obtained (shot 6) with suitable injections of scandium during the flat-top (at t=0.55 sec), the current scan was begun. Shots 6 and 9 were at 650 kA, and good (but not outstanding) injection signals were obtained on the McPherson, HIREX, soft x-ray arrays, etc... Last fall's campaign definitely seemed to have larger signals for seemingly identical injections. Whether this is due to differences in injection geometry (there ideally should be none) or to some real physics inherent in the non-diverted discharges which were run needs to be investigated. At any rate, 'good enough' signals were obtained for most shots today. The current was scanned to 750 kA (shot 10), 850 kA (shots 11,13), 600 kA (shot 14), 550 kA (shot 15), 450 kA (shot 17). Satisfied with the current scan, we began injecting different materials into identical shots (shots 18(Si), 19(Ca), 20,23,25(Mo)) at 800 kA. These injections were also all at t=0.55 sec. This was done in an attempt to evaluate the edge cooling effect of the various materials. Using the grating polychromator, strongest edge cooling was seen for the moly injections (perhaps no great surprise). More work will definitely be necessary on MP 045A -- Cold Pulse Propagation in the future. This is work that is easily done as a piggy-back experiment. Injections were next performed into moderate RF power (<0.8 MW) discharges (shots 26,27(Sc),30,31,32(Fe)). Shots 33 and 34 duplicated 32 and 31 without any RF. The usefulness of those experiments is still being determined. It is hoped that some conclusion can be drawn regarding the spatial distributions of the injected materials (via soft x-ray diode array measurements) with and without RF. In an attempt to placate as many graduate students as possible in a single run day, Closed Loop Response (MP 053) experiments in support of Gerry Tinios were also performed. Shot 20 involved a programmed +1 cm step in ZCUR for a duration of 60 ms (0.65-0.71 sec). The resulting disruption, I am told, did hamper neither the acquisition of useful data, nor the expected graduation date of the relevant party. This run can be classified as relatively successful. While the plasmas were of an unique nature (not really diverted, but riding on the inner nose (of the divertor)), and so are of limited usefulness when comparing with fully diverted or fully limited shots, there were enough good discharges that one cannot really complain. The remainder of MP 050 will be carried out as a series of piggy-back experiments on appropriate days.

Physics Operator Summaries

Entered: Jul 7 2004 04:36:51:600PM

Author: To Be Determined

Physics operator summary for 940527 EO: Silva/Daigle PO: Goetz SL: Graf Run 940527 was in support of Mini-Proposal #050 - Trace Impurity Transport. To this end, shot 940526022 was loaded into the hybrid. This was the last 'good' shot from 940526 and had 650 kA and a successful rampdown. The only change made was to add some pulse gas after 0.25s to try and increase the density. No ECDC was performed before the run. Today's goals were to try and complete MP #050, do a little cold pulse propagation, a little RF conditioning, and a little closed loop response. All goals accomplished today. The run was plagued by DUDS. Tweaks to Bz (IC_EF4) and Br 'seemed' to make the null better, but after a few shots another dud would occur. The nulls were 'acceptable' for 2-3msec for shots that went and <1msec for those that didn't. Fill pressure for the run was between 1.0 and 1.2 e-5 with no correlation between plasmas and duds. All plasmas but two ran to completion. One was killed by too much argon and the other was killed by the return step from the Closed Loop Mini-Proposal. This second disruption was followed by a fizzle. It was determined today that a pressure of ~2.5 PSIA in the plenum is the right amount to achieve a happy medium for HIREX measurements. From an operator standpoint, the gains on the ZCUR controller were fiddled with. Without proportional gain for 100 msec the amplitude of the z-position oscillation was reduced slightly and only 2mm of position drift was seen. With no proportional gain and a derivative gain of 0.5, there is 4mm of position drift. It appears that the OH2L voltage oscillation is independent of its input. This phenomenon will be investigated further on 940531. There was no ECDC prior to this run due to leader perogative. The beginning of the day was dud-dud but fields can explain the problems. The limiter discharges ran today had Zeff ~ 1.5. There was a moly-deuterium burst at the beginning of all shots except for those with Ip~.45MA. Engineering today: Reliable day today for the power systems. One shot lost to the alternator voltage beginning to ramp down before PULSE and one shot lost to an ACK failure. Scorecard: 34 shots = 20 plasmas + 3 fizzles + 9 duds + 2 lost shots Shot summary for Run 940527 Reload of 940526022 Changes: Add PULSE_GAS_3 after 0.25s Shot change result ____ _____ ______ 1 P_0=1.1e-5 dud 2 P_0=1.3e-5 dud 3 IC_EF4=-970A fizzle 4 P_0=1.2e-5 BR_0 offset = -.0035 dud 5 IC_EF4=-985A fizzle 6 IC_EF4U to -990A; P_0=1.2e-5 plasma 7 lower PULSE_GAS_3 dud 8 IC_EF2L and IC_EF2U to -1650A (make the null bigger) dud 9 IC_EF4=-1015A to cure Bz plasma 10 IP=-740000 plasma 11 IP=-840000; PULSE_GAS_1 to 0.65s plasma 12 lower PULSE_GAS_3 after 0.2 no shot 13 no changes plasma 14 IP=-550000; B_SIDE_LOWER plenum pressure =2.5 plasma 15 IP=-520000 plasma 16 IP=-420000; raise PULSE_GAS_3 between .1 and .15 dud 17 P_0=1.2e-5 plasma 18 reload 940527013; low power RF; IP=-800000 plasma 19 P_ZCUR=1.5 plasma 20 no RF; .01m ZCUR step from .65 to .71 plasma 21 no integral gain on ZCUR from .65 to .71 (check ZCUR osc.) fizzle 22 P_0=1.1e-5 dud 23 P_IC_OH2U to 2 at -.03 (stop osc.?) plasma 24 raise PULSE_GAS_3 after .2sec; turn integrator back on at .65 dud 25 BR_0 offset = -.003; IC_EF4=-1025A; P_0=1.2e-5 plasma 26 RF on at .5 plasma 27 no changes plasma 28 notch ZCUR derivative gain at .60 to .70 no shot 29 no changes dud 30 IC_EF4=-1035A plasma 31 drop ZCUR derivative gain to 0 at .60 to .70 plasma 32 ZCUR D gain back to 1.; ZCUR P gain notch at .65 to .70 PULSE_GAS_1 to 0.4sec plasma 33 ZCUR P gain to 0 from .60 to .70; change RCUR ramp .1 to .2 plasma 34 ZCUR D gain to .5 from .60 to .70 plasma

Session Leader Comments
May 27 1994 08:12:34:290AM		Michael Graf	Trace impurity transport run. Looking for well-behaved flat-tops at a range of currents (.4-1 MA); starting with good shot from yesterday (940526022). Hoping for diverted discharges, but will settle for anything achievable. Will start by injecting scandium during flat-top; later will try moly,silicon, etc... GPC set up to look for cold pulse propagation. X-ray diode arrays set up for 25 kHz burst around time of injection. HIREX chords looking at He-like scandium lines.
May 27 1994 08:44:36:830AM	940527001	Michael Graf	set Sc injection trigger at 500 msec. Dud. Nice spot on scandium slide, though.
May 27 1994 08:57:41:280AM	940527002	Michael Graf	set Sc injection trigger at 500 msec. Dud. Nice spot on scandium slide, though.
May 27 1994 09:10:41:210AM	940527003	Michael Graf	set Sc injection trigger at 500 msec. Fizzle (barely).
May 27 1994 09:11:00:240AM	940527003	Michael Graf	set Sc injection trigger at 500 msec. Fizzle (barely).
May 27 1994 09:37:04:210AM	940527004	Michael Graf	set Sc injection trigger at 500 msec. Dud.
May 27 1994 09:42:12:140AM	940527005	Michael Graf	set Sc injection trigger at 500 msec. strong fizzle, almost went.
May 27 1994 09:58:05:940AM	940527006	Michael Graf	set Sc injection trigger at 500 msec. good shot. not a lot of scandium seen, though.
May 27 1994 10:15:06:190AM	940527007	Michael Graf	set Sc injection trigger at 500 msec. dud...
May 27 1994 10:42:33:140AM	940527008	Michael Graf	set Sc injection trigger at 500 msec. dud...
May 27 1994 10:52:05:400AM	940527009	Michael Graf	set Sc injection trigger at 500 msec. good shot. lowered flash lamp energyfor this shot (645 to 641). better signals on softs, McP, same on HIREX
May 27 1994 10:57:34:900AM	940527009	Michael Graf	set Sc injection trigger at 500 msec. good shot. lowered flash lamp energy for this shot (645 to 641). better signals on softs, McP, same on HIREX
May 27 1994 11:12:07:460AM	940527010	Michael Graf	set Sc injection trigger at 500 msec. good shot. lowered flash lamp energy for this shot (641 to 635). better signals on softs, McP, slightly better on HIREX
May 27 1994 11:12:29:950AM	940527010	Michael Graf	set Sc injection trigger at 500 msec. good shot. lowered flash lamp energy for this shot (641 to 635). better signals on softs, McP, slightly better on HIREX
May 27 1994 11:12:36:900AM	940527010	Michael Graf	set Sc injection trigger at 500 msec. good shot. lowered flash lamp energy for this shot (641 to 635). better signals on softs, McP, slightly better on HIREX
May 27 1994 11:25:04:700AM	940527011	Michael Graf	set Sc injection trigger at 550 msec this time. good shot. argon disr'n at 740. lowered flash lamp energy for this shot (635 to 630).
May 27 1994 11:47:33:570AM	940527013	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 12:07:01:090PM	940527014	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 12:07:28:830PM	940527014	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 12:07:33:620PM	940527014	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 12:41:24:970PM	940527015	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 12:42:15:920PM	940527016	Michael Graf	set Sc injection trigger at 550 msec this time. Dud.
May 27 1994 01:12:53:720PM	940527017	Michael Graf	set Sc injection trigger at 550 msec this time. good shot.
May 27 1994 01:13:17:280PM	940527018	Michael Graf	set silicon injection trigger at 550 msec this time. good shot at 800 kA
May 27 1994 01:35:50:810PM	940527019	Michael Graf	set calcium injection trigger at 550 msec this time. good shot at 800 kA
May 27 1994 01:53:08:260PM	940527020	Michael Graf	set molybdenum injection trigger at 550 msec this time. good shot at 800 kA
May 27 1994 01:58:26:330PM	940527021	Michael Graf	set molybdenum injection trigger at 550 msec this time. strong fizzle.
May 27 1994 02:10:14:390PM	940527021	Michael Graf	set molybdenum injection trigger at 550 msec this time. strong fizzle.
May 27 1994 02:10:41:950PM	940527022	Michael Graf	set molybdenum injection trigger at 550 msec this time. dud.
May 27 1994 02:23:50:270PM	940527023	Michael Graf	set molybdenum injection trigger at 550 msec this time. good shot at 800 kA. mnay naturals around injection time
May 27 1994 02:24:55:640PM	940527023	Michael Graf	set molybdenum injection trigger at 550 msec this time. good shot at 800 kA. mnay naturals around injection time
May 27 1994 02:43:09:860PM	940527024	Michael Graf	set molybdenum injection trigger at 550 msec this time. dud.
May 27 1994 03:01:39:720PM	940527025	Michael Graf	set molybdenum injection trigger at 550 msec this time. good shot. great injection..
May 27 1994 03:11:03:370PM	940527026	Michael Graf	set scandium injection trigger at 550 msec this time. good shot.
May 27 1994 03:25:44:590PM	940527027	Michael Graf	set scandium injection trigger at 550 msec this time. good shot. tough to see on softs over RF induced emission.
May 27 1994 04:44:31:570PM	940527030	Michael Graf	set iron injection trigger at 550 msec this time. good shot. poor injection.
May 27 1994 04:45:04:790PM	940527031	Michael Graf	set iron injection trigger at 550 msec this time. good shot.
May 27 1994 04:45:12:080PM	940527032	Michael Graf	set iron injection trigger at 550 msec this time. good shot.
May 27 1994 04:55:32:750PM	940527033	Michael Graf	set iron injection trigger at 550 msec this time. good shot. No RF during injection this time.
May 27 1994 05:03:38:080PM	940527034	Michael Graf	set iron injection trigger at 550 msec this time. good shot. No RF during injection this time.

Physics Operator Comments
May 27 1994 08:32:41:500AM		John Goetz	RUN 940527 Mini Proposal 050 - Trace Impurity Transport Start from 940526022 - add some Pulse_Gas_3 after 0.25 sec - no pre-run ECDC
May 27 1994 08:53:14:750AM	940527001	John Goetz	Shot 001: Dud null looks as good as shot 22 from yesterday For Shot 002: raise fill pressure to 1.3e-5
May 27 1994 09:20:40:540AM	940527002	John Goetz	Shot 002: Dud Bz a little negative; doesn't cross zero until .01 For Shot 003: IC_EF4 = -970A
May 27 1994 09:21:57:670AM	940527003	John Goetz	Shot 003: Fizzle breakdown at .01 sec - late Br appears to be a bit positive compared to yesterday For Shot 004: BR_0 offset = -.0035 P_0 = 1.2e-5
May 27 1994 09:34:03:330AM	940527004	John Goetz	Shot 004: Dud null at .005-.006 looks good then too much Bz For Shot 004: IC_EF4 = -985A
May 27 1994 09:47:01:260AM	940527005	John Goetz	Shot 005: Fizzle breakdown at .006sec Halpha lasts until .035sec scatterplot says too much gas For Shot 006: lower P_0 to 1.0e-5
May 27 1994 10:02:06:030AM	940527006	John Goetz	Shot 006: Plasma rampdown Ip=.65; nel=7e19 For Shot 007: lower PULSE_GAS_3 after 0.2 sec (to raise temperature)
May 27 1994 10:23:42:430AM	940527007	John Goetz	Shot 007: Plasma dud very small null For Shot 008: change IC_EF2L and IC_EF2U to -1650A from -1700A to try to make the null better
May 27 1994 10:59:42:000AM	940527008	John Goetz	Shot 008: Dud Bz too positive because of the EF2 change radial field better For Shot 009: IC_EF4 to -1015A for vertical field change
May 27 1994 11:00:43:870AM	940527009	John Goetz	Shot 009: Plasma Ip=.65; nel=7e19; Te(0)=1.5 For Shot 010: IP=-740000
May 27 1994 11:18:57:050AM	940527010	John Goetz	Shot 010: Plasma Ip=.75; nel=8e19; Te(0)=1.6 very triangular For Shot 010: IP=-840000 PULSE_GAS_1 moved to 0.65sec
May 27 1994 11:31:59:310AM	940527011	John Goetz	Shot 011: Plasma Ip=.85; nel=7.4e19; Te(0)=1.6 argon induced disruption at 0.74 For Shot 012: PULSE_GAS_3 lowered after 0.2 to reduce density
May 27 1994 11:39:49:610AM	940527012	John Goetz	Shot 012: dud ACK failure - no shot For Shot 013: no changes
May 27 1994 11:58:13:030AM	940527013	John Goetz	Shot 013: plasma Ip=0.85; nel=7.7e19; Te(0)=1.9 disruptive late during rampdown - argon related For Shot 014: IP=-550000 B_SIDE_LOWER plenum pressure = 2.4PSIA
May 27 1994 12:09:26:460PM	940527014	John Goetz	Shot 014: plasma Ip=0.58; nel=5e19; Te(0)=1.8 less argon - good rampdown For Shot 015: IP=-520000
May 27 1994 12:29:25:530PM	940527015	John Goetz	Shot 015: plasma Ip=0.55; nel=5e19; Te(0)=1.8 a bit of moly from .1 to .15 For Shot 016: IP=-420000 a little more PULSE_GAS_3 early
May 27 1994 12:50:20:020PM	940527016	John Goetz	Shot 016: dud Horne's opinion: Ripple in OH1 causes lump of Bz at the wrong time. For Shot 017: P_0=1.2e-5
May 27 1994 01:02:01:630PM	940527017	John Goetz	Shot 017: plasma Ip=.46; nel=5e19; Te(0)=1.5 For Shot 018: reload 940527013 IP=-800000 low power RF
May 27 1994 01:19:38:710PM	940527018	John Goetz	Shot 018: plasma Ip=.81; nel=7.5e19; Te(0)=1.8 [ 2.1 after RF ] For Shot 019: P_ZCUR(2)=1.5
May 27 1994 01:36:38:390PM	940527019	John Goetz	Shot 019: plasma Ip=.81; nel=7.1e19; Te(0)=1.8 [ 2.15 after RF ] For Shot 020: program .01m step in ZCUR from .65 to .71sec turned off RF
May 27 1994 01:54:54:600PM	940527020	John Goetz	Shot 020: plasma Ip=.81; nel=7.2e19; Te(0)=2.0 disruption at .74 - programmed Z step happens, but on down jump, the plasma oversteps and gets thrown out of the machine For Shot 021: low power RF turn off integral gain on ZCUR (check for cause of ZCUR oscill.)
May 27 1994 02:01:47:780PM	940527021	John Goetz	Shot 021: fizzle breakdown at .005sec Halpha to .03sec null just about the same as always For Shot 022: P_0=1.1e-5
May 27 1994 02:19:02:400PM	940527022	John Goetz	Shot 022: dud null significantly worse - bad in OH2L corner oscillations in OH2's and OH1 For Shot 023: lower P gain on IC_OH2U to 2 at -.03 to try and reduce oscill.
May 27 1994 02:37:37:740PM	940527023	John Goetz	Shot 023: plasma Ip=.80; nel=6.4e19; Te(0)=1.9 (2.25 RF) natural injection at .62 For Shot 024: raise PULSE_GAS_3 after .2 sec
May 27 1994 02:47:15:600PM	940527024	John Goetz	Shot 024: dud Br too negative? Bz too positive? For Shot 025: BR_0 offset to -.003 IC_EF4 to -1025A P_0=1.2e-5
May 27 1994 03:02:27:740PM	940527025	John Goetz	Shot 025: plasma Ip=.81; nel=7e19; Te(0)=1.7 (2.0 RF) For Shot 026: RF on at .5sec
May 27 1994 03:14:58:620PM	940527026	John Goetz	Shot 026: plasma Ip=.81; nel=8.2e19; Te(0)=1.7 (2.0 RF) For Shot 027: no changes
May 27 1994 03:29:25:360PM	940527027	John Goetz	Shot 027: plasma Ip=.81; nel=8.0e19; Te(0)=1.5 (1.9 RF) For Shot 028: notch ZCUR derivative gain from .65 to .70
May 27 1994 03:47:29:460PM	940527028	John Goetz	Shot 028: no shot alternator voltage ramped down just before PULSE For Shot 029: no changes
May 27 1994 03:59:20:020PM	940527029	John Goetz	Shot 029: dud Bz too positive For Shot 030: IC_EF4 to -1035A
May 27 1994 04:14:11:990PM	940527030	John Goetz	Shot 030: plasma Ip=.81; nel=8.0e19; Te(0)= no apparant change in ZCUR due to the gain switch For Shot 031: drop ZCUR derivative gain to 0 from .65 to .70
May 27 1994 04:29:17:600PM	940527031	John Goetz	Shot 031: plasma Ip=.81; nel=8.1e19; Te(0)=1.3 no change in ZCUR due to the gain switch For Shot 032: drop ZCUR proportional gain to 0.5 from .65 to .70 return ZCUR derivative gain to 1 from .65 to .70 PULSE_GAS_1 to 0.4sec
May 27 1994 04:42:41:470PM	940527032	John Goetz	Shot 032: plasma Ip=.81; nel=7.9e19; Te(0)=1.5 no change in ZCUR oscillation due to the gain switch For Shot 033: drop ZCUR proportional gain to 0 from .65 to .70 change RCUR ramp from .1 to .2
May 27 1994 04:56:11:440PM	940527033	John Goetz	Shot 033: plasma Ip=.81; nel=7.4e19; Te(0)=1.5 ZCUR oscillation decreases a little, z position droops 2mm For Shot 034: drop ZCUR derivative gain to 0 from .60 to .70 for all previous shots that mention ZCUR gain switches, the times should be .60 and .70
May 27 1994 05:16:14:460PM	940527034	John Goetz	Shot 034: plasma Ip=.81; nel=7.5e19; Te(0)=1.8 ZCUR oscillation decreases a little more, z position droops 4mm

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:39:42:300AM	Plasma	Ok	dud 08:40
2	08:52:53:780AM	Plasma	Ok
3	09:06:12:660AM	Plasma	Bad	Fizzle No faults
4	09:21:21:010AM	Plasma	Ok
5	09:34:42:400AM	Plasma	Ok	dud No faults
6	09:46:36:070AM	Plasma	Ok	great shot
7	10:05:58:680AM	Plasma	Ok
8	10:24:43:170AM	Plasma	Ok
9	10:38:51:720AM	Plasma	Ok	Good 650KA Ip
10	10:59:21:960AM	Plasma	Ok	2 in a row
11	11:19:34:310AM	Plasma	Ok	plasma disrupt
12	11:32:52:720AM	Plasma	Bad	IGOR ACK failure on transition to pulse
13	11:40:42:720AM	Plasma	Ok	plasma
14	11:57:50:070AM	Plasma	Ok	Good 580KA Ip
15	12:16:40:080PM	Plasma	Ok	plasma
16	12:37:31:760PM	Plasma	Ok
17	12:49:57:770PM	Plasma	Ok	plasma shot No faults.
18	01:06:06:590PM	Plasma	Ok	Good shot No faults
19	01:23:08:940PM	Plasma	Ok	PLASMA SHOT NO FAULTS
20	01:36:21:820PM	Plasma	Ok	PLASMA SHOT O.K.
21	01:53:54:660PM	Plasma	Bad	DUD NO FAULTS.
22	02:04:12:900PM	Plasma	Bad	DUD NO FAULTS.
23	02:17:40:180PM	Plasma	Ok	NO FAULTS
24	02:33:53:950PM	Plasma	Ok	DUD NO FAULTS
25	02:47:51:000PM	Plasma	Ok	NO FAULTS
26	03:04:06:190PM	Plasma	Ok	GOOD, NO FAULTS
27	03:16:12:880PM	Plasma	Ok	GOOD SHOT NO FAULTS.
28	03:29:54:070PM	Plasma	Bad	ALT VOLTAGE FAULT
29	03:48:31:180PM	Plasma	Ok	GOOD, NO FAULTS
30	04:00:02:380PM	Plasma	Ok	GOOD SHOT
31	04:15:24:260PM	Plasma	Ok	GOOD SHOT NO FAULTS.
32	04:29:48:580PM	Plasma	Ok	GOOD SHOT NO FAULTS
33	04:44:03:670PM	Plasma	Ok	GOOD, NO FAULTS
34	05:01:02:430PM	Plasma	Ok	NO FAULTS