| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Earl Marmar |
| Physics operator(s): | Steve Wolfe |
| Engineering operator(s): | Bill Cochran,Gary Dekow,Bill Parkin |
| Engineering Operator Run Comment |
| MP#414 Divertor Conditioning with Li pellets in near-DN discharges |
| Session Leader Plans |
| Entered: Mar 17 2005 08:35:49:577AM |
| Author: Earl Marmar |
| MP 414 Li pellet wall conditioning in double null Previous experience with the use of lithium for wall conditioning in tokamaks has been mixed. On TFTR, dramatic reductions in recycling were observed, first through Li pellet conditioning[1], and later with other techniques utilizing Li evaporation[2]. Target plasmas with reduced hydrogenic content following intensive Li conditioning were used as targets for beam fueling in the supershot regime, and led directly to the highest fusion performance discharges obtained on TFTR, including both D-D and D-T plasmas. Experiments on C-Mod[3] and DIII-D[4] showed little or no effect on wall conditioning and recycling after Li pellet injections. Since C-Mod has no carbon PFCs, while TFTR used them exclusively, one conjecture for the differences between these two sets of experiments relates to wall chemistry. However, DIII-D also has carbon plasma-facing tiles, and so this does not yield a compelling explanation. Recent C-Mod results on scrape-off-layer flows, and their dependence on separatrix topology[5], may provide a unifying explanation for these seemingly contradictory results. TFTR had no divertor, and the discharges were limited on the inner wall. For both DIII-D and C-Mod, previous Li wall conditioning attempts were carried out in single-null divertor topology. Based on our current understanding of particle dynamics and SOL flows, we would expect that most of the lithium leaving the plasma following pellet injection will do so near the outboard midplane, and then will be deposited preferentially at the inner divertor strike point, on the high field side, carried by the strong asymmetric flows; additional Li might be deposited on the outboard limiters, due to the intermittent ( blob ) transport. However, little, or none of the Li would be expected to flow to the outer divertor leg, which is the region that sees the dominant heat flux in single null cases. This picture is also consistent with the results of post campaign tile analysis carried out by Dennis Whyte, showing that boron is eroded from the outer strike area, and deposited at the inner strike region. While we do not entirely know the overall dynamics, one explanation for the need to re-boronize after a few hundred discharges, is this erosion of the boron layer from the highest heat flux region of the outer divertor. 13C tracer experiments on DIII-D show similar results on erosion and deposition[6]. For the TFTR limited case, the Li should have been deposited on the inner wall, just in the regions that also experience the highest heat flux. Based on our current understanding of the origin of the strong SOL flows, an approach which should allow for the escaping lithium to find the high heat flux outer divertor leg, is to inject pellets into double-null plasmas. In this case the flows cannot reach the inner leg, and particles leaving on the low-field side must end up on the outer legs (both upper and lower) and possibly the outboard limiters. This opens a new line of investigation, which might be fruitful for controlling molybdenum influx, and perhaps recycling as well, without the need for boronization. SHOT SEQUENCE Start from a standard .8 MA SNL shot, nl_04=1e20 m^-2. Apply RF from .6 to 1.0 seconds, 3 MW (1 MW each from D, E and J) to obtain HMode(s) (ELM free or EDA). Tune to double null by about 1.1 seconds, monitoring SOL flows to find the SSEP that corresponds to the stagnated double-null. Use multiple probe plunges as possible and appropriate. ISP will probably be the most sensitive measure; we want minimum flow and density to the inner midplane. (4 shots) Keep SSEP fixed at that value until 1.55 seconds. Add Li pellet injection, 3 pellets per discharge, injected at 1.1, 1.25 and 1.4 seconds. This gives enough time for most of the lithium to leave the discharge before the subsequent pellet is injected or the equilibrium changes. Monitor discharge conditions (impurities, etc.), particularly during the RF phase of each subsequent discharge, continuing to inject Li pellets during the double-null phase of the discharges. (15 shots) Continue to run the same plasma, but without Li injection, again monitoring all relevant parameters (5 shots). |
| Physics Operators Plans |
| Entered: Mar 16 2005 03:54:34:700PM |
| Author: Steve Wolfe |
| Engineering setup and Physop Plan for
Thursday, 17-Mar-2005 MP#414 Divertor Conditioning with Li pellets in near-DN discharges SL: Marmar PO: wolfe Overnight ECDC in D2, bake at 60C Power systems as on 1050311024 Gas setup: ___________ fill B-top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 2 psi Ar Hybrid ENabled (PG1) leave B-side upper with 15 psi He3 Hybrid DISabled (PG2) fill B-main (former C-side) with 30 psi D2, Hybrid enabled (PG3) fill lower capillaries (NINJA plenum) with 10 psi D2 Vacuum setup: _____________ GV1 OPEN, Pump valves NOT closed in pulse Enable ECE, Z-bolo shutters (assuming no vacuum problems) Enable Li pellet injector gate valve ICRF setup: all transmitters in run on by 8:30 am ------------------------------------------------------ PO Plan: --------- Load active segment from seg4 of 1050311024, which has SSEP control and goes from SSEP=-.005 to 0 starting at .9sec. It also had copious runaways and some small injections after 1sec; we don't want either of those, so pick a good startup from 1050315 or 1050316, and hope for the best on the injections. Move SSEP transition to be between 1.0 and 1.1sec, and possibly decrease pre-transition value to -.01; also work on the offset, since -2500 seems not to be correct anymore. Leave SSEP at 0 until 1.55sec, then go back to lower null for most of rampdown (? Not sure why, that's what's implied in the MP. Check with ESM on this.) Remove drop in ZXL gain at 0.9sec Raise nl_04 to 1.0e20 from 9e19. Tune SSEP and equilibrium shape based on flow stagnation measurement with probes. (4shots) Leave equilibrium alone as SL carries out pellet injection experiments during DN phase, as described in the MP. Try to keep startup happy, otherwise resist the urge to tweak. Leave a good one on the drum. Go home and drink lots of Irish Whisky in honor of St Pat's Day, while watching first round of NCAA tournament. |
| Session Leader Summaries |
| Entered: Mar 19 2005 09:43:43:513AM |
| Author: Earl Marmar |
| We accomplished a substantial fraction of the run plan.
The configuration was tuned after a few shots, using the ISP to look at density and flows to determine the SSEP that gave the smallest of each. This was around SSEP = -1 to -2 mm. Lithium pellets were injected on many subsequent shots. However, in most cases, the plasma disrupted after either the first or second pellet. We never managed to get 3 pellets into a single discharge. A total of 21 pellets were injected, all but 2 into near double-null. Shot 24 was LSN all the way through, with 2 pellets, and no disruption. There were no obvious effects of the lithium on any of monitored plasma parameters, including radiated power, h-factor, H/(H+D) and core moly radiation (HIREX). Chromex measurements clearly saw neutral Li emission from the lower outer divertor. Mo I emission from this region was weak even before the first pellet, and did not appear to change much. While the numerous post-pellet disruptions may have muddled the result somewhat, the initial conclusion is that the pellets had little or no effect in terms of wall conditioning. There are a number of pulses with steady RF at 3MW total (D+E+J), giving dithery/tiny ELM H-modes; h_89~1 assuming 100% absorbed. Total power (RF launched, plus ohmic) was over 3.5 MW on most shots. Shots 22, 23, 26, 27 and 28 are good examples. H/(H+D) started the day at or below 5%; by the last shot it was approaching 10%. |
| Physics Operator Summaries |
| Entered: Mar 17 2005 06:15:30:147PM |
| Author: Steve Wolfe |
| Physop Summary for March 17, 2005
MP#414 SL: Marmar PO: wolfe EO: Cochran, Dekow, Parkin The equilibrium change setup went ok, but the DN plasmas were not very robust and we had lots of pellet-induced disruptions. We ended up with a flow stagnation point according to Brian's ISP when EFIT claimed SSEP= -1 to -2mm, which corresponded to a programmed value of -.003. I decided not to mess with the SSEP offset, because the discrepancy seems to be between the fluxihh value and the EFIT value, not really an offset as such. There were some apparent injections while close to DN, especially on the SSEP~0 shots, as there had been on 1050311. We did not try a full upper null, but there is still a concern something is not right in the upper vessel. No dust was visible on the cameras, but they now have filters. Li injection did not have any apparent beneficial effects. It may have been implicated in problems in the current ramp phase (see below), but probably not. While we had fewer successful pellets than hoped, and more disruptions, the experimental plan was essentially completed, without positive result. We had several runaway shots early in the run, all associated with outside bouncing startups. At shot 10 I changed the RCUR offset in seg1 from 1500 to 2000, while also increasing pg4 for the third or fourth time, to 35msec. We did not have any further runaway shots, at least at the level of getting snow on the cameras. However, after that we ran into a new pathology: very radiative, cold (hollow temperature profiles) current rise phase in segment 4, basically between 200 and 400msec. Ian reported peaked core radiation, and Amanda was seeing hollow Te with Te0 as low as 300eV. This effect was especially pronounced after a big injection around 400ms killed shot 12, but Ian says the radiation was already starting to increase by shot 9. Current was not reaching flattop until after .6sec, and hanging around at 650kA a long time, which was not the case early in the run. Shot#1 had Te0~2500eV at 200ms, and shot 28 had 600eV. I suspected that something about the SSEP control, which was on from the beginning of seg4, was causing the slow startup, maybe forcing an interaction with the outer limiter, or the upper chamber. I made a number of unsuccessful attempts to remedy the situation, including gas and equilibrium tweaks. At shot 21 I copied essentially all the waveforms from a standard lower null shot, except for SSEP, into the active segment 4; that failed to improve the ramp phase at all. On shot 24 we reverted to a standard lower null (from 1050316018), and that didn't help either. It didn't get worse over the last five shots, may have been improving very slightly. The last five shots (24-28) were lower null, the last 4 without pellets, as called for in the plan. The current ramp may have improved marginally over this period, but certainly did not get back to the state at the beginning of the day. There were two no power shots. On shot 2 a TF breaker pulled out in init; this turned out to be an actual breaker failure, and we had a long delay to swap in the spare breaker. On shot 17 dpcs_init hung up in Init, although it finally completed, after we had opened the breakers and set up for no power. DPCS apparently worked fine on this shot; this is the first time I know of that the DPCS_INIT task has had any problem. We also had one very short plasma (<40msec) on shot 15; this was effectively a fizzle, although the current got to 130kA before it either hit something or was hit by something at 32msec. Scorecard: Tests/No power 2 Duds 0 Fizzles 0 Early term 2 (including one ~40msec and one ~400msec) Plasmas 24 ---------- --- Shots 28 |
| Session Leader Comments | |||
| Mar 17 2005 10:06:13:930AM | 1050317001 | Earl Marmar | LPI at 1.1 second; got the pellet; J3 off for this shot, so J is a monopole (0.5 MW, J4 only) H/(H+D) ~ .05, rising during RF to ~0.08, then maybe drops slightly after the pellet |
| Mar 17 2005 09:30:56:823AM | 1050317002 | Earl Marmar | no power shot; power supply problem during init |
| Mar 17 2005 10:33:12:417AM | 1050317003 | Earl Marmar | plasma single pellet again at 1.1 seconds disrupt at 1.25 seconds, after lithium mostly gone. Brian reports it took a little more gas to fuel this shot, compared to shot 3 several short dithery H-modes; RF power unavailable (digitizer problem) |
| Mar 17 2005 11:29:56:090AM | 1050317004 | Earl Marmar | no pellet this shot |
| Mar 17 2005 11:30:38:057AM | 1050317005 | Earl Marmar | no pellet, ISP scanning looks like small counter flow reduce late SSEP slightly for next shot |
| Mar 17 2005 11:31:09:963AM | 1050317006 | Earl Marmar | looks like less flow on ISP we'll stay here for now |
| Mar 17 2005 11:42:25:167AM | 1050317007 | Earl Marmar | program for 3 Li pellets (1.2, 1.35, 1.5 seconds) only got the first pellet disrupts at 1.245 s; density increase from pellet has mostly decayed by then |
| Mar 17 2005 12:00:07:777PM | 1050317008 | Earl Marmar | Li pellets programmed for 1.2 and 1.4 seconds - position 1, barrels 3 and 4 got both pellets; pretty prompt disruption after the second pellet more RF trips on this shot; hard to compare Mo with previous shots |
| Mar 17 2005 12:09:09:323PM | 1050317008 | Earl Marmar | Li pellets programmed for 1.2, 1.35 and 1.5 seconds Got the first only, then pretty prompt disrupt (35 msec after the pellet hits) density decayed most of the way before the disruption This shot had a much lower target density, because of a TCI feedback problem |
| Mar 17 2005 12:44:23:777PM | 1050317010 | Earl Marmar | 2 Li pellets (1.2 and 1.45 seconds). Got both. Disrupt after second pellet. |
| Mar 17 2005 12:59:58:620PM | 1050317011 | Earl Marmar | Li pellets at 1.33 and 1.5 Got the first pellet, then disrupt |
| Mar 17 2005 12:59:05:010PM | 1050317012 | Earl Marmar | programmed for Li pellets at 1.15 and 1.3 seconds early disruption, before RF; no pellets |
| Mar 17 2005 01:19:51:027PM | 1050317013 | Earl Marmar | try again pellets programmed for 1.15 and 1.3 seconds didn't get the first pellet Got the second, no disruption |
| Mar 17 2005 01:33:24:370PM | 1050317014 | Earl Marmar | pellets programmed for 1.15, 1.3 and 1.45 seconds got the first, disrupt before the second |
| Mar 17 2005 01:49:04:260PM | 1050317015 | Earl Marmar | Li pellets programmed at 1.15 and 1.3 very early demise (~100 kA) no pellets fired |
| Mar 17 2005 02:06:53:213PM | 1050317016 | Earl Marmar | Li pellets programmed for 1.15 and 1.3 Got only the first, no disruption |
| Mar 17 2005 02:15:35:090PM | 1050317017 | Earl Marmar | no power shot data system problem during init |
| Mar 17 2005 02:33:12:260PM | 1050317018 | Earl Marmar | programmed for 3 pellets 1.15, 1.3, 1.45 s got the first, then disrupts after about 45 msec |
| Mar 17 2005 03:07:22:993PM | 1050317019 | Earl Marmar | 2 pellets called for and injected disrupt after second pellet, most of density decayed no J-port on this shot |
| Mar 17 2005 03:34:10:993PM | 1050317021 | Earl Marmar | programmed for 2 pellets got the first at 1.15, then disrupt later |
| Mar 17 2005 03:47:57:667PM | 1050317022 | Earl Marmar | program for 1 pellet at 1.15 did not get the pellet |
| Mar 17 2005 04:02:55:010PM | 1050317023 | Earl Marmar | set for 3 pellets, got 2, then disrupt |
| Mar 17 2005 04:48:14:870PM | 1050317024 | Earl Marmar | standard lower single null shot all the way through programmed for 3 pellets (1.0, 1.25, 1.45 s); got the first 2, although second density rise is smaller no third pellet no disruption |
| Mar 17 2005 04:49:44:883PM | 1050317025 | Earl Marmar | no pellets standard LSN watch to see if Li disappears shot by shot from the divertor (chromex) continue to monitor moly, radiated power, etc. for the rest of the shots today |
| Mar 17 2005 04:50:14:277PM | 1050317026 | Earl Marmar | repeat |
| Mar 17 2005 04:58:30:680PM | 1050317027 | Earl Marmar | repeat |
| Mar 17 2005 05:09:48:823PM | 1050317028 | Earl Marmar | repeat nothing dramatically different |
| Physics Operator Comments | |||
| Mar 17 2005 08:01:58:770AM | Steve Wolfe | Setting up for Earl's Li Pellet experiment MP#414:
Startup seg using last settings from yesterday- IC_ef4= -1335 RCUR offset=1500 Br0 = -.002 pg4 = 28ms v_oh1 = 100 between 0 and 11ms v_ef3 = 2650,2400,2500 @[-.001,.005,.012] Current and Bz rise could stand being faster than on 1050316018, but there was no hesitation and no hards. Import seg4 from 1050311024 seg2 off, seg4 on change title LN->DN (instead of UN) Increase nl04 9e19 to 1e20 Note: zcur is set to 0 instead of -.009 Remove drop in ZXL gain Move SSEP swing to be from 1.0 to 1.1sec (was 0.9 to 0.94) and back down to LN between 1.55 and 1.8 reduce pg3 at .1, increase a little at .3:.6 Load into model Load at 17-Mar-2005 08:01:32.00 Open tree /home/wolfe/pcs_scratch -1 Open tree done | |
| Mar 17 2005 09:15:03:480AM | 1050317001 | Steve Wolfe | Shot#1: Try for plasma, similar to 1050311024 but
with slower and later ssep swing (see plan) LPI will fire at 1.1sec on this shot to check out system Plasma, full length. Got a pellet, also injections from upper chamber. SSEP looks a little bit positive after the swing, Looks like ssep goes more positive in rampdown, though I programmed it to go negative again? Gain is off at 1.5sec. Next shot: extend ssep gain to 2sec |
| Mar 17 2005 09:34:08:870AM | 1050317002 | Steve Wolfe | Shot#2:extend ssep gain to 2sec
pellets will fire again. Blab not in yet, so no ISP data Forgot to load the ssep change, but the breakers came out in INIT so we had a no power shot anyway. DPCS timed out but I didn't get a message. |
| Mar 17 2005 09:52:02:260AM | 1050317002 | Steve Wolfe | There is a delay while the engineers look at a problem
with one of the TF breakers in the power room. The cell is available for CONTROLLED ACCESS |
| Mar 17 2005 10:29:25:837AM | 1050317003 | Steve Wolfe | Shot#3:extend ssep gain to 2sec (loaded this time)
pellets will fire again. Brian wants the inner gap changed for targeting the ISP increase clearin by 3mm to .003 and rcur by 1.5mm from 0.7sec on. plasma to 1.25sec EFC floors at 1.15sec? |
| Mar 17 2005 10:54:12:150AM | 1050317004 | Steve Wolfe | Shot#4: No pellet this time, reduce Ip gain from 9 to 5
after 1sec May need to slow the ssep transition down. plasma to 1.77sec, one small injection on Dalpha at 1.29sec. SSEp still doesn't come down in rampdown Gain is there, try adding another point later in the waveform; DPCS may not be holding that last point? |
| Mar 17 2005 11:09:32:230AM | 1050317005 | Steve Wolfe | Shot#5: try adding another point later in the SSEP
waveform; DPCS may not be holding that last point? Brian will scan, still no pellet. Plasma to 1.65, with runaways. Lots of action on halpha from 1.45sec on. next shot: 1mm less far on SSEP. |
| Mar 17 2005 11:21:54:727AM | 1050317006 | Steve Wolfe | Shot#6: SSEP to -.003, Pg4 to 31msec
plasma to 1.75, no injections on Halpha in second half of shot. Still no pellet, RF off at 0.9sec SSEP is -1 to -2mm after 1sec, still doesn't seem to be going back down according to EFIT? next shot: Drop NL04 to 7e19 after RF |
| Mar 17 2005 11:41:55:040AM | 1050317007 | Steve Wolfe | Shot#7: Drop NL04 to 7e19 after RF, pellets to start
at 1.2sec Runaways again, and short. Disrupts at 1.26sec Startup is bouncy again. Density rises after 1 sec, may be NINJA, may be eq. change. next shot: NINJA off. Increase pg4 again |
| Mar 17 2005 11:52:28:213AM | 1050317008 | Steve Wolfe | Shot#8: NINJA off. Increase pg4 to 32ms!
plasma to 1.4sec, second pellet killed it. Density is down before the pellet this time, so the rise may have been NINJA. Voltage goes up to 2V at the first pellet and never comes back down. A couple of additional spikes on Halpha between the pellets may be dust. |
| Mar 17 2005 12:08:11:777PM | 1050317009 | Steve Wolfe | Shot#9: No changes
Can't get rid of the runaways! plasma to 1.24sec, gas turned off at 0.3sec and density ended up at 6e19 during the RF; it may be repetitive H-modes? Wmhd reaches 99kJ. First pellet killed it though. Next shot: Increase RCUR offset in seg1 |
| Mar 17 2005 12:37:33:993PM | 1050317010 | Steve Wolfe | Shot#10: Increase RCUR offset in seg1 1500 to 2000,pg4 to 35msec
plasma to 1.51sec Second pellet killed it, after nearly recovering. Current and Bz rise still seem slow, no runaways. |
| Mar 17 2005 12:51:56:243PM | 1050317011 | Steve Wolfe | Shot#11: No pcs changes
plasma to 1.38sec; that was the second pellet, but didn't get the first pellet. |
| Mar 17 2005 01:07:32:400PM | 1050317012 | Steve Wolfe | Shot#12: No pcs changes
Early disruption, .45sec In trouble from .33, around crossover, then something big comes in around 0.4sec No obvious control problems or failed sensors. Blame it on meteorites and try again |
| Mar 17 2005 01:19:50:430PM | 1050317013 | Steve Wolfe | Shot#13: No pcs changes
plasma to 1.8sec. One pellet. SSEP is still not going back down in rampdown according to EFIT; Aout thinks it is doing almost what it's supposed to, which means the predictor is wrong or else EFIT is. Aout is +1700 at 1.8sec, when the current is down below 400kA, which means 4mm error which may be right; I'm now only asking for about a 4mm change. Next shot: Ask for SSEP=-.015 in rampdown |
| Mar 17 2005 01:35:05:290PM | 1050317014 | Steve Wolfe | Shot#14: Ask for SSEP=-.015 in rampdown
plasma to 1.21, looks like first pellet at 1.15 did it in. We had a couple of early injections .13 and .21sec seen on Halpha which take smal bites out of the current rise. Current gain steps are at .34(small) and .63 Next shot: move the second step to .5sec |
| Mar 17 2005 01:48:28:883PM | 1050317015 | Steve Wolfe | Shot#15: Ask for SSEP=-.015 in rampdown
move the second Ip gain step to .5sec Got to 130kA at 32msec and died? next shot: reduce inner gap and try to move outer lower strike point down |
| Mar 17 2005 02:27:13:400PM | 1050317016 | Steve Wolfe | Shot#16: RXL flat at 0, ZXL downto 0 at .6, -.005 at 1.5
clearin back to 0, rcur in by .0015 plasma to 1.7sec, 1 pellet at 1.15sec early seg2 current rise is ratty; looks like EF4 turns around at about .25, when ef2_by_ef4 comes on. Next shot: try to move ZXL even lower, drop Zcur |
| Mar 17 2005 02:16:29:323PM | 1050317017 | Steve Wolfe | Shot#17: ZXL down another 5mm, ZCur to -.009
dpcs_init hung in init/ NO POWER shot |
| Mar 17 2005 02:35:58:730PM | 1050317018 | Steve Wolfe | Shot#18: ZXL down another 5mm, ZCur to -.009
Try again. Plasma to 1.21sec, killed by pellet next shot: Earl wants the strike point after 1.1 where it is during RF, so I need to move zxl down more; the right way would be to turn on strkpsi. |
| Mar 17 2005 02:49:16:277PM | 1050317019 | Steve Wolfe | Shot#19: Earl wants the strike point after 1.1
where it is during RF, so I need to move zxl down more. Plasma to 1.44, second pellet did it in. Strike point stil too high at pellet. And we have a baseline offset on f15! It doesn't look bad, may be ok. Yijun says FMIT#3 has a problem. |
| Mar 17 2005 03:13:33:290PM | 1050317020 | Steve Wolfe | Shot#20: Try moving rxl in during the shot
Increase early pg3 in seg2 to try to reduce reported core radiation between .2 and .4sec plasma to 1.23sec, early phase looks worse |
| Mar 17 2005 03:32:54:383PM | 1050317021 | Steve Wolfe | Shot#21: Remove pg3 increase, set Ic_ef4 to 2000
ef2_by_ef4 to -2000 (from -3000) plasma to 1.2sec, current rise is worse. EF2U actually goes to zero at .3 this time. Had an f27 baseline warning this time; may have fixed itself Next shot: copy in waveforms from seg2 for RCUR, CLEARIN, ZCUR, RXL, ZXL, EF2by EF4, IC_EF4,Ip |
| Mar 17 2005 03:43:26:680PM | 1050317022 | Steve Wolfe | Shot#22:copy in waveforms from seg2 for
RCUR, CLEARIN, ZCUR, RXL, ZXL, EF2by EF4, IC_EF4,Ip decrease nl04 to 8e18 plasma to 1.9sec, current ramp still terrible. No pellets. Flux loops look ok this time. next shot: Move rcur in before .6sec to increase right gap. |
| Mar 17 2005 03:57:09:557PM | 1050317023 | Steve Wolfe | Shot#23: Move rcur in by 2mm before .5sec to increase
right gap. Decrease early SSEP from -7mm to -1cm, start sweep at .95sec plasma to 1.33sec, still horrible early. F27 has baseline shift this time. Also F01. next shot: Change to seg2 (LN like yesterday) |
| Mar 17 2005 04:12:58:573PM | 1050317024 | Steve Wolfe | Shot#24: Change to seg2 (LN like yesterday)
plasma to 1.83, First 500msec still horrible. Solid lower null throughout. Got two pellets. next shot: No pcs changes, no pellets, extend RF |
| Mar 17 2005 04:27:25:883PM | 1050317025 | Steve Wolfe | Shot#25: plasma to 1.8, looks like type 3 elmy H-mode
Current rise still bad, early radiation and low central Te. Not getting some updates on my scopes, we lost the announce in init and had to restart it. |
| Mar 17 2005 04:50:18:570PM | 1050317026 | Steve Wolfe | Shot#26: No pcs changes, no pellets
plasma full length, current rise still bad. Breakdown is very late, after 7ms Fields look ok or at least no different. Leave it alone and see if it gets better. |
| Mar 17 2005 05:04:12:073PM | 1050317027 | Steve Wolfe | Shot#27: No pcs changes, no pellets
Plasma full length, still poor current rise. One H->L around .95sec, RF stays on. Breakdown back earlier, 6.3ms. next shot: No changes, will be last shot of the day |
| Mar 17 2005 05:13:16:307PM | 1050317028 | Steve Wolfe | Shot#28: No changes
plasma, full length Current rise phase not noticeably better, Te0 may be a little higher early. Still have a major fast spike on Halpha at .219sec. Two short H->L in the middle of a clean RF pulse. END OF RUN |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:05:28:057AM | Plasma | Ok | |
| 2 | 09:26:05:777AM | Plasma | Bad | TF Breaker Failure |
| 3 | 10:21:42:307AM | Plasma | Ok | |
| 4 | 10:42:51:573AM | Plasma | Ok | |
| 5 | 10:55:52:167AM | Plasma | Ok | |
| 6 | 11:12:31:370AM | Plasma | Ok | |
| 7 | 11:31:49:823AM | Plasma | Ok | |
| 8 | 11:45:21:947AM | Plasma | Ok | |
| 9 | 11:59:49:823AM | Plasma | Ok | |
| 10 | 12:26:59:680PM | Plasma | Ok | |
| 11 | 12:43:15:900PM | Plasma | Ok | |
| 12 | 12:56:06:667PM | Plasma | Ok | |
| 13 | 01:10:04:870PM | Plasma | Ok | |
| 14 | 01:26:02:040PM | Plasma | Ok | |
| 15 | 01:43:43:040PM | Plasma | Ok | |
| 16 | 01:56:53:133PM | Plasma | Ok | |
| 17 | 02:13:33:150PM | Plasma | Bad | Hybrid System Hung |
| 18 | 02:25:45:430PM | Plasma | Ok | |
| 19 | 02:38:37:917PM | Plasma | Ok | |
| 20 | 03:05:50:917PM | Plasma | Ok | |
| 21 | 03:19:16:540PM | Plasma | Ok | |
| 22 | 03:38:18:590PM | Plasma | Ok | |
| 23 | 03:50:25:323PM | Plasma | Ok | |
| 24 | 04:04:13:040PM | Plasma | Ok | |
| 25 | 04:21:32:290PM | Plasma | Ok | |
| 26 | 04:38:42:590PM | Plasma | Ok | |
| 27 | 04:54:01:040PM | Plasma | Ok | |
| 28 | 05:06:28:900PM | Plasma | Ok | |