| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Bruce Lipschultz |
| Physics operator(s): | Ian Hutchinson |
| Engineering operator(s): | Joe Daigle,Vinny Bertolino |
| Engineering Operator Run Comment |
| Hutch normal field |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:13:833PM |
| Author: To Be Determined |
| Run 950601 Engineering operator: V. Bertolino Phyics operator: I. Hutchinson Session leader: BLip mp #105: Dependence of Detachment Threshold and Radial Extent on Plasma Current & q. During this run we formed 1 MA flat-plate plasmas. The run was hampered by the lack of interferometer, but nevertheless, we did not observe pressure detachment at the outer divertor even at the highest densities. We will have to analyse the Bremsstrahlung and Thomson data to determine the correspondence to the usual scaling paramter, nl04, with which we usually run discharges. The second aspect of this run that was interesting was that even though there did not appear to be pressure detachment at the highest densities the temperature on probe 8 was low, 3 eV. To maintain the high pressures the density there was very high - 2-3 e21 m^-3. This argues against a hard limit of 5-6 eV below which the plasma is detached. Overall this was run was successfull in developing the flat-plate geometry at 1 MA. We have not determined the detachment threshold for this current. The shot summary follows: shot 1: 800 kA. No interferometer so the density feedback is on the raw bremsstrahlung signal. The estimated density is nl04=1.e20. The scaling used based on yesterday's data was brem (volts) = (nl04 in 10^20/1.74)^2. The sweep went alright around outer div. probe 8. shot 2: disruption shortly after inversion. Otherwise the sweep is slightly better. Again the density roughly equivalent to nl04=1., in this case we got the Thomson - central density of 1.6e20. shot 3: 800 kA, no disruption. Ne0 (YAG) varies from 1.5 - 2 during shot. Sweep has been slowed down but still covers full range around probe 8. Probe 9 still working (knock on wood!). shot 4: same shot but with FSP scan. We are experiencing strong Mo injections every shot. shot 5: 1 MA, no FSP scan or YAG. Unusual shot in that brems. drops around .7 seconds along with sawteeth stopping. We will repeat with FSP. shot 6: disruption of unknown origin. shot 7: disruption at .51 seconds preceded by enormous injection. shot 8: 800 kA and everything fine. No FSP, domed probes 7 and 9 working! shot 9: 1 MA shot, disruption at 1.1 seconds. FSP scan ok. Ne0 = 1-1.5 e20 over the shot. shot 10: disruption at .52 seconds due to VDE. shot 11: shot went fine - Ne0=2.e20. No FSP scan. repeat with FSP. shot 12: Ne0=2 - 2.3e20. FSP scan ok. shot 13: STRIKEOUT, 280 kA halo current. There seems to be an enormous number of problems. At 500 ms the density drops out as the MARFE ends. The gas valve opens wide to compensate however the plasma density does not rise further aggravating problems that have occurred simultaneously with the power supplies. We will back off the programming in a number of areas and try again. shot 14: disruption shot 15: dud shot 16: fine at 800 kA. some small changes to make. shot 17: 800 kA, next shot 1MA. shot 18: 1 MA, Ne0=1.6 rising to 2.2e20. No FSP scan. shot 19: dud, power supply turned off. shot 20: Ne0 varies from 2 to 2.7e20, 1 MA, FSP scan. shot 21: Ne0=2.3-2.8e20. FSP scan ok. shot 22: Ne0 varying from 2.2 - 3.2e20, FSP scan. Looks like beginnings of detachment during latter part of shot. shot 23: Ne0=2.8-3.8e20. FSP scan ok. Still no clear detachment. shot 24: disruption at .64 seconds. MARFE early on. shot 25: shot went fine but no FSP scan. The divertor probe data shows low temperatures on probe 8 (below 5 eV) but very high densities (3e21 m^-3)) such that the pressure is still peaked at the separatrix and no obvious detachment. No Thomson but guess Ne0 > 3e20 by end of shot. shot 26: disruption due to very large injection shortly after .4 seconds. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:54:630PM |
| Author: To Be Determined |
| Physop 950601 Horizontal Plate Divertor SL Blip PO Hutch EO Bertolino/Daigle Summary _______ A rather difficult run, trying for high density, 1MA horizontal plate plasmas. No interferometer so relying on nl_zmeter for density feedback control. The plasmas started well all day after overnight ECDC, but there were a lot of Moly injections, slowly seeming to clean up over the day. The plasma current rise was maintained at a higher than previous ramp rate by delaying the crowbars to 1.7s. This worked fine and had no problems. Up till shot 13, EF2s were allowed to kiss their current limits. The OUT on 13 shows that this was a bad idea because when EF2 exceeds its current limit for any time it develops the integral error problem that means it then comes out of current limit only substantially later. That was the cause of 13's OUT. Again we see that PS problems, horizontal plate and OUTs go together. From 13 till 17 were used to develop a plasma with some clearance of EF2 from its limits. Thereafter plasmas seemed much more satisfactory. We obtained central (YAG) density of 3e20. Trying to go beyond this got much harder. Shot 24 had a big marfe because of too much early gas. Power supplies then reached astonishing voltages before the disruption caused by EF2 rail. It recovered fine on 25 but on the last shot, 26, a brick fell from the top, visible on TV. Scorecard _________ Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax 1 1.457 0.820 2 1.024 0.853 3 1.551 0.817 4 1.548 0.815 5 1.480 1.019 6 0.423 0.822 7 0.514 1.081 8 1.553 0.822 9 1.126 1.016 10 0.529 1.050 11 1.460 1.001 12 1.462 1.006 13 0.771 1.009 14 0.537 0.802 15 0.000 0.021 16 1.481 0.822 17 1.468 0.817 18 1.497 1.014 19 0.000 0.019 20 1.452 1.003 21 1.434 1.003 22 1.431 1.001 23 1.390 1.001 24 0.660 1.078 25 1.421 1.001 26 0.446 0.905 Finished summary for 950601 Total of 26 shots. 26 shots. 24 plasmas. 2 duds. Details _______ Previous nights events: Recovery from the broken TCI window. Load segment 2 from 950509023. Import wire 14 950519005, the old Zmeter feedback for density. Gain zero till 0.25s then at 5. Add 100A to OH1 (to 16.6kA). Put nl_zmeter to 0.33. This should be 950531 12 Fiz Lot of Carbon radiation. 30kA. Bz to 7.0mT from 7.5mT. 13 Fiz 28kA current. Breakdown at 0.55 ms. Fill to 1.8 (from 2.3) 14 Fiz Over 30kA. Just too radiative. Do overnight ECDC. Adjusted early Ip programming to put points at (400kA,.1), (600kA,.16). Removed the voltage steps at crowbar from OH1 and OH2. (Left EF1, no big step). All this is segment 2. Moved crowbar times 50ms later to EF1:.15s, OH1,2:.17s. Hence we are attempting a more rapid current rise. Fill pressure 1.8e-5. nl-zmeter is .33 Got the yag ne trace. It reads 1.8 when nl04 read 1.0e20. 1 CAMAC failure. Eventually found to be a wrong value for the fizzle detector probably typed in because of a focus error. 1 Pla The current rise goes fine. EF2 rails at .31-.4s Delayed the clearin increase at about .3s. 2 Pla Disrupts at 1.04s a vertical jerk apparently caused by the gain switch of the strkpsi at 1s. Got some unpeasant Mo injections. Added more gas (40V at .12s) in the rise. Stepped teh strkpsi gain down at 1s. Moved the sweep earlier. Dropped clearin some more at .35s. Speeded up the clearin rampdown. 3 Pla Ramped down OK but still had a bit of a jerk. EF2s just kissing. Tweaked the strkpsi turn-off some more. Added more early gas: 30V in segment 1. Increased ZXu to try to improve ssep. 4 Pla Cooled the early rise but still getting Mo injections later. Go to 1 MA. Ease off the gas at .03s. Tweak zxu some more. 5 Pla Ran ok but with injections. Tweak Ip gain up during .2-.3s. Raise NL_zmeter gain to 7 from 5. 6 Pla Disrupts at .41s. Caused by a very resistive rise at .15 to .2s. Really dirty early. Runaways apparently. Set early Ip gain to 2. from .1s, removing the step. 7 Pla Disrupts at 0.5s. Appears to be caused by a brick. Lower Ip to .8MA. 8 Pla Survives. Mo monitor drops to 8e14 from middle 15s during the earlier shots. Apparently this is gain changes on the monitor. RXU to -.02 from -.01 at .3s to try to help the railing. Ip to 1 MA. 9 Pla Disrupts at 1.1s. Appears to be caused by an injection. Repeat 10 Pla Disrupts at .52s. Appears to be a VDE. Caused by low chopper TMX voltage. But I did not see it in time for the next shot. ZCUR to -.9 from -.5cm. ZXU to .036 from .05. Try to make more stable vertically. Add more gas .05 to .1 s, keep Mo down. 11 Pla Good shot, high density ramp-down sharkfin. Flat-top: ne0=2e20. Still lots of little MO injections. 12 Pla Repeat for FSP. nl_zmeter to 1. Add gas at .15s. Delay nl_zmeter feedback to .27s. Lower clearin to 0 from .005. RCUR to .664 from .6658. Put ZXU back up to .05m. TF games prove to be a problem. Go back on the timing. 13 Pla Disrupts at .76s. EF2_u rails for rather a long time. VDE. gives us an OUT. Diagnosis of EF2U indicates that it dlearly does not follow the voltage demand after the supply has exceeded the current limit. This is one of these internal integrator problems. Back away from this. Reload 11. Lower Current to 0.8MA. Delay the first half of the sweep to keep EF2 away from the rail. Lower nl_zmeter gain to 2, because the effective gain is larger at higher density. 14 Pla Disrupts at .52s. Horrid disruption recovery shot. Delay the clearin ramp still more. Lower segment 1 gas. 15 PSdud EF3 breaker had pulled out and was not reset. We got +3kA at commutation. 16 Pla EF2s still kiss 4kA at .3s, this corresponds with the end of the OH1 crossover. Keep clearin at -.02 till after .3s. 17 Pla Ef2s now peak at 3300A. Thus we have some clearance at last. This demonstrates that a big part of the problem is that one simply cannot divert the plasma much before .4s without pushing on EF2s. If EF4 were quicker, this would be less of a problem. zxu to .05 late. Ip to 1MA. Clearin to .002 from .005. 18 Pla Fine 19 PSDud Paranay did the EF2 fix diose is the wrong direction. No EF2. 20 Pla Still save on EF2 current. nl_zmeter to 1.3 added a pulse gas 1 (bsidelower) of 60V .4 to .5s. 21 Pla Not much more density. 2.3-2.7e20 central. B-side puff to 100V, .4s to .55s. nl_zmeter to 1.5. 22 Pla Got 2.3-3.0e20. Raise ICEF4 to 2kA to help the EF2s. Raise OH1 Voltage to 175V at shot end to help current droop. Bside puf to 100V .35 to .55s. nlzmeter to 1.7 and ramped earlier. 23 Pla nlzmeter to 2.0 ramped earlier. pulse gas 3 raided in the .2-.3s time. bside puff to .35-.55s 100V. 24 Pla Disrupts at .65s after a big marfe. Ef2 is current railed Phenomenally high voltages seens on OH2U=150v, OHL=170V. and EF1 about 350V! Back way off nlzmeter early, bside to .4-.55s. 25 Pla Good shot but FSP not fired. Some Mo injections. No Yag. 26 Pla Disrupts at .43 s. Brick injection at .405s. Clear on the wide angle TV in the vicinity of H-port. |
| Session Leader Comments | |||
| Jun 1 1995 08:15:41:740AM | Bruce Lipschultz | Run 950601
Engineering operator: V. Bertolino Phyics operator: I. Hutchinson Session leader: BLip mp #105: Dependence of Detachment Threshold and Radial Extent on Plasma Current & q. During this run we plan to try to achieve the 1 MA flat-plat plasmas required for this mp. The plan is to start at 800 kA to tuneup and cleanup from yesterdays vent. We will probably take data at several different densities at 800 kA (5-10 shots). Then, we will switch to 1 MA and try for the same density scan. If this proves to be impossible then we will switch to part 2 of this mp, the q scan. | |
| Jun 1 1995 08:53:12:660AM | Bruce Lipschultz | Run 950601
Engineering operator: V. Bertolino Phyics operator: I. Hutchinson Session leader: BLip mp #105: Dependence of Detachment Threshold and Radial Extent on Plasma Current & q. During this run we plan to try to achieve the 1 MA flat-plat plasmas required for this mp. The plan is to start at 800 kA to tuneup and cleanup from yesterdays vent. We will probably take data at several different densities at 800 kA (5-10 shots). Then, we will switch to 1 MA and try for the same density scan. If this proves to be impossible then we will switch to part 2 of this mp, the q scan. | |
| Jun 1 1995 09:41:07:740AM | 950601001 | Bruce Lipschultz | shot 1: 800 kA. No interferometer so the density feedback is on the
raw bremsstrahlung signal. The estimated density is nl04=1.e20. The sweep went alright around outer div. probe 8. |
| Jun 1 1995 09:50:31:670AM | 950601002 | Bruce Lipschultz | shot 2: disruption shortly after inversion. Otherwise the sweep is
slightly better. Again the density roughly equivalent to nl04=1., in this case we got the Thomson - central density of 1.6e20. |
| Jun 1 1995 10:09:01:700AM | 950601003 | Bruce Lipschultz | shot 3: 800 kA, no disruption. Ne0 (YAG) varies from 1.5 - 2 during shot.
Sweep has been slowed down but still covers full range around probe 8. Probe 9 still working (knock on wood!). |
| Jun 1 1995 10:22:51:220AM | 950601004 | Bruce Lipschultz | shot 4: same shot but with FSP scan. We are experiencing strong Mo
injections every shot. |
| Jun 1 1995 11:02:00:310AM | 950601005 | Bruce Lipschultz | shot 5: 1 MA, no FSP scan or YAG. Unusual shot in that brems. drops
around .7 seconds along with sawteeth stopping. We will repeat with FSP. |
| Jun 1 1995 11:02:09:600AM | 950601005 | Bruce Lipschultz | shot 5: 1 MA, no FSP scan or YAG. Unusual shot in that brems. drops
around .7 seconds along with sawteeth stopping. We will repeat with FSP. |
| Jun 1 1995 11:02:39:790AM | 950601006 | Bruce Lipschultz | shot 6: disruption of unknown origin.
|
| Jun 1 1995 11:14:24:270AM | 950601007 | Bruce Lipschultz | shot 7: disruption at .51 seconds preceded by enormous injection.
|
| Jun 1 1995 11:27:30:240AM | 950601008 | Bruce Lipschultz | shot 8: 800 kA and everything fine. No FSP, domed probes
7 and 9 working! |
| Jun 1 1995 11:45:08:950AM | 950601009 | Bruce Lipschultz | shot 9: 1 MA shot, disruption at 1.1 seconds. FSP scan ok. Ne0 = 1-1.5
e20 over the shot. |
| Jun 1 1995 11:58:33:720AM | 950601010 | Bruce Lipschultz | shot 10: disruption at .52 seconds due to VDE.
|
| Jun 1 1995 11:59:02:830AM | 950601010 | Bruce Lipschultz | shot 10: disruption at .52 seconds due to VDE.
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| Jun 1 1995 12:14:44:120PM | 950601011 | Bruce Lipschultz | shot 11: shot went fine - Ne0=2.e20. No FSP scan. repeat with FSP.
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| Jun 1 1995 12:27:21:410PM | 950601012 | Bruce Lipschultz | shot 12: Ne0=2 - 2.3e20. FSP scan ok.
|
| Jun 1 1995 01:47:38:420PM | 950601013 | Bruce Lipschultz | shot 13: STRIKEOUT, 280 kA halo current. There seems to be an enormous
number of problems. At 500 ms the density drops out as the MARFE ends. The gas valve opens wide to compensate however the plasma density does not rise further aggravating problems that have occurred simultaneously with the power supplies. We will back off the programming in a number of areas and try again. |
| Jun 1 1995 01:54:45:960PM | 950601013 | Bruce Lipschultz | shot 13: STRIKEOUT, 280 kA halo current. There seems to be an enormous
number of problems. At 500 ms the density drops out as the MARFE ends. The gas valve opens wide to compensate however the plasma density does not rise further aggravating problems that have occurred simultaneously with the power supplies. We will back off the programming in a number of areas and try again. |
| Jun 1 1995 02:10:51:990PM | 950601014 | Bruce Lipschultz | shot 14: disruption
|
| Jun 1 1995 02:11:09:310PM | 950601015 | Bruce Lipschultz | shot 15: dud
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| Jun 1 1995 02:53:50:390PM | 950601016 | Bruce Lipschultz | shot 16: fine at 800 kA. Next shot 1 MA.
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| Jun 1 1995 03:00:53:020PM | 950601017 | Bruce Lipschultz | shot 17: 800 kA, next shot 1 MA
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| Jun 1 1995 03:03:19:780PM | 950601018 | Bruce Lipschultz | shot 18: 1 MA, Ne0=1.6 rising to 2.2e20. No FSP scan.
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| Jun 1 1995 03:17:30:370PM | 950601019 | Bruce Lipschultz | shot 19: dud, power supply turned off.
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| Jun 1 1995 03:32:06:960PM | 950601020 | Bruce Lipschultz | shot 20: Ne0 varies from 2 to 2.7e20, 1 MA, FSP scan.
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| Jun 1 1995 03:51:57:010PM | 950601021 | Bruce Lipschultz | shot 21: Ne0=2.3-2.8e20. FSP scan ok.
|
| Jun 1 1995 04:15:07:440PM | 950601022 | Bruce Lipschultz | shot 22: Ne0 varying from 2.2 - 3.2e20, FSP scan. Looks like beginnings
of detachment during latter part of shot. |
| Jun 1 1995 04:22:03:480PM | 950601023 | Bruce Lipschultz | shot 23: Ne0=2.8-3.8e20. FSP scan ok. Still no clear detachment.
|
| Jun 1 1995 04:28:32:050PM | 950601024 | Bruce Lipschultz | shot 24: disruption at .64 seconds. MARFE early on.
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| Jun 1 1995 04:55:59:920PM | 950601025 | Bruce Lipschultz | shot 25: shot went fine but no FSP scan. The divertor probe data
shows low temperatures on probe 8 (below 5 eV) but very high densities (3e21 m^-3)) such that the pressure is still peaked at the separatrix and no obvious detachment. No Thomson but guess Ne0 > 3e20 by end of shot. |
| Jun 1 1995 04:56:47:830PM | 950601026 | Bruce Lipschultz | shot 26: disruption due to very large injection shortly after .4 seconds.
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| Physics Operator Comments |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:38:55:920AM | Plasma | Ok | |
| 2 | 09:35:58:430AM | Plasma | Ok | |
| 3 | 09:50:51:790AM | Plasma | Ok | |
| 4 | 10:12:04:640AM | Plasma | Ok | |
| 5 | 10:28:31:690AM | Plasma | Ok | |
| 6 | 10:50:30:930AM | Plasma | Ok | |
| 7 | 11:03:55:120AM | Plasma | Ok | |
| 8 | 11:15:54:710AM | Plasma | Ok | |
| 9 | 11:29:03:990AM | Plasma | Ok | |
| 10 | 11:45:36:950AM | Plasma | Ok | |
| 11 | 12:00:19:970PM | Plasma | Ok | |
| 12 | 12:16:07:400PM | Plasma | Ok | |
| 13 | 12:31:26:140PM | Plasma | Ok | |
| 14 | 01:50:08:160PM | Plasma | Ok | |
| 15 | 02:04:07:100PM | Plasma | Ok | |
| 16 | 02:16:50:630PM | Plasma | Ok | |
| 17 | 02:32:25:600PM | Plasma | Ok | |
| 18 | 02:47:34:810PM | Plasma | Ok | |
| 19 | 03:04:20:590PM | Plasma | Ok | |
| 20 | 03:15:17:200PM | Plasma | Ok | |
| 21 | 03:31:03:940PM | Plasma | Ok | |
| 22 | 03:47:31:240PM | Plasma | Ok | ef1 1 SCR not conducting. |
| 23 | 04:03:44:010PM | Plasma | Ok | |
| 24 | 04:19:07:510PM | Plasma | Ok | |
| 25 | 04:37:29:210PM | Plasma | Ok | |
| 26 | 04:49:36:150PM | Plasma | Ok | |