Miniproposals

Miniproposal: 043 Date Filed: 3/31/1994 Title: Effect of edge radiation on divertor detachment First Author: Gary McCracken Session Leader: Gary McCracken (shots 1-31)

Engineering Operator Run Comment

diverter detachment

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:11:790PM

Author: To Be Determined

Session Leader Report for Run 950111 EO Daigle/Bertolino PO J Goetz SL G McCracken The objective of the run was to study the effect of increasing radiation on divertor detachment, as described in Miniproposal 043. A single null diverted discharge was set up with the outer strike point near the bottom of the vertical target plate (probe 2)and a density ramp which was initially from 0.8e20 to 1.8e20 m^-2. An increasing amount of neon was then puffed in successive shots to study the effect on detachment. We initially had early disruptions when the neon was puffed in at 0.3 s. The feedback control of the outer strike point had been turned on to try and maintain the strike point at a constant position during the discharge and it was initially thought that it was this feed-back control was the cause of the disruptions. However the radiation was very high even when quite modest amounts of neon was injected and it turned that this was the cause of the disruptions. When the neon was injected at 0.5 s, after the current flat top had been reached, there were no further problems. Incidentally at one point the gas puff was turned off during the discharge and one of the lowest densities so far achieved on C-Mod , nel04<2e19,was recorded. The measured Zeff reached 30! Starting with shot #011, an increasing amount of neon was injected and the critical density for detachment decreased from about 1.4e20 (near the end of the density ramp) to 0.85e20 m-2, shortly after the neon was injected. With increasing neon the power radiated also increased so that the power crossing the LCFS into the SOL decreased from about 800 kW with no neon, to less than 200 kW with a large neon injection. Shot 023 was the one with the maximum amount of neon without disruption. A number of background shots were run, with no neon. These were notable for having almost zero neon, ie there was much less hold up in the walls than argon. With hindsight it was realised the we should have reduced the starting value of the density ramp and we may well have got detachment at even lower densities. The neon was injected through the upper B-side valve. Plenum pressures from 1.6 to 5 psi were used , but from shot 018 on the pressure was 3 psi. The valve voltage pulselength was varied from 20 to 60 ms. It was found that up to 40 ms comparitively little effect was observed but that there was a very sudden transition between 40 and 60 ms pulse. Good Ne I and Ne VIII signals were obtained on the oma and the McPherson respectively, for most shots. Scanning probe profiles were also taken for many discharges. The last 2 shots 030 and 031 were non standard. For shot 030 a small puff of neon (3 psi, 20ms) was puffed into a discharge at constant density to study the recycling of neon in steady state conditions. The neon reached a maximum and then decayed roughly exponentialy to a steady state level. In the last shot the density was kept constant at 1e20 m-2 and the neon concentration increased throughout the shot by a succession of 20 ms puffs, 50 ms apart. The neon concentration increased in steps resulting in increasing degrees of detachment and then finally in a disruption at 0.8 s.Towards the end of the pulse the radiation exceed the input power. Future studies should examine the effects at even lower densities and also the effect of other impurity gases (eg Ar)as a means of increasing radiation and changing the radial profile of radiation in the main chamber. Shot Summary 001 Good shot, constant density, nel04=8e19 m^-2, no neon 002 Good shot, density ramp from 1e20 to 2e20 no neon 003 Dud 004 Good shot, density ramp from 0.8e20 to 1.8e20, no neon 005 neon puff 5 psi, 20 ms at 0.3 s. No D2 puff due to feedback failure nel04<2e19, Zeff = 30 maximum 006 Disrupted at 0.47 s 007 Fizzle 008 Disrupted at o.47 s 009 Strike point control turned off, still disrupted. 010 Fizzle 011 No neon in. Detachment at about 0.7 s, but the situation is confused because the strike point is moving up the target plate 012 Neon injection for 20 ms at 0.5 s. Plenum pressure 1.6 psi. Detachment at ~0.6 s on probe 3, but strike point still moving during the discharge 013 Neon injection for 20 ms at 0.5 s. Plenum pressure 1.6 psi. Detachment at ~0.7 s, Strike point better Some of the parameters of the more interesting shots are shown below. The power into the SOL is the lowest value occurring during the shot. The value at detachment is usually higher ~ 600 kW. In some cases, with high neon injection, detachment occurs very early and then the plasma reattaches, possibly due to the decay in the neon level. It then detaches again at higher density, eg shots #020 and 029. Shots #019 and 020 had 5 mm outer gap and are atypical. Neon Time of detachment Density at detachment Power into SOL s nel04 kW 013 1.6psi ,20ms 0.7 1.34 710 014 1.6psi ,30ms 0.7 1.34 670 015 1.6psi ,50ms 0.7 1.35 560 016 5.0psi ,30ms 0.54 1.03 260 017 no neon 0.77 1.41 770 018 3.0 psi ,20ms 0.89 1.39 705 019 3.0 psi ,30ms 0.86 1.37 020 3.0 psi ,40ms 0.55 & 0.81 0.89 & 1.23 340 021 3.0 psi ,30ms 0.88 1.34 670 022 3.0 psi ,40ms 0.81 1.24 640 023 3.0 psi ,60ms 0.56 0.89 <200 024 3.0 psi ,50ms 0.56 0.87 400 025 no neon 800 026 dud 027 3.0 psi ,40ms 0.81 1.28 600 028 3.0 psi ,50ms 0.56 0.89 600 029 3.0 psi ,45ms 0.56 & 0.83 0.89 &1.28 600 030 3.0 psi ,20ms 720 031 5 X3.0 psi ,20ms 0.6 & 0.67 0.96 & 0.96 800 to 0

Physics Operator Summaries

Entered: Jul 7 2004 04:36:52:850PM

Author: To Be Determined

Physics operator summary for 950111 EO: Daigle/Bertilino PO: Goetz SL: McCracken Run 950111 was in support of Mini-Proposal #043 - Effect of edge radiation on divertor detachment. The goal of this mini-proposal is to investigate the effect of enhanced radiation on the critical density for detachment and study the effect of high edge impurity concentrations on the molybdenum influx (MoI) and central molybdenum (MoXXXI) concentration. Program for this run: - Setup a lower SN discharge with the outer strike point halfway up the outer plate and with parameters: Ip=0.8MA; Nel_04=0.8e20; outer gap > 1.5cm; and inner gap > 1.5cm - Raise the density linearly during the discharge to cause detachment of the divertor - Puff neon through the valve at B_SIDE_UPPER to observe the changes in detachment characteristics ( if any ) and observe the various charge states of molybdenum - Repeat with argon (if there is time) These goals were not quite accomplished as there was not time to get to the argon puffing. Various amounts of neon were puffed into discharges of varying density. See the SESSION_LEADER summary for a more detailed description of the physics results. Some things discovered today: 1) Be careful when puffing impurities into a non-diverted discharge, the plasma will readily accept the impurity. This leads to a radiation induced disruption which is easily mistaken for an EF2 rail problem. 2) The startup scenario used today led to a rubbing of the nose between 0.4 and 0.5 sec. This appears to have only liberated deuterium and doesn't seem to lead to an increase in moly influx. So maybe some attention needs to be payed to early control of the x-point position. 3) At the higher densities run today, the discharge disrupted during ramp-down. Playing the standard tricks with RCUR and CLEARIN didn't seem to help. Some attention should be devoted to developing a rampdown scheme that is independent of plasma current and density. 4) The STRKPSI controller was used today with some success ( once the physics operator finally realized what 0. meant - 0. is the nominal strike point, around probe O4). The strike point was held quite constant, which is important in trying to determine detachment effects across the divertor plate. Engineering and computing today: OH2L had two comm. faults today - one after a discharge and one during precharge. Otherwise, a good day. Once again a PCS bug was uncovered. When the wires were shuffled to bring the STRKPSI controller into the segment 2 that was in use, the unlinking was not performed correctly. This resulted in the STRKPSI waveform being written into the NL_04 waveform and the resulting shot had a density approaching zero ( as requested ). Scorecard: 31 shots = 27 plasmas + 3 fizzles + 1 p.s. dud Shot summary for Run 950111 Reload of 950110032 Changes to shot 950110032: NL_04 draw to 0.8e20 Shot change result ____ _____ ______ 1 plasma - 0.8MA - good rampdown nl_04=0.8e20 2 draw nl_04 ramp from 0.8e20 @ 0.3 plasma - 0.8MA, but drooping to 2.0e20 @ 0.95 disrupts at 1.3sec from a modified shark fin nl_04 ramps to 2.0e20 3 density ramp to 1.8e20 fizzle - nothing out of the ramp up Ip waveform ordinary slow down RCUR and CLEARIN ramps 4 P_0=1.5e-5 plasma - disr @ 1.4 - disr@1.4 outer strike point drifting up 5 move NL_04 to wire 14 and STRKPSI plasma - disr. @ 1.44 to wire 9 in segment 2 outer strike better enable B_SIDE_UPPER nl_04 < 0.2e20 due to PCS bug 6 repair NL_04 waveform plasma - disr. @ 0.45 P_0=1.6e-5 EF2's on the rail STRKPSI=-.0011 7 stairstep on P gain of STRKPSI fizzle 8 P_0=1.5e-5 plasma - disr. @ 0.46 EF2's on the rail 9 turn off gain on STRKPSI controller plasma - disr. @ 0.47 blame it on the neon 10 remove hybrid enable from B_SIDE_UPPER fizzle 11 no changes plasma - disr. @ 1.38 12 P gain on STRKPSI on @ 0.5 plasma - disr. @ 1.38 pressure in B_SIDE_UPPER = 1.6PSIA STRKPSI was still off hybrid enable B_SIDE_UPPER PG2 = 100Vx.02sec @ 0.5sec 13 turn on STRKPSI P gain plasma - disr. @ 1.38 outer strike still moving 14 STRKPSI=-.00125 plasma - disr @ 1.36 PG2 = 100V x .03sec outer strike still moving 3cm 15 P gain on ZXL=2.5 @ 0.5sec plasma - disr. @ 1.34 PG2 = 100V x .05sec outer strike o.k. @ 0.9sec 16 PG2=100Vx.02sec and pressure = 5.0PSIA plasma - disr @ 1.24 STRKPSI = -.0011 all time strike point terrible 17 disable B_SIDE_UPPER plasma - disr @ 1.39 STRKPSI=-1e-4 - P gain=6 RXL=-.01 - P gain = 1 ZXL=-.005 - P gain = 3 18 nl_04 ramp from 0.6e20 to 1.5e20 plasma - disr. @ 1.30 enable B_SIDE_UPPER with 3.1 PSIA strike point good after 0.65sec 19 PG2=100Vx.03sec plasma - disr. @ 1.32 RCUR=.667 no EFIT 20 PG2=100Vx.04sec plasma - disr. @ 1.28 RXL gain=2 @ 1.0sec and STRKPSI gain outer gap is 0.5cm!! off @ .95 21 RCUR=0.6655 plasma - disr. @ 1.33 PG2=100Vx.03sec back to where we were on 018 22 PG2=100Vx.04sec plasma - disr. @ 1.30 23 PG2=100Vx.06sec plasma - disr. @ 1.28 24 PG2=100Vx.05sec plasma - disr. @ 1.28 25 disable B_SIDE_UPPER plasma - disr. @ 1.33 26 PG2=100Vx.04sec and hybrid enable power supply dud OH2L comm. fault 27 no changes plasma - disr. @ 1.29 28 PG2=100Vx.05sec plasma - disr. @ 1.30 29 PG2=100Vx.045sec plasma - disr. @ 1.29 30 NL_04=1.0e20 from 0.5 to 0.95sec plasma - disr. @ 1.35 PG2=100Vx.02sec no div. detachment 31 [PG2=100Vx.02sec] x 7 pulses plasma - disr. @ 0.79 starting at 0.5sec every .07sec due to too much neon

Session Leader Comments
Jan 11 1995 08:32:59:840AM		Gary McCracken	Objective: Mini-Proposal#043: To investigate the effect of enhanced radiation on the critical density for detachment. To study the effect of high edge impurity concentrations on the Mo influx (MoI) and central Mo concentration Run Plan: Set up a single null diverted discharge with the outer strike point about probe 6 on the outer target. Divert at 0.3 s and arrange a density ramp with the feedback control to obtain detachment at the end of the ramp. Then in successive discharges puff in neon at a gradually increasing levels to try and induce detachment at lower density. The neon puff will be for a short pulse at 0.3 s from the B side top valve, similar to the HIREX argon pulse. If time permits we will use argon in the same mode. The intention is to go to close to 100% radiation, so that power into the SOL is a minimum.
Jan 11 1995 06:21:38:420PM		Gary McCracken	Summary: Overall a successfull day with the main objectives of MP 043 being achieved. By increasing the amount of neon injected in sucessive shots the amount of power radiated was increased and the power into the SOL decreased from about 800 kW to nearly zero. As a result the density for detachment was decreased from nel04= 1.4e20 to at least 1e20. m^-2.
Jan 11 1995 08:59:41:640AM	950111001	Gary McCracken	Objective: Mini-Proposal#043: To investigate the effect of enhanced radiation on the critical density for detachment. To study the effect of high edge impurity concentrations on the Mo influx (MoI) and central Mo concentration Start with a repeat of yesterdays shot #950110032. Good shot. nel04=8.2e19 m-2 from 0.3 - 0.9 s. H-mode started at 0.91 s. Very clean, no ELMS. Nice, but we hope that it will go away when we ramp the density. Attempt density ramp in the next shot
Jan 11 1995 09:19:15:960AM	950111002	Gary McCracken	Objective: Mini-Proposal#043: To investigate the effect of enhanced radiation on the critical density for detachment. To study the effect of high edge impurity concentrations on the Mo influx (MoI) and central Mo concentration Good shot. Density ramp up to 2e20 at 0.95 s. Divertor detachment occurs at about 0.64 s. This is a bit early since we want toreduce the density of detachment further with the neon. We will slow down the density ramp in the next shot. Incidentally the FMP probes are configured for disruption. The domed probes however show the detachment
Jan 11 1995 09:33:05:180AM	950111003	Gary McCracken	Dud
Jan 11 1995 10:00:36:740AM	950111004	Gary McCracken	Good shot. Density rose to 1.8e20 at 0.93 s. The detachment occurred on probe 6 around 0.8 s, but the detachment was more gradual than in the previous shot. This seems to be because the outer strike point is moving up the target plate. We will try and control the strike point better in the next shot. .
Jan 11 1995 10:19:25:880AM	950111005	Gary McCracken	Poor shot. After trying to reset the strike point the density feedback did not work. Low density and X rays. We had put in a small test neon pulse at 0.3 s. 5 psi. Valve opened but no direct evidence that the neon went in The strike point position was much better.
Jan 11 1995 10:38:53:340AM	950111006	Gary McCracken	Disruption at 0.47 s. No obvious reason why. Try again
Jan 11 1995 10:45:31:210AM	950111007	Gary McCracken	Fizzle
Jan 11 1995 11:08:42:650AM	950111008	Gary McCracken	Disrupted at 0.47 s. Perhaps due to the strike point control
Jan 11 1995 11:21:04:360AM	950111009	Gary McCracken	Disrupted at 0.47 s. Strike control turned off so it can't be that. Radiated power is exceeding the input power so possibly it is due to the neon injection. We will turn this off for the next shot.
Jan 11 1995 11:27:24:050AM	950111010	Gary McCracken	Fizzle
Jan 11 1995 11:48:09:120AM	950111011	Gary McCracken	No neon injected. Good shot. Detached at 0.72 s, but the strike point is now moving again. We are really back to shot 004. Next shot put in neon at 0.5 s with 1.6 psi pressure in the plenum
Jan 11 1995 12:07:03:320PM	950111012	Gary McCracken	Good shot. Neon injected at 0.5 s with 1.6 psi pressure in the plenum. However detachment has not occurred any earlier. Also there is still a problem with the strike point moving. Lastly there is a problem with the McPherson which is not giving any signal. Since this neon signal is critical to the measurements we have decided to have brief cell access to see if the problem with the McPherson can be fixed. The fault was found and rectified.
Jan 11 1995 12:25:11:610PM	950111013	Gary McCracken	Good shot. Neon again injected at 0.5 s with 1.6 psi pressure in the plenum. However detachment has not occurred any earlier. We now have good neon signals on the McPherson and on the oma We will increase neon for the next shot.
Jan 11 1995 12:41:18:200PM	950111014	Gary McCracken	Good shot. Neon again injected at 0.5 s with 1.6 psi pressure in the plenum, but increaased the neon pulse width from 20 to 30 ms. Detachment now occurring at about 0.7 s . Neon signals on the McPherson and on the oma are up nearly a factor 2 We will increase neon again for the next shot.to 50 ms pulse
Jan 11 1995 01:01:09:230PM	950111015	Gary McCracken	Good shot. Neon again injected at 0.5 s with 1.6 psi pressure . Increased the neon pulse width again from 30 to 50 ms. Detachment now occurring a little earlier but it is hard to define exactly when it occurs . Neon signals on the McPherson and on the oma are up nearly another factor 2. Power into the SOL is down from about 680 kW to 580 kW. We will increase neon again for the next shot.
Jan 11 1995 01:26:20:720PM	950111016	Gary McCracken	Neon again injected at 0.5 s but with pressure up to 5 psi Decreased the neon pulse width again from 50 to 30 ms so neon in should be similar to the previous shot. In fact the amount of neon was up a factor of 3 according to the McPherson Detachment now occurring at 0.54 s . The power radiated in the core is going up from 0.55 MW to 1.3 MW maximum and it is then falling slowly. The power into the SOL is now down to about 300 kW. Unfortunately we are having some problems with the equilibrium and the last shot was a slot divertor for a while
Jan 11 1995 01:41:46:280PM	950111017	Gary McCracken	Neon off. Good shot. Detachment occurs at about 0.77 s. Power into the SOL is back up to 770 kW The neon has completely disappeared in the McPherson giving us a good background. Much improved stike point stability
Jan 11 1995 01:59:32:040PM	950111018	Gary McCracken	Neon on again. Pressure 3 psi pulse width 20 ms. Reduced density ramp rate. Good shot.Density now reaching a maximum of 1.5e20 at 0.95 s. Detachment now occurring later, about 0.88 s. About 700 kW into the SOL G
Jan 11 1995 02:14:21:060PM	950111019	Gary McCracken	Neon increased. Pressure 3 psi pulse width 30 ms. Good shot. Detachment now about 0.86 s Power into the SOL not known, EFIT did not run G
Jan 11 1995 02:32:01:970PM	950111020	Gary McCracken	Neon increased again. Pressure 3 psi, pulse width 40 ms. Good shot. Detachment now about 0.81 s Power into the SOL is 370 kW. However the outer gap has been reduced to 5mm
Jan 11 1995 02:46:35:200PM	950111021	Gary McCracken	Neon reduced to repeat shot 019. Pressure 3 psi, pulse width 30 ms. Outer gap put back to the value in 018 Good shot. Detachment at 0.88 s Power into the SOL is 640 kW. Outer gap now back to 20 mm and inner gap is 13 mm
Jan 11 1995 02:59:10:090PM	950111022	Gary McCracken	Neon Pressure 3 psi, pulse width 40 ms. Good shot. Detachment difficult to see. Power into SOL is 650 kW
Jan 11 1995 03:18:11:750PM	950111022	Gary McCracken	Neon Pressure 3 psi, pulse width 60 ms. Good shot. Detachment has jumped to much earlier time about 0.56 s Power into SOL drops to less than 200 kW around 650 ms. The amount of neon seems to be very critical at this level
Jan 11 1995 03:17:46:620PM	950111023	Gary McCracken	Neon Pressure 3 psi, pulse width 60 ms. Good shot. Detachment has jumped to much earlier time about 0.56 s Power into SOL drops to less than 200 kW around 650 ms. The amount of neon seems to be very critical at this level
Jan 11 1995 03:24:47:650PM	950111024	Gary McCracken	Neon Pressure 3 psi, pulse width 50 ms. Good shot. Detachment still at earlier time about 0.56 s Power into SOL drops to 400 ms just after detachment and then rises again to 600 kW by 700 ms
Jan 11 1995 03:35:53:280PM	950111025	Gary McCracken	No Neon Good shot. Just hardly get to detachment by the end of the density ramp at 0.95 s Power into SOL was 800 kW
Jan 11 1995 04:14:59:840PM	950111027	Gary McCracken	Neon set 3 psi 40 ms similar to shot 022 Delay due to engineering problems. However when it came it was a good shot. Detachment at about 0.81 s, similar to shot 022. Power into SOL = 600 kW Increase neon pulse to 50 ms in next shot
Jan 11 1995 04:31:34:920PM	950111028	Gary McCracken	Neon set 3 psi 50 ms Detachment at about 0.56 s on the lower probes from about probe 5 down. Thus the behaviour is pretty reproducible with a sudden change of the detachment between a 40 and a 50 ms neon pulse. However it appears to reattach, probably due to decay of the neon with time Power into SOL = 570 kW . This is not as low as last time with 50 ms pulse
Jan 11 1995 04:47:57:470PM	950111029	Gary McCracken	Neon set 3 psi 45 ms Detachment at about 0.56 s It then reattaches and detaches again at about 0.8 s, similar to the lower neon injection pulses Power into SOL = 580 kW .
Jan 11 1995 05:01:13:870PM	950111030	Gary McCracken	Neon set 3 psi 20 ms. Constant plasma density at 1e20 to study the recycling properties of the neon. Good shot Got nice data on the McPherson with the neon decaying to a constant level Power into SOL = 720 kW .
Jan 11 1995 05:27:01:310PM	950111030	Gary McCracken	Constant plasma density at 1e20 Neon injected in a succession of 20 ms pulse every 50 ms to try and induce detachment at constant density by an increasing neon concentration. This worked well with the neon brightness going up almost linearly to the highest value of the day. Plasma detached at 677 ms and disrupted at 800 ms. The density increased slightly at detachment but remained fairly constant. The power radiated increased almost exponentially from about 0.5 s and exceeded the power in after 0.77 s.

Physics Operator Comments
Jan 11 1995 08:14:43:420AM		John Goetz	Today's run is in support of MiniProposal #043 - Effect of edge radiation on divertor detachment. The run will be divided into segments as follows: 1 - obtain a lower SN plasma with outer strike point about halfway up the outer plate and parameters Ip=0.8MA; nl04=0.8e20; inner gap>1.5cm; outer gap>1.5cm 2 - do density ramps until detachment is observed 3 - puff neon through B_SIDE_UPPER and observe changes in detachment characteristics 4 - repeat with argon To achieve these goals, the discharge obtained on 950110032 will be used as the starting point. The only change to be made will be to draw the NL_04 waveform as 0.8e20.
Jan 11 1995 09:00:39:460AM	950111001	John Goetz	Shot 950111001: Start from 950110032 and draw NL_04 as 0.8e20 Plasma - ramps all the way down nl_04=0.82e20 For shot 002: draw nl_04 ramp from 0.8e20 @ 0.3 to 2.0e20 @ 0.95
Jan 11 1995 09:19:04:170AM	950111002	John Goetz	Shot 950111002: Plasma - disrupts at 1.31 (some sort of modified shark fin) density ramps to 2.0e20 divertor detachment observed around 0.65sec For shot 003: density ramp to 1.8e20 ramp up Ip waveform to -.85MA slow down RCUR and CLEARIN ramps
Jan 11 1995 09:37:14:900AM	950111003	John Goetz	Shot 950111003: fizzle - nothing untoward - disruption related?! For shot 004: drop fill pressure to 1.5e-5
Jan 11 1995 10:03:12:940AM	950111004	John Goetz	Shot 950111004: plasma - disr @ 1.40sec - Ip=0.8MA and rising slightly outer strike point is drifting up the plate and makes it difficult to diagnose the divertor detachment For shot 005: move NL_04 to wire 14 in segment 2 and move STRKPSI from wire 9 in segment 3 to wire 9 in segment 2 enable B_SIDE_UPPER (for neon puff)
Jan 11 1995 10:20:50:170AM	950111005	John Goetz	Shot 950111005: plasma - disr @ 1.44sec - Ip=0.8MA and rising slightly outer strike point much better behaved nl_04 < 0.2e20 because of PCS bug related to the wire switching performed for this shot For shot 006: fix NL_04 waveform P_0=1.6e-5 STRKPSI=-.0011 (to help with the strike point)
Jan 11 1995 10:37:19:300AM	950111006	John Goetz	Shot 950111006: plasma - disr @ 0.45sec EF2's stay on the rail instead of just kissing the rail is it related to STRKPSI?? For shot 007: stairstep on P gain of STRKPSI
Jan 11 1995 10:54:06:830AM	950111007	John Goetz	Shot 950111007: fizzle For shot 008: P_0=1.5e-5
Jan 11 1995 11:05:17:930AM	950111008	John Goetz	Shot 950111008: plasma - disr. @ 0.46sec - EF2's on the rails For shot 009: turn off gain on STRKPSI controller
Jan 11 1995 11:29:26:630AM	950111009	John Goetz	Shot 950111009: plasma - disr. @ 0.47sec - EF2's on the rails blame it on the neon For shot 010: turn off B_SIDE_UPPER hybrid enable
Jan 11 1995 11:32:02:450AM	950111010	John Goetz	Shot 950111010: fizzle - no bounce For shot 011: no changes
Jan 11 1995 11:49:17:680AM	950111011	John Goetz	Shot 950111011: plasma - high density disr. @ 1.38 divertor detachment @ 0.72 but outer strike point is moving For shot 012: P gain on STRKPSI stairstep on @ 05.sec to 0.5 @ 0.6sec PULSE_GAS_2 waveform is 100V x .02sec @ 0.5sec pressure in B_SIDE_UPPER = 1.6PSIA and hybrid enable
Jan 11 1995 12:06:10:710PM	950111012	John Goetz	Shot 950111012: plasma - high density disr. @ 1.38 divertor detachment @ 0.72 but outer strike point is moving STRKPSI was not turned (must not have hit o.k.) For shot 013: STRKPSI P gain=0.5 @ 0.6sec
Jan 11 1995 12:29:21:100PM	950111013	John Goetz	Shot 950111013: plasma - high density disr. @ 1.38 outer strike still moving but not as much NeVIII seen on McP and NeI seen on OMA For shot 014: STRKPSI = -.00125 PG2 = 100V x .03sec
Jan 11 1995 12:41:39:960PM	950111014	John Goetz	Shot 950111014: plasma - high density disr. @ 1.36 outer strike still moving For shot 015: lower P gain on ZXL to 2.5 @ 0.5sec PG2 = 100V x .05sec
Jan 11 1995 01:02:47:890PM	950111015	John Goetz	Shot 950111015: plasma - high density disr. @ 1.34 outer strike starts out in the wrong place ends up o.k. @ 0.9sec For shot 016: PG2 = 100V x .02sec and P(B_SIDE_UPPER)=5.0PSIA
Jan 11 1995 01:29:21:080PM	950111016	John Goetz	Shot 950111016: plasma - high density disr. @ 1.24 outer strike on the floor, then drifts up For shot 017: disable B_SIDE_UPPER STRKPSI=-1E-4 - P gain = 6 RXL = -.01 - P gain = 1 ZXL = -.005 - P gain = 3
Jan 11 1995 01:47:22:710PM	950111017	John Goetz	Shot 950111017: plasma - high density disr. @ 1.39 outer strike well controlled - only moves by 1cm no neon For shot 018: enable B_SIDE_UPPER with P(B_SIDE_UPPER)=3.1PSIA nl_04 ramp from 0.6e20 to 1.5e20
Jan 11 1995 02:00:09:190PM	950111018	John Goetz	Shot 950111018: plasma - high density disr. @ 1.30 outer strike well controlled - only oscillates a bit after 0.65s For shot 019: RCUR=.667 (inner gap is too small) PG2=100Vx.03sec
Jan 11 1995 02:14:41:580PM	950111019	John Goetz	Shot 950111019: plasma - high density disr. @ 1.32 For shot 020: PG2=100Vx.04sec RXL gain = 2 @ 1.0sec and STRKPSI gain off @ .95 ( the plasma has been rubbing the nose around 1.0 sec)
Jan 11 1995 02:32:37:210PM	950111020	John Goetz	Shot 950111020: plasma - high density disr. @ 1.28 inner gap still rather small and outer gap is 0.5cm!! For shot 021: PG2=100Vx.03sec RCUR=0.6655 (go back to 018)
Jan 11 1995 02:45:09:360PM	950111021	John Goetz	Shot 950111021: plasma - high density disr. @ 1.33 gaps back to where they were - restart the neon scan For shot 022: PG2=100Vx.04sec
Jan 11 1995 02:58:24:360PM	950111022	John Goetz	Shot 950111022: plasma - high density disr. @ 1.30 For shot 023: PG2=100Vx.06sec
Jan 11 1995 03:10:31:430PM	950111023	John Goetz	Shot 950111023: plasma - high density disr. @ 1.28 clear divertor detachment For shot 024: PG2=100Vx.05sec
Jan 11 1995 03:20:52:080PM	950111024	John Goetz	Shot 950111024: plasma - high density disr. @ 1.28 clear divertor detachment For shot 025: disable B_SIDE_UPPER hybrid enable
Jan 11 1995 03:32:34:740PM	950111025	John Goetz	Shot 950111025: plasma - high density disr. @ 1.33 background shot - no detachment For shot 026: PG2=100Vx.04sec and hybrid enable B_SIDE_UPPER
Jan 11 1995 03:59:50:460PM	950111026	John Goetz	Shot 950111026: power supply dud - OH2L comm. fault during precharge For shot 027: no changes
Jan 11 1995 04:11:33:870PM	950111027	John Goetz	Shot 950111027: plasma - high density disruption @ 1.29 divertor detachment For shot 028: PG2=100Vx0.05sec
Jan 11 1995 04:24:57:470PM	950111028	John Goetz	Shot 950111028: plasma - high density disruption @ 1.29 divertor detachment right after neon comes in For shot 029: PG2=100Vx0.045sec
Jan 11 1995 04:41:25:480PM	950111029	John Goetz	Shot 950111029: plasma - high density disruption @ 1.29 local divertor detachment For shot 030: PG2=100Vx0.02sec nl_04=1e20 from 0.5 to 0.95
Jan 11 1995 04:56:46:260PM	950111030	John Goetz	Shot 950111030: plasma - high density disruption @ 1.35 no divertor detachment For shot 031: PG2=[100Vx0.02sec] x 7 pulses - starting at 0.5sec and coming every 0.07sec
Jan 11 1995 05:16:03:880PM	950111031	John Goetz	Shot 950111031: plasma - radiative disruption @ 0.79 divertor detachment @ 0.67sec plasma survives until the fourth neon puff

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:48:43:230AM	Plasma	Ok	No Faults
2	09:01:15:950AM	Plasma	Ok	No Faults.
3	09:21:31:370AM	Plasma	Ok	No Faults.
4	09:40:01:880AM	Plasma	Ok	No Faults.
5	10:03:21:900AM	Plasma	Ok	No faults.
6	10:22:04:590AM	Plasma	Ok	No faults.
7	10:41:50:170AM	Plasma	Ok	No faults.
8	10:54:57:010AM	Plasma	Ok	No Faults
9	11:08:35:510AM	Plasma	Ok	no faults
10	11:23:02:210AM	Plasma	Ok	No Faults.
11	11:34:00:000AM	Plasma	Ok	No Faults.
12	11:48:46:550AM	Plasma	Ok	No Faults.
13	12:09:22:010PM	Plasma	Ok	No Faults.
14	12:26:35:070PM	Plasma	Ok	No Faults.
15	12:43:26:180PM	Plasma	Ok	no faults
16	01:02:33:140PM	Plasma	Ok	no faults
17	01:28:53:970PM	Plasma	Ok	no faults
18	01:45:13:310PM	Plasma	Ok	no faults
19	02:00:19:730PM	Plasma	Ok	no faults
20	02:14:33:470PM	Plasma	Ok	no faults
21	02:33:32:120PM	Plasma	Ok	No Faults.
22	02:47:18:680PM	Plasma	Ok	No Faults.
23	03:00:22:780PM	Plasma	Ok
24	03:12:17:800PM	Plasma	Ok	no faults
25	03:25:25:320PM	Plasma	Ok	comm faults oh2l, oh1, ef1u after disruption
26	03:42:03:030PM	Plasma	Bad	oh2l comm fault when switch closed
27	04:03:58:160PM	Plasma	Ok	no faults
28	04:18:47:350PM	Plasma	Ok	no faults
29	04:33:10:120PM	Plasma	Ok	no faults
30	04:46:35:950PM	Plasma	Ok	no faults
31	05:04:53:820PM	Plasma	Ok	no faults