| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Jerry Hughes,Martin Greenwald |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Bill Parkin,Gary Dekow |
| Engineering Operator Run Comment |
| MP296 & MP233A; PO:Granetz; SL:Hughes/Hubbard; EO:Dekow/Parkin |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:26:430PM |
| Author: To Be Determined |
| Session Leader Run Summary for Wed 20 June 2001 (AM) MP296: Calibration of Thomson scattering using ECE cutoffs SL: J. HUghes PO: B. Granetz GOAL: Use signal cutoffs from GPC and GPC2 to check the absolute calibrations of the Thomson scattering (TS) system. Plasma density and ECE cutoff density will be changed dynamically during each shot in order to generate clear signal cutoffs. Results will be cross-checked against TCI and visible bremsstrahlung measurements. SUMMARY: Run went less smoothly than expected, but some cutoff data were obtained. Things looked promising early on, but we were ultimately plagued with injection-induced disruptions on several shots, upon application of RF heating. We got multiple L-H and H-L transitions on shots 1 and 2, as expected. However, on the next set of shots, as we attempted a long EDA with B_T sweep, we got either a disruption before L-H, or a series of short-lived ELM-free-like H-modes. Shot 5 produced some good cutoffs, particularly in the third H-mode. After three consecutive disruptions, we ran a limited ohmic L-mode on shot 9, ramping the density through the ECE cutoffs at 3.3 T. This was successful in producing cutoff points across almost the whole profile. We got about 50 data points total from shots 002, 005, and 009, which are suitable for cross-calibration. Corrections to the existing 2001 Thomson data are forthcoming. DETAILS: _____________________________________________________________ Run Plan for 1010620A: MP296 TS/ECE n_e Cross-Calibration PLAN: Configure GPC, GPC2 for 4.7 T operation. .Shot 1 Start with shot 1001215023: 4.5 T, 1 MA, target nl~0.9e20. Apply constant RF at 1-2 MW. Expect multiple L-H transitions, giving several ECE cutoffs in the core plasma. .Shot 2 Lower Ip to 0.8 MA, nl04 to 0.8e20. Raise Bt to 4.8 T. Starting 0.2 s after RF onset, ramp Bt down to 4.5 T and up to 4.8 T at a rate |dB/dt|~1 T/s. .Shots 3-4 Adjust Ip, Bt, nl04 as needed to obtain useful set of ECE cutoffs in H-mode. .Shots 5-6 (if necessary) Adjust GPC2 for 3.3 T operation (as configured for 1010614006). Run ohmic L-mode inner wall limited, 0.8 MA, nl04~1e20. Ramp Bt to 3.3 T and hold, then raise nl04 to 2e20. [If RF unavailable, go to Plan B: .Shots 1-4 Repeat 1000829027 (Ohmic EDA H-mode, 0.8 MA) with GPC2 adjusted for B_0=3.7 T. .Shots 5-6 same as above] RESULTS: Shot 1: Good shot, but got no Thomson data due to the port shutter being closed. RF decent, multiple H-modes. numerous cutoffs on GPC and GPC2. Repeat to get Thomson data. Shot 2: Good shot. Multiple H-modes, and over 20 GPC cutoff points. Can use to check Thomson channels D,G,L,B Shot 3: Injection occurred at .83 s, leading to disruption prior to reaching cutoff. Repeat with minor adjustment to Bt sweep. Shot 4: Shot went as programmed. 5 ELM-free H-modes. Density doesn't reach cutoff prior to H-L transition in any case. So we will try raising the target nl04 to 1e20. Perhaps this will make the H-mode more EDA-like, also. Shot 5: Shot ran well. Got 4 marginal EF/EDA H-modes. Good cutoff data, especially during the 3rd H-mode. On next shot, we will try to get more EDA-like H-modes by lowering Ip to 0.7 MA, while raising the target nl04 to 1.2e20. Cutoff data is better at lower field. We will try starting at 4.5 T and ramp UP to 4.8 T. Shot 6: Killed by injections at 0.67--0.69 s. Target nl04, Ip, Bt looked good, however. Shot 7: Killed by injections at 0.69 s. RF? Bob will back off the density, see if it helps. Shot 8: The injections continue. We will abandon RF and move on to the last part of the run plan, L-mode, inner-wall limited, with nlo4 ramp from 0.8--2.0e20. Shot 9: Ran mostly as programmed. Cutoffs prevalent in both GPC and GPC2. Signals less clear at the edge than in the core, but I think we can use them. Will turn run over to Martin. _______________________________________________________________ |
| Entered: Jul 7 2004 03:49:26:447PM |
| Author: To Be Determined |
| Run Summary for 1010620 MP233a Density limit mechanisms Session Leader - Greenwald Phys Op Granetz Plan: We want to collect more data on the changes in turbulence and transport which have been linked to the density limit. In the previous experiments it was observed that the regime of large coherent fluctuations which normally exists in the far scrape-off, moves inward to the separatrix and intrudes into the closed field line regions as the density limit is reached. We will try to insert the probe more deeply into these plasmas at high densities in order to follow the evolution of the profiles and fluctuations. In particular we will try to assess how far into the main plasma this phenomenon reaches. We will also use this opportunity to obtain more data on the changes in transport that accompany the change in fluctuations. The fast camera will be used to look for any visible changes in the edge turbulence - in particular to watch for progressive movement of the turbulent region as the density is raised. 1000620012 would be a good starting point. As before, the approach will be to produce high density ohmic discharges then to ramp down the plasma current to approach the density limit. This gives us density limit disruptions which are reproducible in time which eases the operation of the fast scanning probe. The B$_T$ programming might need to be altered to allow edge profile measurements until the time of the disruptions. Once the shot is set up, few changes are needed. Results: We made a good start, but this was only half a run and started later than we had planned. We got reproducible density limit disruptions and were able to push the probe in systematically. The probe was inserted at 0.95 sec and the disruptions occurred just after 1.0 sec. The cooling obviously proceeds in past the last closed flux surface. We see the break in profiles, turbulence, auto-correlation function in to about rho = -1 cm. Interesting analysis which should be done: a) plot breakpoint vs n/n_g b) calculate mhd equilibrium with current excluded from cold region c) analyze pci spectra d) look at shots with poloidal detachment near the density limit these seem to shrink in minor radius more or less to keep n/n_g ~ 1 If we get more time we will repeat the experiment with the probe plunge nearer to the density limit. Shots for further analysis: Shot A Probe position (nominal) 1010620014 - 4. mm 1010620016 - 5.7mm 1010620017 - 7.9mm 1010620019 -11. mm 1010620020 -14.2mm |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:13:440PM |
| Author: To Be Determined |
| Physics operator summary for run 1010620 (Wednesday): MP 296 : Thomson calibration using ECE cutoff MP 233A: Density limit mechanisms Session leader: J. Hughes (MP 296)/ M. Greenwald (MP 233A) Physics operator: R. Granetz Engineer: G. Dekow/B. Parkin Summary: The first 9 shots were devoted to MP 296, which was completed with good results. Shot 9 was probably the best shot for that MP. We began MP 233A on shot 10, and got very good "blobby" fluctuation data on the ASP, which was going in well past the separatrix. See the session leader's summary for more physics. The tokamak ran very well - only one fizzle and no duds. The 2.45 GHz ECDC magnetron failed after shot 6. The TCI CO2 laser failed on shot 18. D-antenna was having problems, and CMODA crashed twice. Scorecard: 19 plasmas 1 fizzles 0 duds 0 tests 0 aborted and/or screwed up by computer problems ---------- 20 total ------------------------------------------------------------------------------- Engineering setup: ECDC in D2 overnight prior to run. Be prepared for ECDC in D2 between shots using B-side-upper valve. (Z-meter/bolometer shutter should be closed during ECDC, opened for plasma.) Power systems as on 1001215023. Gas setup: fill B-top with 6 psi of D2 Hybrid enabled (PG4) fill B-side lower with 1 psi of Ar Hybrid enabled (PG1) fill B-side upper with 30 psi of D2 Hybrid DISABLED (PG2) fill C-side with 30 psi of D2 Hybrid enabled (PG3) fill J-bottom with 30 psi of He Hybrid DISABLED (PG5) Enable the following gate valves: ECE, DNB, VUV Run starts at 09:00 and ends at 17:00. ------------------------------------------------------------------------------- RF Setup: Transmitters 1 and 2 should be in run-on by 08:00. We will need 1-2 MW from D and E antennas for MP 296. No RF is needed for MP 233A. ------------------------------------------------------------------------------- Run Plan: MP 296 : Thomson calibration using ECE cutoff We will do this first. In order to promote ECE cutoff, run at 4.5 tesla and high density. Obtain high density by getting into H-mode (possibly with ITB's) with 1-2 MW from D and E antennas. Start from shot 1001215023. Btor, Ip, and ne ramping will probably also be tried. MP 233A: Density limit mechanisms Ramp down Ip to reach the density limit in ohmic plasmas. Expect lots of density-limit disruptions. Start from shot 1000620023. Fluctuation and edge diagnostics should have fast windows during the H-L transition and near the L-mode disruption if possible. ------------------------------------------------------------------------------- Overnight ECDC in D2 was done. Hybrid coldstart done; no errors found Loaded segments 2,3,4 from 1001215023, as per Jerry's instructions, but I changed density feedback to use the TCI instead of the Z-meter. I also zeroed the B-side-upper valve programming, since that's now for between-shot ECDC. DNB is not operating this morning. ------------------------------------------------------------------------------- Shot 01 -- Plasma. Good shot. 1 MA, 4.5 T. Multiple H-modes. Prf=0.78 MW. The Thomson shutter unexpectedly closed, so we will have to repeat this shot. GPC cutoff several times. Next shot: add +5 amps to IC_EF4. No other changes (except have Thomson keep their shutter open). Shot 02 -- Plasma. Good shot. 1 MA, 4.5 T. Multiple H-modes. Prf=1.0 MW (from E only). GPC had one cutoff period. Thomson data OK. Next shot: lower Ip to 0.8 MA, lower target density to nl_04=0.8e20 m-2, raise Btor to 4.8 T, but put in a ramp down to 4.5 T and then back up to 4.8 T, starting at t=0.8 s. Turn on between-shot ECDC. Shot 03 -- Plasma. Disrupted at t=0.86 s due to a big injection at t=0.83 s. Btor ramped from 4.80 to 4.56 T and then back to 4.80 T. Target density was nl_04=0.8e20 m-2, as desired. Prf=1.2 MW, mostly from E. The D antenna system is not doing well. Next shot: repeat with faster Btor ramp. ECDC in D2 is going between shots. Shot 04 -- Plasma. Good shot. Ip, Btor, and nl_04 are as requested. Multiple ELMfree H-modes. Prf=1.3 MW, mostly from E. GPC didn't show clear cutoffs. H/D=5-11%. Next shot: raise density to nl_04=1.0e20 m-2. ECDC in D2 is going between shots. Shot 05 -- Plasma. Good shot. Got the higher target density. Multiple H-modes. Prf=1.5 MW. Jerry got good cutoff data. H/D=5-10%. Next shot: Lower Ip to 0.7 MA, raise target nl_04 to 1.2e20 m-2, lower Btor to 4.5 T, but include a ramp up to 4.8 T and back down to 4.5 T (with same timing as previous shots). ECDC in D2 is going between shots. Shot 06 -- Plasma. Disrupted at t=0.69 s due to an impurity injection. Got the requested Ip, Btor, and nl_04. Next shot: try the same thing again. ECDC 2.45 GHz magnetron has failed. There will be no more ECDC during the run. Shot 07 -- Plasma. Disrupted at t=0.69 s again. Next shot: try again, but lower nl_04 slightly to 1.1e20 m-2. Shot 08 -- Plasma. Disrupted at t=0.83 s. Give up on this. Next shot: set Btor=3.3 T (92 kA), Ip=0.8 MA, nl_04 ramping from 0.8 to 2.0e20 m-2, inner wall limited (reduce RCUR by 1.0 cm and CLEARIN by 2.0 cm). Long delay due to CMODA computer crash. Shot 09 -- Plasma. Good ohmic L-mode shot. Ip=0.76 MA, Btor=3.40 T, nl_04 ramped up to 1.5e20 m-2. GPC was solidly cutoff. Plasma was on the line between limited and diverted. End of MP 296: CMODA crashed again. Switch to MP 233A: Next shot: load shot 1000620012, an ohmic, diverted, high-density disruption shot. Set fast windows on Mirnov and x-rays. Shot 10 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.04 s. Outer gap = 8 mm. Inner gap = 15 mm. Next shot: increase outer gap to 15 mm and inner gap to 20 mm. (reduce RCUR by 1 mm and increase CLEARIN by 5 mm) Shot 11 -- Plasma. Disrupted at t=0.28 s, possibly because the CLEARIN change started too early in the shot. Next shot: undo change to CLEARIN for the early part of the shot. Shot 12 -- Fizzle. Next shot: no changes Shot 13 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Outer gap = 10-15 mm. Inner gap = 20 mm. Next shot: no changes Shot 14 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Got good probe data. ASP sees blobby fluctuations well inside of the separatrix. Next shot: no PCS changes. Brian will send the ASP in farther. Shot 15 -- Plasma. Disrupted early at t=0.30 s due to momentary excessive elongation and vertical instability. Next shot: reduce CLEARIN early in the shot again. Reduce pre-fill by 2 ms for post-disruption recovery. Shot 16 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.02 s. Still showed signs of vertical instability around t=0.27 s. Good probe data. Next shot: add 2 ms back to the pre-fill puff. Shot 17 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Good probe data. Next shot: no changes Shot 18 -- Plasma. TCI feedback failed. CO2 laser was off. No gas fueling --> low density --> late disruption, high edge temperatures --> nearly cooked the ASP. Next shot: no PCS changes Cell access for Jim Irby and Rick Murray to fix the TCI. Shot 19 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.04 s. Good probe data. Next shot: no changes Shot 20 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.02 s. Good probe data. End of run |
| Session Leader Comments | |||
| Jun 20 2001 08:32:13:653AM | Jerry Hughes | Run Plan for 1010620A: MP296 TS/ECE n_e Cross-Calibration Goal: Use signal cutoffs from GPC and GPC2 to check the absolute calibrations of the Thomson scattering (TS) system. Plasma density and ECE cutoff density will be changed dynamically during each shot in order to generate clear signal cutoffs. Results will be cross-checked against TCI and visible bremsstrahlung measurements. PLAN: Configure GPC, GPC2 for 4.7 T operation. .Shot 1 Start with shot 1001215023: 4.5 T, 1 MA, target nl~0.9e20. Apply constant RF at 1-2 MW. Expect multiple L-H transitions, giving several ECE cutoffs in the core plasma. .Shot 2 Lower Ip to 0.8 MA, nl04 to 0.8e20. Raise Bt to 4.8 T. Starting 0.2 s after RF onset, ramp Bt down to 4.5 T and up to 4.8 T at a rate |dB/dt|~1 T/s. .Shots 3-4 Adjust Ip, Bt, nl04 as needed to obtain useful set of ECE cutoffs in H-mode. .Shots 5-6 (if necessary) Adjust GPC2 for 3.3 T operation (as configured for 1010614006). Run ohmic L-mode inner wall limited, 0.8 MA, nl04~1e20. Ramp Bt to 3.3 T and hold, then raise nl04 to 2e20. [If RF unavailable, go to Plan B: .Shots 1-4 Repeat 1000829027 (Ohmic EDA H-mode, 0.8 MA) with GPC2 adjusted for B_0=3.7 T. .Shots 5-6 same as above] | |
| Jun 20 2001 01:11:00:470PM | Martin Greenwald | Run plan: Density limit mechanisms - mp233a We want to collect more data on the changes in turbulence and transport which have been linked to the density limit. In the previous experiments it was observed that the regime of large coherent fluctuations which normally exists in the far scrape-off, moves inward to the separatrix and intrudes into the closed field line regions as the density limit is reached. We will try to insert the probe more deeply into these plasmas at high densities in order to follow the evolution of the profiles and fluctuations. In particular we will try to assess how far into the main plasma this phenomenon reaches. We will also use this opportunity to obtain more data on the changes in transport that accompany the change in fluctuations. The fast camera will be used to look for any visible changes in the edge turbulence - in particular to watch for progressive movement of the turbulent region as the density is raised. 1000620012 would be a good starting point. As before, the approach will be to produce high density ohmic discharges then to ramp down the plasma current to approach the density limit. This gives us density limit disruptions which are reproducible in time which eases the operation of the fast scanning probe. The B$_T$ programming might need to be altered to allow edge profile measurements until the time of the disruptions. Once the shot is set up, few changes are needed. | |
| Jun 20 2001 06:00:21:297PM | Martin Greenwald | Results: We made a good start, but this was only half a run and started later than we had planned. We got reproducible density limit disruptions and were able to push the probe in systematically. The probe was inserted at 0.95 sec and the disruptions occurred just after 1.0 sec. The cooling obviously proceeds in past the last closed flux surface. We see the break in profiles, turbulence, auto-correlation function in to about rho = -1 cm. Interesting analysis which should be done: a) plot breakpoint vs n/n_g b) calculate mhd equilibrium with current excluded from cold region c) analyze pci spectra d) look at shots with poloidal detachment near the density limit these seem to shrink in minor radius more or less to keep n/n_g ~ 1 If we get more time we will repeat the experiment with the probe plunge nearer to the density limit. Shots for further analysis: Shot A Probe position (nominal) 1010620014 - 4. mm 1010620016 - 5.7mm 1010620017 - 7.9mm 1010620019 -11. mm 1010620020 -14.2mm | |
| Jun 20 2001 09:09:41:007AM | 1010620001 | Jerry Hughes | Good shot, but got no Thomson data due to the port shutter being closed. RF decent, multiple H-modes. numerous cutoffs on GPC and GPC2. Repeat to get Thomson data. |
| Jun 20 2001 10:18:21:067AM | 1010620002 | Jerry Hughes | Shot 2: Good shot. Multiple H-modes, and over 20 GPC cutoff points. Can use to check Thomson channels D,G,L,B |
| Jun 20 2001 10:03:57:387AM | 1010620003 | Jerry Hughes | Shot 3: Injection occurred at .83 s, leading to disruption prior to reaching cutoff. Repeat with minor adjustment to Bt sweep. |
| Jun 20 2001 10:32:31:353AM | 1010620004 | Jerry Hughes | Shot 4: Shot went as programmed. 5 ELM-free H-modes. Density doesn't reach cutoff prior to H-L transition in any case. So we will try raising the target nl04 to 1e20. Perhaps this will make the H-mode more EDA-like, also. |
| Jun 20 2001 11:03:46:510AM | 1010620005 | Jerry Hughes | Shot 5: Shot ran well. Got 4 marginal EF/EDA H-modes. Good cutoff data, especially during the 3rd H-mode. On next shot, we will try to get more EDA-like H-modes by lowering Ip to 0.7 MA, while raising the target nl04 to 1.2e20. Cutoff data is better at lower field. We will try starting at 4.5 T and ramp UP to 4.8 T. |
| Jun 20 2001 11:30:53:350AM | 1010620006 | Jerry Hughes | Shot 6: killed by injections at 0.67--0.69 s. Target nl04, Ip, Bt looked good, however. |
| Jun 20 2001 11:56:46:543AM | 1010620007 | Jerry Hughes | Shot 7: killed by injections at 0.69 s. RF? Bob will back off the density, see if it helps. |
| Jun 20 2001 12:14:19:853PM | 1010620008 | Jerry Hughes | Shot 8: The injections continue. We will abandon RF and move on to the last part of the run plan, L-mode, inner-wall limited, with nlo4 ramp from 0.8--2.0e20. |
| Jun 20 2001 01:00:30:300PM | 1010620009 | Jerry Hughes | Shot 9 ran mostly as programmed. Cutoffs prevalent in both GPC and GPC2. Signals less clear at the edge than in the core, but I think we can use them. Will turn run over to Martin. |
| Jun 20 2001 01:22:03:677PM | 1010620010 | Martin Greenwald | First shot in density limit run reloaded shot 1000620012 disrupted right on schedule n/n_g = 0.88 |
| Jun 20 2001 01:55:11:760PM | 1010620011 | Martin Greenwald | disrupts early |
| Jun 20 2001 01:55:22:743PM | 1010620012 | Martin Greenwald | fizzle |
| Jun 20 2001 02:28:10:480PM | 1010620013 | Martin Greenwald | Good shot will start pushing probe in next |
| Jun 20 2001 03:04:12:677PM | 1010620014 | Martin Greenwald | Good shot probe in to ~ -4 mm |
| Jun 20 2001 03:04:53:550PM | 1010620015 | Martin Greenwald | early disruption |
| Jun 20 2001 03:41:46:530PM | 1010620016 | Martin Greenwald | Good Shot probe in about rho = -5.7 mm |
| Jun 20 2001 04:00:21:153PM | 1010620017 | Martin Greenwald | Good Shot probe in to rho = -7.9 mm |
| Jun 20 2001 04:08:15:010PM | 1010620018 | Martin Greenwald | Interferometer failed density feedback disturbed apparently no gas puff much lower density |
| Jun 20 2001 04:57:26:060PM | 1010620019 | Martin Greenwald | Good Shot probe to rho = - 11 mm |
| Jun 20 2001 05:18:42:170PM | 1010620020 | Martin Greenwald | Good Shot probe to -14.2mm |
| Physics Operator Comments | |||
| Jun 19 2001 06:12:10:533PM | Robert Granetz | Engineering setup: ECDC in D2 overnight prior to run. Be prepared for ECDC in D2 between shots using B-side-upper valve. (Z-meter/bolometer shutter should be closed during ECDC, opened for plasma.) Power systems as on 1001215023. Gas setup: fill B-top with 6 psi of D2 Hybrid enabled (PG4) fill B-side lower with 1 psi of Ar Hybrid enabled (PG1) fill B-side upper with 30 psi of D2 Hybrid DISABLED (PG2) fill C-side with 30 psi of D2 Hybrid enabled (PG3) fill J-bottom with 30 psi of He Hybrid DISABLED (PG5) Enable the following gate valves: ECE, DNB, VUV Run starts at 09:00 and ends at 17:00. ------------------------------------------------------------------------------- RF Setup: Transmitters 1 and 2 should be in run-on by 08:00. We will need 1-2 MW from D and E antennas for MP 296. No RF is needed for MP 233A. ------------------------------------------------------------------------------- Run Plan: MP 296 : Thomson calibration using ECE cutoff We will do this first. In order to promote ECE cutoff, run at 4.5 tesla and high density. Obtain high density by getting into H-mode (possibly with ITB's) with 1-2 MW from D and E antennas. Start from shot 1001215023. Btor, Ip, and ne ramping will probably also be tried. MP 233A: Density limit mechanisms Ramp down Ip to reach the density limit in ohmic plasmas. Expect lots of density-limit disruptions. Start from shot 1000620023. Fluctuation and edge diagnostics should have fast windows during the H-L transition and near the L-mode disruption if possible. | |
| Jun 20 2001 09:28:39:007AM | Robert Granetz | Overnight ECDC in D2 was done. Hybrid coldstart done; no errors found Loaded segments 2,3,4 from 1001215023, as per Jerry's instructions, but I changed density feedback to use the TCI instead of the Z-meter. I also zeroed the B-side-upper valve programming, since that's now for between-shot ECDC. DNB is not operating this morning. | |
| Jun 20 2001 09:07:29:800AM | 1010620001 | Robert Granetz | Shot 01 -- Plasma. Good shot. 1 MA, 4.5 T. Multiple H-modes. Prf=0.78 MW. The Thomson shutter unexpectedly closed, so we will have to repeat this shot. GPC cutoff several times. Next shot: add +5 amps to IC_EF4. No other changes (except have Thomson keep their shutter open). |
| Jun 20 2001 09:28:06:753AM | 1010620002 | Robert Granetz | Shot 02 -- Plasma. Good shot. 1 MA, 4.5 T. Multiple H-modes. Prf=1.0 MW (from E only). GPC had one cutoff period. Thomson data OK. Next shot: lower Ip to 0.8 MA, lower target density to nl_04=0.8e20 m-2, raise Btor to 4.8 T, but put in a ramp down to 4.5 T and then back up to 4.8 T, starting at t=0.8 s. Turn on between-shot ECDC. |
| Jun 20 2001 09:52:35:713AM | 1010620003 | Robert Granetz | Shot 03 -- Plasma. Disrupted at t=0.86 s due to a big injection at t=0.83 s. Btor ramped from 4.80 to 4.56 T and then back to 4.80 T. Target density was nl_04=0.8e20 m-2, as desired. Prf=1.2 MW, mostly from E. The D antenna system is not doing well. Next shot: repeat with faster Btor ramp. ECDC in D2 is going between shots. |
| Jun 20 2001 10:26:04:420AM | 1010620004 | Robert Granetz | Shot 04 -- Plasma. Good shot. Ip, Btor, and nl_04 are as requested. Multiple ELMfree H-modes. Prf=1.3 MW, mostly from E. GPC didn't show clear cutoffs. H/D=5-11%. Next shot: raise density to nl_04=1.0e20 m-2. ECDC in D2 is going between shots. |
| Jun 20 2001 10:54:30:717AM | 1010620005 | Robert Granetz | Shot 05 -- Plasma. Good shot. Got the higher target density. Multiple H-modes. Prf=1.5 MW. Jerry got good cutoff data. H/D=5-10%. Next shot: Lower Ip to 0.7 MA, raise target nl_04 to 1.2e20 m-2, lower Btor to 4.5 T, but include a ramp up to 4.8 T and back down to 4.5 T (with same timing as previous shots). ECDC in D2 is going between shots. |
| Jun 20 2001 11:32:04:460AM | 1010620006 | Robert Granetz | Shot 06 -- Plasma. Disrupted at t=0.69 s due to an impurity injection. Got the requested Ip, Btor, and nl_04. Next shot: try the same thing again. ECDC 2.45 GHz magnetron has failed. There will be no more ECDC during the run. |
| Jun 20 2001 12:35:31:230PM | 1010620008 | Robert Granetz | Shot 08 -- Plasma. Disrupted at t=0.83 s. Give up on this. Next shot: set Btor=3.3 T (92 kA), Ip=0.8 MA, nl_04 ramping from 0.8 to 2.0e20 m-2, inner wall limited (reduce RCUR by 1.0 cm and CLEARIN by 2.0 cm). Long delay due to CMODA computer crash. |
| Jun 20 2001 01:09:22:233PM | 1010620009 | Robert Granetz | Shot 09 -- Plasma. Good ohmic L-mode shot. Ip=0.76 MA, Btor=3.40 T, nl_04 ramped up to 1.5e20 m-2. GPC was solidly cutoff. Plasma was on the line between limited and diverted. End of MP 296: CMODA crashed again. Switch to MP 233A: Next shot: load shot 1000620012, an ohmic, diverted, high-density disruption shot. Set fast windows on Mirnov and x-rays. |
| Jun 20 2001 01:38:20:497PM | 1010620010 | Robert Granetz | Shot 10 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.04 s. Outer gap = 8 mm. Inner gap = 15 mm. Next shot: increase outer gap to 15 mm and inner gap to 20 mm. (reduce RCUR by 1 mm and increase CLEARIN by 5 mm) |
| Jun 20 2001 01:47:23:560PM | 1010620011 | Robert Granetz | Shot 11 -- Plasma. Disrupted at t=0.28 s, possibly because the CLEARIN change started too early in the shot. Next shot: undo change to CLEARIN for the early part of the shot. |
| Jun 20 2001 01:58:15:013PM | 1010620012 | Robert Granetz | Shot 12 -- Fizzle. Next shot: no changes |
| Jun 20 2001 02:26:30:587PM | 1010620013 | Robert Granetz | Shot 13 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Outer gap = 10-15 mm. Inner gap = 20 mm. Next shot: no changes |
| Jun 20 2001 02:55:11:867PM | 1010620014 | Robert Granetz | Shot 14 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Got good probe data. ASP sees blobby fluctuations well inside of the separatrix. Next shot: no PCS changes. Brian will send the ASP in farther. |
| Jun 20 2001 03:11:49:720PM | 1010620015 | Robert Granetz | Shot 15 -- Plasma. Disrupted early at t=0.30 s due to momentary excessive elongation and vertical instability. Next shot: reduce CLEARIN early in the shot again. Reduce pre-fill by 2 ms for post-disruption recovery. |
| Jun 20 2001 03:25:35:413PM | 1010620016 | Robert Granetz | Shot 16 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.02 s. Still showed signs of vertical instability around t=0.27 s. Good probe data. Next shot: add 2 ms back to the pre-fill puff. |
| Jun 20 2001 03:53:24:300PM | 1010620017 | Robert Granetz | Shot 17 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.01 s. Good probe data. Next shot: no changes |
| Jun 20 2001 04:16:29:607PM | 1010620018 | Robert Granetz | Shot 18 -- Plasma. TCI feedback failed. CO2 laser was off. No gas fueling --> low density --> late disruption, high edge temperatures --> nearly cooked the ASP. Next shot: no PCS changes Cell access for Jim Irby and Rick Murray to fix the TCI. |
| Jun 20 2001 04:43:27:210PM | 1010620019 | Robert Granetz | Shot 19 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.04 s. Good probe data. Next shot: no changes |
| Jun 20 2001 05:03:30:037PM | 1010620020 | Robert Granetz | Shot 20 -- Plasma. Good ohmic, diverted, density-limit disruption at t=1.02 s. Good probe data. End of run |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:56:57:533AM | Plasma | Ok | |
| 2 | 09:16:21:453AM | Plasma | Ok | |
| 3 | 09:39:52:490AM | Plasma | Ok | |
| 4 | 10:12:24:743AM | Plasma | Ok | |
| 5 | 10:37:57:377AM | Plasma | Ok | |
| 6 | 11:04:45:230AM | Plasma | Ok | |
| 7 | 11:39:27:177AM | Plasma | Ok | |
| 8 | 12:02:47:087PM | Plasma | Ok | |
| 9 | 12:41:30:800PM | Plasma | Ok | |
| 10 | 01:16:37:857PM | Plasma | Ok | |
| 11 | 01:39:33:453PM | Plasma | Ok | |
| 12 | 01:53:40:037PM | Plasma | Ok | |
| 13 | 02:16:15:977PM | Plasma | Ok | |
| 14 | 02:40:22:767PM | Plasma | Ok | |
| 15 | 03:03:29:770PM | Plasma | Ok | |
| 16 | 03:20:51:640PM | Plasma | Ok | |
| 17 | 03:41:57:047PM | Plasma | Ok | |
| 18 | 04:02:47:343PM | Plasma | Ok | |
| 19 | 04:39:06:687PM | Plasma | Ok | |
| 20 | 04:58:48:360PM | Plasma | Ok | |