| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Catherine Fiore,Martin Greenwald |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Bill Cochran,Gary Dekow |
| Engineering Operator Run Comment |
| MP 257 - ITB contol SL: Fiore, MP 275 ITB Formation by off-axis RF SL: G |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:24:600PM |
| Author: To Be Determined |
| #46 of 47 OPS Date: 30-JUN-2000 17:29 Expires: 14-JUL-2000 00:00 From: HAZARD::FIORE Subj: Run summary for 1000630a MP 257 -- ITB control ------------------------------------------------------------------------------- We are trying to get the HIREX ion temperature profiles during the ITB/EN mode, which we were unable to do on the June 15th run because of CAMAC problems. The goal is to get 3 or 4 reproducible shots with a 20 ms timing window on HIREX to catch the ion temperature peak. First, set up a reliable H-mode plasma at 5.3 T, 1 MA, 1.5 to 2 MW rf power, nl_1=1e20. Program rf to drop to .5 MW for 100 ms, then return to the orgiginal value for the duration. The timing of the HIREX data collection window should be set to coordinate with the point that the rf power is cut, so that a pre and post transition ion temperature profile could be obtained. Repeat for as many shots as is needed by John Rice. ---------------------------------------------------------------------------- Shot 1 Good shot. Two nice ITB/EN's, although not timed to the drop in RF power. The RF power was a little low and the plasma had trouble staying in H-mode. HIREX had a problem, so we will repeat this shot. Shot 2-- No plasma. Shot 3--Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX data is good. We will repeat this for several more shots. Shot 4--Good shot. Three nice ITB/EN's, two spontaneous, one at the rf power drop. HREX data is good for 3 chords. We will repeat this for several more shots. Shot 5--Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX only has one channel working. We will repeat this for several more shots. Shot 6--Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX had three channels working. We need one or two more shots. Shot 7--Good shot. Three nice ITB/EN's, two spontaneous, one at the rf power drop. HREX had three channels working. We are turning over the run to Martin. |
| Entered: Jul 7 2004 03:49:24:617PM |
| Author: To Be Determined |
| Run Summary for 1000630 MP 275 ITB Formation and RF Flow Drive Session Leader - Greenwald Phys Op - Granetz Background: Edge and core barriers are generally believed to be due to suppression of ion turbulence by sheared ExB flows. Bifurcation can occur because of positive feedback between the pressure gradient, E$_r$, and sheared flow suppression. Since the diamagnetic contribution to E$_r$ is negative, rotation in the counter-current direction can enhance the effect and co-current rotation can inhibit it . In C-Mod, we have consistently measured co-rotation which is particularly strong in RF heated H-modes (but which is present in RF heated L-mode and in ohmic H-modes as well.). We have speculated that the existence of this ``natural" co-rotation may prevent the formation of ITB's in many circumstances. Further, if the rotation could be reduced or reversed, barriers might form much more readily. In fact, recent theories suggest that the flow could be reversed by moving the ICRF resonance to the high-field side (inboard) of the plasma. Recent experiments (see 1000523 and 1000607) to test this theory did show formation of density transport barriers and an apparent reduction/reversal of the toroidal flow. It is not clear however, if these results are related to the speculations discussed above. Regardless of the origin of the flow reduction/reversal, to test our hypothesis we would like to measure time dependent profiles of T$_i$, V$_\phi$, and V$_\theta$. This would allow us to calculate the shearing rate $\omega_{ExB}(r)$ which is the term which is believed to stabilize turbulence. (Radial dependences are important since it is the gradient in E$_r$ which is important. The contributions from co-current rotation and the pressure gradient may or may not cancel depending on their profiles - offset gradients could lead to very high shearing rates.) This can then be compared to calculations of the linear growth rate $\gamma_L(r)$ from the gs2 code. To confirm our hypothesis, changes in $\omega_{ExB}(r)$ should lead changes in the density profile and should approach qualitatively $\gamma_L(r)$. The physics of the barrier location is also of interest since for these shots q$_0 \le$ 1. Most experiments with ITBs are for q$_0 \ge$ 1, with very weak or reversed shear. Plan: Duplicate 1000607007. More or less a normal shot with Bt = 4.5T. Scan Hirex to get temperature and rotation profiles, time histories. Results: We had a Reasonable number of good shots. There was lots of radiation - Twhen it reaches Pinput the shot reverts to L-mode. The result is that there are many L/H/L transitions during each shot. The toroidal rotation consistently reverses with strong density peaking. The maximum effect was seen during L-mode phases. On several shots, strong mhd (m=1) was seen as the density peaked. Typically the sawteeth ended before the onset of the MHD. (see shots 14,17,21,23) At the end of the run we ran limited shots (025, 026) to see if these effects would persist in an all L-mode plasma. No peaking or flow reversal was observed. The J port antenna (2 inner straps) was run and contributed up to 1.5 MW. No serious impurity problems were found. On shot 26, we had close to 5 MW of RF power. The last shot of the day (027) was run at 5.3 T. Even with total power near 5 MW, no transition was seen in this limited discharge. This should provide a good data point for MP 262. Shots for further analysis of Ti and Vphi profiles w/ full power, full length 1000630009 1000630010 1000630012 1000630014 1000630017 1000630020 1000630021 1000630023 |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:11:583PM |
| Author: To Be Determined |
| Physics operator summary for run 1000630: MP 257 -- ITB control (EN modes) Session leader: C. Fiore MP 275 -- ITB formation by off-axis RF Session leader: M. Greenwald Physics operator: R. Granetz Engineering operators: G. Dekow/B. Cochran Summary: The machine ran very well today. The first MP was completed, and much progress was made on the second MP. Off-axis heating tended to produce disruptions, usually late in the shot. The last three shots were inner-wall limited, and showed no signs of a core barrier. The last shot had 3-4.5 MW of on-axis ICRF, but no H-modes. There were no power supply problems, nor computer problems. HIREX was working well enough to get the necessary Ti and rotation data. Scorecard: 23 plasmas 4 fizzles 0 duds 0 tests 0 aborted ---------- 27 total ------------------------------------------------------------------------------- Engineering setup for Friday, 30 June 2000: Overnight ECDC in D2, stopping 1-2 hours prior to the run. Run begins at 9:00 and ends at 17:00. Power system setup as on 1000523008. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid enabled leave B-side upper as is Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming no vacuum problems: ECE, VUV DNB gate valve should be DISABLED at the start of the run. RF setup: D and E, pulse at 0.6s, 2 MW, drop to 0.5 MW at 1 s for 100 ms, increase back up to 1.5 or 2 MW at 1.1 s. ------------------------------------------------------------------------------- Run plan: We will attempt to finish up 2 MP's, now that John Rice has gotten 4 out of 5 Hirex chords working again. MP 257 -- ITB control (EN modes) Session leader: C. Fiore MP 275 -- ITB formation by off-axis RF Session leader: M. Greenwald We'll start with Catherine's MP, loading from shot 1000523008 (1 MA, 5.3 T). We'd like RF on the first plasma, programmed as specified above. After we get a good Ti profile (maybe on 4 shots), we'll switch to Martin's MP, loading from shot 1000607007 (0.8 MA, 4.5 T). For Catherine's MP, the timing of the HIREX data collection window should be set to coordinate with the point that the rf power is cut, so that a pre and post transition ion temperature profile could be obtained. ------------------------------------------------------------------------------- Overnight ECDC in D2 was done, stopping 2 hours prior to the run Hybrid coldstart done; no errors found Loaded segment 1 from 1000629024 (last shot from yesterday). Loaded segment 2 from 1000523008, then loaded CLEARIN from shot 1000629017 and adjusted, in order to get the new offset. Loaded segment 3 from 1000607007, and again loaded CLEARIN from 1000629017 and adjusted. Loaded segment 4 from 1000526022, and again loaded CLEARIN from 1000629017 and adjusted. ------------------------------------------------------------------------------- Shot 01 -- Plasma. Good shot. 1.0 MA, 5.3 T, nl_04=1.0e20 m-2, full length. Got two good EN modes, but not at the desired time. There was a problem with HIREX. Prf=1 MW only. Next shot: repeat. Hopefully John will get HIREX working. We're pausing here to give John Rice access to the HIREX crates in the cell. Shot 02 -- Fizzle. Null and pressure look fine. Next shot: add 10 amps to IC_EF4 Shot 03 -- Plasma. Good shot. This one also has two EN modes, one of which is at t=1.04 s (in the desired time window). Prf=2 MW. John has four HIREX chords working. Next shot: repeat, no changes. Shot 04 -- Plasma. Good shot. Three EN modes, one in the desired window. Only three HIREX chords working on this shot. Next shot: Tweak Br0, otherwise repeat. (We need 4 identical shots to get a Ti profile.) Shot 05 -- Plasma. Good shot. Two EN modes, one in the desired window. Only one HIREX chord worked. Prf=2 MW. Both D and E are "happy as a clam" (Rejean's words). John went into the cell to work on HIREX. Next shot: repeat, no changes. Shot 06 -- Plasma. Good shot. Two EN modes. Three HIREX chords worked. Prf=2 MW. Next shot: repeat, no changes, except that J3 will be turned on near the end of the pulse. On second thought, make a Br0 tweak. Shot 07 -- Plasma. Good shot. Three EN modes. Three HIREX chords worked. Prf=2-3 MW, including J3 during the latter portion of the flattop. End of MP #257. Start of MP #275. Next shot: switch to segment 3 instead of segment 2. This should be an 0.8 MA, 4.5 T shot. Make another Br0 tweak. It's really jumping around from shot-to-shot. John Rice needed another cell entry. Shot 08 -- Plasma. Disrupted at t=0.95 s. JR reports that a big molybdenum injection was the cause. Ip=0.8 MA, Btor=4.5 T. Next shot: no changes Shot 09 -- Plasma. Disrupted at t=1.18 s. Pwf=2.8 MW. Multiple H-modes. Elongation is 1.68. Inner gap=19-20 mm. Outer gap=15 mm. Next shot: reduce elongation by reducing CLEARIN by 4 mm, but keep outer gap the same by also reducing RCUR by 2 mm. Shot 10 -- Plasma. Good shot. Lots of H-modes and injections. The elongation and the inner gap didn't change due to my physop error: I made the changes in segment 2, but we're using segment 3 for this part of the run. Next shot: reduce elongation (in segment 3) by reducing CLEARIN by 3 mm, but keep outer gap the same by also reducing RCUR by 1.5 mm. Shot 11 -- Plasma. Good shot. Lots of little H-modes. The elongation did reduce, without changing the outer gap. Next shot: repeat, no changes. Shot 12 -- Plasma. Disrupted at t=1.13 s. Lots of Prad. Next shot: repeat, no changes. Rick Murray had to go into the cell for the TCI Shot 13 -- Plasma. Good shot. Disrupted at t=1.60 s (during rampdown). E-port faulted. Prf=1.4 MW. Next shot: repeat, no changes. Shot 14 -- Plasma. Good shot. Lots of little H-modes. Prf=2.8 MW. Huge MHD oscillations from t=1.01-1.11 s. Next shot: repeat, no changes. Shot 15 -- Fizzle. Null and pressure look fine. Next shot: tweak Br0. Shot 16 -- Plasma. Good shot. Disrupted at t=1.60 s (during rampdown). Lots of little H-modes. E-port faulted, Prf=1.4 MW. Next shot: repeat, no changes Shot 17 -- Plasma. Disrupted at 1.52 s, just into rampdown. Prf=2.8 MW. Large m=1 around t=1.3 s. Next shot: reduce outer gap from 16 to 13 mm (increase RCUR by 1.5 mm) at the request of the RF Shot 18 -- Plasma. Good shot. Lots of little H-modes. Prf=2.8 MW. Something tried to take a chunk out of the current at t=1.37 s. Next shot: repeat, no changes. Shot 19 -- Fizzle. Next shot: subtract 10 amps from IC_EF4, and reduce argon puff from 50 to 40 ms. Shot 20 -- Plasma. Disrupted at t=1.32 s. Lots of little H-modes. Prf=2.8 MW Next shot: repeat, no changes Shot 21 -- Plasma. Good shot. No disruption. Prf=2.8 MW. Large m=1 around t=1 s. Next shot: repeat, no changes Shot 22 -- Fizzle. Bz is a touch higher than the previous shots. Next shot: subtract another 10 amps from IC_EF4. Shot 23 -- Plasma. Good shot. Disrupted during rampdown. Prf=2.8 MW. The startup almost died. Lots of little H-modes. Next shot: change configuration to a limited plasma, without changing the outer gap. Also add 5 amps back to IC_EF4. Shot 24 -- Plasma. Disrupted at t=1.14 s. I made a physop mistake with the direction of the RCUR change, and the plasma ended up being limited on the outboard side instead of the inboard side. Next shot: this time, reduce RCUR by 9 mm from what it was on shot 22. Shot 25 -- Plasma. Good shot. Inner wall limited. No disruption. No H-modes. Magnetics Traq_1 data corrupted. EFIT rerun with hybrid input data. Prf=2.8-2.9 MW, with a brief pulse of J3 bringing it up to 4 MW. Outer gap is around 20 mm instead of 15 mm, but the RF coupled very well, so we'll leave it this way. Next shot: repeat, no changes Shot 26 -- Plasma. Good shot. Inner wall limited. Full length. Lots of hard x-rays. Startup almost didn't make it. Prf=4.0-5.0 MW ! No H-modes. Next shot: raise Btor to 5.3 tesla. Add 5 more amps to IC_EF4. Shot 27 -- Plasma. Good shot. Inner wall limited. Btor=5.3 T. Prf=3.2-4.4 MW No H-modes, even though the heating is on-axis. End of run. |
| Session Leader Comments | |||
| Jun 30 2000 08:33:57:983AM | Catherine Fiore | P 257 -- ITB control ------------------------------------------------------------------------------- We are trying to get the HIREX ion temperature profiles during the ITB/EN mode, which we were unable to do on the June 15th run because of CAMAC problems. The goal is to get 3 or 4 reproducible shots with a 20 ms timing window on HIREX to catch the ion temperature peak. First, set up a reliable H-mode plasma at 5.3 T, 1 MA, 1.5 to 2 MW rf power, nl_1=1e20. Program rf to drop to .5 MW for 100 ms, then return to the orgiginal value for the duration. The timing of the HIREX data collection window should be set to coordinate with the point that the rf power is cut, so that a pre and post transition ion temperature profile could be obtained. Repeat for as many shots as is needed by John Rice. ------------------------------ | |
| Jun 30 2000 11:13:56:327AM | Martin Greenwald | Starting with shot 8 we will be doing MP 275 ITB Formation and RF Flow Drive Background: Edge and core barriers are generally believed to be due to suppression of ion turbulence by sheared ExB flows[1]. Bifurcation can occur because of positive feedback between the pressure gradient, E$_r$, and sheared flow suppression. Since the diamagnetic contribution to E$_r$ is negative, rotation in the counter-current direction can enhance the effect and co-current rotation can inhibit it [2]. In C-Mod, we have consistently measured co-rotation which is particularly strong in RF heated H-modes (but which is present in RF heated L-mode and in ohmic H-modes as well.[3]). We have speculated that the existence of this ``natural" co-rotation may prevent the formation of ITB's in many circumstances. Further, if the rotation could be reduced or reversed, barriers might form much more readily. In fact, recent theories [4] suggest that the flow could be reversed by moving the ICRF resonance to the high-field side (inboard) of the plasma. Recent experiments (see 1000523 and 1000607) to test this theory did show formation of density transport barriers and an apparent reduction/reversal of the toroidal flow. It is not clear however, if these results are related to the speculations discussed above. Regardless of the origin of the flow reduction/reversal, to test our hypothesis we would like to measure time dependent profiles of T$_i$, V$_\phi$, and V$_\theta$. This would allow us to calculate the shearing rate $\omega_{ExB}(r)$ which is the term which is believed to stabilize turbulence. (Radial dependences are important since it is the gradient in E$_r$ which is important. The contributions from co-current rotation and the pressure gradient may or may not cancel depending on their profiles - offset gradients could lead to very high shearing rates.) This can then be compared to calculations of the linear growth rate $\gamma_L(r)$ from the gs2 code[5]. To confirm our hypothesis, changes in $\omega_{ExB}(r)$ should lead changes in the density profile and should approach qualitatively $\gamma_L(r)$. The physics of the barrier location is also of interest since for these shots q$_0 \le$ 1. Most experiments with ITBs are for q$_0 \ge$ 1, with very weak or reversed shear. Plan: Duplicate 1000607007. Scan Hirex to get temperature and rotation profiles, time histories. 10 shots | |
| Jun 30 2000 09:07:18:030AM | 1000630001 | Catherine Fiore | Good shot. Two nice ITB/EN's, although not timed to the drop in RF power. The RF power was a little low and the plasma had trouble staying in H-mode. HIREX had a problem, so we will repeat this shot. |
| Jun 30 2000 09:38:56:483AM | 1000630003 | Catherine Fiore | Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX data is good. We will repeat fhis for several more shots. |
| Jun 30 2000 09:59:02:780AM | 1000630004 | Catherine Fiore | Good shot. Three nice ITB/EN's, two spontaneous, one at the rf power drop. HREX data is good. We will repeat fhis for several more shots. |
| Jun 30 2000 10:21:37:577AM | 1000630005 | Catherine Fiore | Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX only has one channel working. We will repeat fhis for several more shots. |
| Jun 30 2000 10:41:30:090AM | 1000630006 | Catherine Fiore | Good shot. Two nice ITB/EN's, one spontaneous, one at the rf power drop. HREX had three channels working. We need one or two more shots. |
| Jun 30 2000 11:04:25:903AM | 1000630007 | Catherine Fiore | Good shot. Three nice ITB/EN's, two spontaneous, one at the rf power drop. HREX had three channels working. We are turning over the run to Martin. |
| Jun 30 2000 11:28:31:420AM | 1000630008 | Martin Greenwald | Disrupted early - 0.95 sec moly injection |
| Jun 30 2000 11:48:50:530AM | 1000630009 | Martin Greenwald | good shot density peaking and flow reversal in evidence |
| Jun 30 2000 12:06:23:687PM | 1000630010 | Martin Greenwald | Similar shot, but doesn't disrupt density peaking ne0/nebar ~ 1.6 |
| Jun 30 2000 12:26:05:467PM | 1000630011 | Martin Greenwald | D antenna tripped flow reversal seen, but weak density peaking |
| Jun 30 2000 12:48:01:357PM | 1000630012 | Martin Greenwald | disrupts at 1.1 seconds quite peaked before disruption 1.7-1.8 toroidal flow down to 0 |
| Jun 30 2000 01:12:09:340PM | 1000630013 | Martin Greenwald | similar to last shot E antenna trips early only weak peaking |
| Jun 30 2000 01:22:25:623PM | 1000630014 | Martin Greenwald | Good shot Lots of RF power and no disruption v. strong peaking ending a bit after some strong MHD at 1.1 seconds MHD shows up on many diagnostics Recovers later with even stronger peaking and flow reversal |
| Jun 30 2000 01:34:12:390PM | 1000630015 | Martin Greenwald | fizzle |
| Jun 30 2000 02:07:43:373PM | 1000630017 | Martin Greenwald | RF (E) trips - only 1.5 MW for most of the shot many h-modes peaks during L-mode phase |
| Jun 30 2000 02:16:24:200PM | 1000630017 | Martin Greenwald | Good shot very strong density peaking ~ 2. mhd at around 1.3 sec |
| Jun 30 2000 02:36:22:827PM | 1000630018 | Martin Greenwald | Only OK weak peaking until very end |
| Jun 30 2000 02:44:23:750PM | 1000630019 | Martin Greenwald | fizzle |
| Jun 30 2000 03:10:40:403PM | 1000630020 | Martin Greenwald | Good Shot But peaking is heavily modulated by L/H transition |
| Jun 30 2000 03:28:01:640PM | 1000630021 | Martin Greenwald | Good shot Ragged H-modes strong MHD at 1 sec |
| Jun 30 2000 03:39:15:500PM | 1000630022 | Martin Greenwald | fizzle |
| Jun 30 2000 03:58:15:420PM | 1000630023 | Martin Greenwald | Good Shot good peaking More MHD |
| Jun 30 2000 04:14:42:000PM | 1000630024 | Martin Greenwald | First try at limit shot disrupts early almost no RF power |
| Jun 30 2000 04:42:48:530PM | 1000630025 | Martin Greenwald | Limited - L-mode throughout good RF power no sign of density peaking some power from J3 - Total RF up to 4 MW briefly Problem with magnetics - EFIT ran on PCS data |
| Jun 30 2000 05:06:26:357PM | 1000630026 | Martin Greenwald | Good shot no peaking Lots of RF power - reaches 5MW |
| Jun 30 2000 05:17:20:857PM | 1000630027 | Martin Greenwald | Went to 5.3 T for on axis heating RF power not quite as high No H-mode even with more than 4 MW |
| Physics Operator Comments | |||
| Jun 30 2000 08:25:51:500AM | Robert Granetz | Engineering setup for Friday, 30 June 2000: Overnight ECDC in D2, stopping 1-2 hours prior to the run. Run begins at 9:00 and ends at 17:00. Power system setup as on 1000523008. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid enabled leave B-side upper as is Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming no vacuum problems: ECE, VUV DNB gate valve should be DISABLED at the start of the run. RF setup: D and E, pulse at 0.6s, 2 MW, drop to 0.5 MW at 1 s for 100 ms, increase back up to 1.5 or 2 MW at 1.1 s. | |
| Jun 30 2000 08:26:18:280AM | Robert Granetz | Run plan: We will attempt to finish up 2 MP's, now that John Rice has gotten 4 out of 5 Hirex chords working again. MP 257 -- ITB control (EN modes) Session leader: C. Fiore MP 275 -- ITB formation by off-axis RF Session leader: M. Greenwald We'll start with Catherine's MP, loading from shot 1000523008 (1 MA, 5.3 T). We'd like RF on the first plasma, programmed as specified above. After we get a good Ti profile (maybe on 4 shots), we'll switch to Martin's MP, loading from shot 1000607007 (0.8 MA, 4.5 T). For Catherine's MP, the timing of the HIREX data collection window should be set to coordinate with the point that the rf power is cut, so that a pre and post transition ion temperature profile could be obtained. | |
| Jun 30 2000 08:42:27:890AM | Robert Granetz | Overnight ECDC in D2 was done, stopping 2 hours prior to the run Hybrid coldstart done; no errors found Loaded segment 1 from 1000629024 (last shot from yesterday). Loaded segment 2 from 1000523008, then loaded CLEARIN from shot 1000629017 and adjusted, in order to get the new offset. Loaded segment 3 from 1000607007, and again loaded CLEARIN from 1000629017 and adjusted. Loaded segment 4 from 1000526022, and again loaded CLEARIN from 1000629017 and adjusted. | |
| Jun 30 2000 09:05:56:560AM | 1000630001 | Robert Granetz | Shot 01 -- Plasma. Good shot. 1.0 MA, 5.3 T, nl_04=1.0e20 m-2, full length. Got two good EN modes, but not at the desired time. There was a problem with HIREX. Prf=1 MW only. Next shot: repeat. Hopefully John will get HIREX working. We're pausing here to give John Rice access to the HIREX crates in the cell. |
| Jun 30 2000 09:25:34:390AM | 1000630002 | Robert Granetz | Shot 02 -- Fizzle. Null and pressure look fine. Next shot: add 10 amps to IC_EF4 |
| Jun 30 2000 09:38:42:873AM | 1000630003 | Robert Granetz | Shot 03 -- Plasma. Good shot. This one also has two EN modes, one of which is at t=1.04 s (in the desired time window). Prf=2 MW. John has four HIREX chords working. Next shot: repeat, no changes. |
| Jun 30 2000 10:08:38:483AM | 1000630004 | Robert Granetz | Shot 04 -- Plasma. Good shot. Three EN modes, one in the desired window. Only three HIREX chords working on this shot. Next shot: Tweak Br0, otherwise repeat. (We need 4 identical shots to get a Ti profile.) |
| Jun 30 2000 10:27:34:560AM | 1000630005 | Robert Granetz | Shot 05 -- Plasma. Good shot. Two EN modes, one in the desired window. Only one HIREX chord worked. Prf=2 MW. Both D and E are "happy as a clam" (Rejean's words). John went into the cell to work on HIREX. Next shot: repeat, no changes. |
| Jun 30 2000 10:53:48:920AM | 1000630006 | Robert Granetz | Shot 06 -- Plasma. Good shot. Two EN modes. Three HIREX chords worked. Prf=2 MW. Next shot: repeat, no changes, except that J3 will be turned on near the end of the pulse. On second thought, make a Br0 tweak. |
| Jun 30 2000 11:06:50:500AM | 1000630007 | Robert Granetz | Shot 07 -- Plasma. Good shot. Three EN modes. Three HIREX chords worked. Prf=2-3 MW, including J3 during the latter portion of the flattop. End of MP #257. Start of MP #275. Next shot: switch to segment 3 instead of segment 2. This should be an 0.8 MA, 4.5 T shot. Make another Br0 tweak. It's really jumping around from shot-to-shot. John Rice needed another cell entry. |
| Jun 30 2000 11:36:37:263AM | 1000630008 | Robert Granetz | Shot 08 -- Plasma. Disrupted at t=0.95 s. JR reports that a big molybdenum injection was the cause. Ip=0.8 MA, Btor=4.5 T. Next shot: no changes |
| Jun 30 2000 11:52:10:000AM | 1000630009 | Robert Granetz | Shot 09 -- Plasma. Disrupted at t=1.18 s. Pwf=2.8 MW. Multiple H-modes. Elongation is 1.68. Inner gap=19-20 mm. Outer gap=15 mm. Next shot: reduce elongation by reducing CLEARIN by 4 mm, but keep outer gap the same by also reducing RCUR by 2 mm. |
| Jun 30 2000 12:11:00:420PM | 1000630010 | Robert Granetz | Shot 10 -- Plasma. Good shot. Lots of H-modes and injections. The elongation and the inner gap didn't change due to my physop error: I made the changes in segment 2, but we're using segment 3 for this part of the run. Next shot: reduce elongation (in segment 3) by reducing CLEARIN by 3 mm, but keep outer gap the same by also reducing RCUR by 1.5 mm. |
| Jun 30 2000 12:27:26:310PM | 1000630011 | Robert Granetz | Shot 11 -- Plasma. Good shot. Lots of little H-modes. The elongation did reduce, without changing the outer gap. Next shot: repeat, no changes. |
| Jun 30 2000 12:48:59:013PM | 1000630012 | Robert Granetz | Shot 12 -- Plasma. Disrupted at t=1.13 s. Lots of Prad. Next shot: repeat, no changes. Rick Murray had to go into the cell for the TCI |
| Jun 30 2000 12:59:05:293PM | 1000630013 | Robert Granetz | Shot 13 -- Plasma. Good shot. Disrupted at t=1.60 s (during rampdown). E-port faulted. Prf=1.4 MW. Next shot: repeat, no changes. |
| Jun 30 2000 01:22:34:467PM | 1000630014 | Robert Granetz | Shot 14 -- Plasma. Good shot. Lots of little H-modes. Prf=2.8 MW. Huge MHD oscillations from t=1.01-1.11 s. Next shot: repeat, no changes. |
| Jun 30 2000 01:37:11:327PM | 1000630015 | Robert Granetz | Shot 15 -- Fizzle. Null and pressure look fine. Next shot: tweak Br0. |
| Jun 30 2000 01:52:50:857PM | 1000630016 | Robert Granetz | Shot 16 -- Plasma. Good shot. Disrupted at t=1.60 s (during rampdown). Lots of little H-modes. E-port faulted, Prf=1.4 MW. Next shot: repeat, no changes |
| Jun 30 2000 02:17:52:467PM | 1000630017 | Robert Granetz | Shot 17 -- Plasma. Disrupted at 1.52 s, just into rampdown. Prf=2.8 MW. Large m=1 around t=1.3 s. Next shot: reduce outer gap from 16 to 13 mm (increase RCUR by 1.5 mm) at the request of the RF |
| Jun 30 2000 02:34:00:000PM | 1000630018 | Robert Granetz | Shot 18 -- Plasma. Good shot. Lots of little H-modes. Prf=2.8 MW. Something tried to take a chunk out of the current at t=1.37 s. Next shot: repeat, no changes. |
| Jun 30 2000 03:01:33:890PM | 1000630019 | Robert Granetz | Shot 19 -- Fizzle. Next shot: subtract 10 amps from IC_EF4, and reduce argon puff from 50 to 40 ms. |
| Jun 30 2000 03:28:31:513PM | 1000630021 | Robert Granetz | Shot 21 -- Plasma. Good shot. No disruption. Prf=2.8 MW. Large m=1 around t=1 s. Next shot: repeat, no changes |
| Jun 30 2000 03:44:41:340PM | 1000630022 | Robert Granetz | Shot 22 -- Fizzle. Bz is a touch higher than the previous shots. Next shot: subtract another 10 amps from IC_EF4. |
| Jun 30 2000 04:01:51:873PM | 1000630023 | Robert Granetz | Shot 23 -- Plasma. Good shot. Disrupted during rampdown. Prf=2.8 MW. The startup almost died. Lots of little H-modes. Next shot: change configuration to a limited plasma, without changing the outer gap. Also add 5 amps back to IC_EF4. |
| Jun 30 2000 04:43:54:937PM | 1000630025 | Robert Granetz | Shot 25 -- Plasma. Good shot. Inner wall limited. No disruption. No H-modes. Magnetics Traq_1 data corrupted. EFIT rerun with hybrid input data. Prf=2.8-2.9 MW, with a brief pulse of J3 bringing it up to 4 MW. Outer gap is around 20 mm instead of 15 mm, but the RF coupled very well, so we'll leave it this way. Next shot: repeat, no changes |
| Jun 30 2000 04:57:36:560PM | 1000630026 | Robert Granetz | Shot 26 -- Plasma. Good shot. Inner wall limited. Full length. Lots of hard x-rays. Startup almost didn't make it. Prf=4.0-5.0 MW ! Next shot: raise Btor to 5.3 tesla. Add 5 more amps to IC_EF4. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:56:28:623AM | Plasma | Ok | |
| 2 | 09:13:50:030AM | Plasma | Ok | |
| 3 | 09:31:35:903AM | Plasma | Ok | |
| 4 | 09:54:03:717AM | Plasma | Ok | |
| 5 | 10:15:08:857AM | Plasma | Ok | |
| 6 | 10:35:23:950AM | Plasma | Ok | |
| 7 | 10:56:38:500AM | Plasma | Ok | |
| 8 | 11:21:48:577AM | Plasma | Ok | |
| 9 | 11:41:03:513AM | Plasma | Ok | |
| 10 | 11:57:33:107AM | Plasma | Ok | |
| 11 | 12:16:51:390PM | Plasma | Ok | |
| 12 | 12:36:52:780PM | Plasma | Ok | |
| 13 | 12:53:49:857PM | Plasma | Ok | |
| 14 | 01:11:43:700PM | Plasma | Ok | |
| 15 | 01:30:01:687PM | Plasma | Ok | |
| 16 | 01:47:01:560PM | Plasma | Ok | |
| 17 | 02:06:42:763PM | Plasma | Ok | |
| 18 | 02:24:13:543PM | Plasma | Ok | |
| 19 | 02:42:51:233PM | Plasma | Ok | |
| 20 | 02:59:02:327PM | Plasma | Ok | |
| 21 | 03:15:27:827PM | Plasma | Ok | |
| 22 | 03:36:23:780PM | Plasma | Ok | |
| 23 | 03:50:17:983PM | Plasma | Ok | |
| 24 | 04:10:36:793PM | Plasma | Ok | |
| 25 | 04:28:02:590PM | Plasma | Ok | |
| 26 | 04:46:12:107PM | Plasma | Ok | |
| 27 | 05:03:07:217PM | Plasma | Ok | |