Miniproposals

Miniproposal: Date Filed: Title: First Author: Session Leader: Alan Lynn (shots 1-33)

Engineering Operator Run Comment

Boronization Recovery/MP310/MP309; SL: Lynn; PO: Parker; EO: Cochran/Byf

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:30:193PM

Author: To Be Determined

Run Summary for 1020829 Boronization recovery and MP 309/310 Results: The boronization recovery was difficult and took the entire day, so no progress was made on either MP. These two MP's will be pushed back to tomorrow's run. We will start with MP 310, which is an ohmic run which needs a density scan (~8-10 shots) and small Bt ramps. Then we will switch to MP 309 which is a 5.4 T ITB run with (again) small Bt ramps. This MP is a continuation of the run on 1020820.

Physics Operator Summaries

Entered: Jul 7 2004 04:37:15:990PM

Author: To Be Determined

Engineering Setup for Thursday, August 29,2002 Recovery from Boronization MP 310 Te Thermal Transport with Perturbative Techniques MP 309 (Provisional) 5.4 T ITB Thermal Transport Investigation SL: Lynn PO: Parker Overnight Boronization One hour of ECDC in D2 before run, 6-7 AM Run Begins at 09:00 and ends at 17:00 Power systems setup the same as for Shot 1020814007 Gas setup: B-Top 6 psi D2 Hybrid Enabled (PG4) B-side lower 1 psi Ar Hybrid Enabled (PG1) B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC) C-Side 30 psi D2 Hybrid Enabled (PG3) J-Bottom leave as is, Hybrid DISABLED Enable the following gate valves, assuming no vacuum problems: ECE, VUV, DNB RF Setup: Transmitters 1,2,3,4 in Run On by 07:00 RUN PLAN: First shots will aim at recovering from boronization, followed by a fudicial shot, identical to 1020828007, in order to assess the effect of boronization. Then we'll begin with shots required to carry out the two miniproposals. For MP 310, the shots will be without RF. We anticipate about 8-10 shots, corresponding to two shots at each of four densities (0.3, 0.5, 0.7, 2.0x10^20) During these shots BT will be varied by ~0.07 T over 40 ms at three times, 1., 1.08 and 1.16 s (similar to shot 1020820024). The field perturbation will be from the nominal value of 5.4 T and the current will be 800 kA. Then for MP 309 we will attempt to form density ITB's with the RF (D&E on axis, J off axis). If successful, we'll again insert small field ramps into an ITB discharge at various times, e.g., 0.5, 1., 1.1 and 1.2 s. Again, the nominal field wil be 5.4 T and the current will be 800 kA. Run Summary As expected the recovery from boronization proved difficult and occupied th entire run. It was decided therefore to postpone the miniproposals 310 and 309 until Friday, Aug 30, 2002. The first 4 shots were duds. One problem was the calibration of the pressure gauge, which is now apparently reading nearly a factor of 2 too low. Also, the machine had been discharged cleaned in He, instead of D2 as had been requested. After the fourth dud, Steve Wolfe suggested discharge cleaning for 30 minutes in D2. This was a good suggestion, as shot 5 broke down, although it fizzled. But this allowed tuning the startup and finally, after two more fizzles, a nor- mal plasma was produced on shot 8. For the rest of the run, shots were routinely produced with about 50-50 probability of fizzling. A characteristic problem was indication of periodic bouncing as indicated by the H-alpha light. Attempts to mitigate this by adjusting the Bz stray field or by slowing the current rise by raising the fill pressure to slow the current rise were unsuccessful. During the run, the RF antennas were also being conditioned. It could be that impurities generated from the RF conditioning had an effect on subsequent shot startup. In any event, as mentioned, startup was only about 50% reliable. Fortunately, with the more rapid cooling the number of good shots during a run such as this one still permits a reasonable amount of data to be taken. An encouraging note is that reasonable H-modes were obtained with 1.5-1.7 MW power from the D&E antennas. Scorecard: 4 duds, 15 fizzles, 13 OK shots (1 disruption) and 1 no power shot.

Session Leader Comments
Aug 29 2002 05:08:23:140PM	1020829033	Alan Lynn	The entire day was spent doing boronization recovery. So no progress was made on either MP#309 or #310. These MP's will be run tomorrow, starting with 310 then proceeding with 309.

Physics Operator Comments
Aug 29 2002 09:12:59:020AM	1020829001	Ron Parker	Shot 1 was a dud. We are recovering from boronization. Segment 1 loaded was from 1020814005 Following segments were from 1020828007.
Aug 29 2002 09:48:06:250AM	1020829002	Ron Parker	Shot 2 was also a dud. For the next shot, pulse gas increased from 27 to 31 ms EF4 current increased from -1315 to -1300
Aug 29 2002 10:13:27:723AM	1020829003	Ron Parker	Shot 3 was a dud. Next shot: Raise fill to 36 ms pulse width Decrease EF4 to -1330 Raise BR by 0.3 mT
Aug 29 2002 10:16:04:757AM	1020829004	Ron Parker	Shot 4 was a dud. No sign of plasma, even though error fields are well within usual limits. Also, pressure has been increased to 0.06 mTorr. Before next shot, we'll discharge clean in D2 for 30 minutes.
Aug 29 2002 04:53:57:847PM	1020829005	Ron Parker	Shot 5, after 30 min of ECDC, was a fizzle -- first sign of plasma today. For next shot, the fill pressure will be lowered by decreasing pulse gas width from 36 to 31 ms. Also, BR will be increase by 0.3 mT.
Aug 29 2002 11:12:49:863AM	1020829006	Ron Parker	Shot 6 fizzled, perhaps a little less anemically than in shot 5. We'll continue to reduce the fill pressure, in next shot gas pulse will be 28 ms wide.
Aug 29 2002 11:26:01:637AM	1020829007	Ron Parker	Have patience -- we're going in the right direction! We'll continue to reduce fill pressure, 25 ms width on next shot.
Aug 29 2002 05:04:58:240PM	1020829008	Ron Parker	Shot 8 ran, first shot after overnight boronization.
Aug 29 2002 04:55:14:083PM	1020829009	Ron Parker	Not surprisingly, shot 9 was a fizzle. It looks like the width of the gas pulse can be reduced a bit further, perhaps 2 ms. We'll try it for the next shot.
Aug 29 2002 12:05:57:527PM	1020829010	Ron Parker	Another fizzle, but curent rises faster. It seems close to going. No change for next shot.
Aug 29 2002 12:22:31:430PM	1020829011	Ron Parker	Shot 11 ran and looked OK. About 0.7 MW RF mainly from E port. We'll probably be in an every other or every third shot mode for a while.
Aug 29 2002 12:26:56:060PM	1020829012	Ron Parker	Shot 12 was a no power shot- EF1 Cap bank did not charge.
Aug 29 2002 12:42:32:273PM	1020829013	Ron Parker	Shot 13 ran, with sporadic RF.
Aug 29 2002 12:55:44:927PM	1020829014	Ron Parker	Shot 14 ran well. We'll continue with these shots in order to bring up the RF.
Aug 29 2002 01:07:51:293PM	1020829015	Ron Parker	Shot 15 fizzled, we're not out of the woods yet. Also, BZ seems to be gradually decreasing, now almost -1 mT at breakdown. For next shot, EF4 current will be increased to -1310 from -1330 A.
Aug 29 2002 01:24:35:973PM	1020829016	Ron Parker	Shot 16 ran well. EF4 will be set at -1320 for next shot.
Aug 29 2002 01:32:34:630PM	1020829017	Ron Parker	Shot 17 ran well. Continue to bring up RF.
Aug 29 2002 01:47:05:610PM	1020829018	Ron Parker	Shot 18 fizzled, CII influx seemed to kill it. We'll increase EF4 Current to -1310 for next shot.
Aug 29 2002 02:01:13:060PM	1020829019	Ron Parker	Shot 19 also fizzled. Possible that the gas fill pressure has dropped too low. Next shot will have the gas pulse width increased by 2 ms.
Aug 29 2002 02:15:30:167PM	1020829020	Ron Parker	Shot 20 fizzled. For next shot we'll load shot 11.
Aug 29 2002 02:25:07:450PM	1020829021	Ron Parker	Shot 21 ran, but disrupted at 0.65 s. Same shot for shot 22.
Aug 29 2002 02:51:40:800PM	1020829022	Ron Parker	Shot 22 ran, and had a H-mode with ~ 1.25 MW of RF power.
Aug 29 2002 02:52:18:957PM	1020829023	Ron Parker	Shot 23 fizzled.
Aug 29 2002 03:05:00:667PM	1020829024	Ron Parker	Shot 24 ran and had an H-mode for 0.5 s
Aug 29 2002 03:19:29:350PM	1020829025	Ron Parker	Shot 25 was a fizzle. Try again.
Aug 29 2002 03:24:41:847PM	1020829025	Ron Parker	For shot 26, the gas fill pressure will be increased by 10% to try to slow down the current rise and keep the plasma from moving out so far during startup.
Aug 29 2002 03:39:21:983PM	1020829026	Ron Parker	Shot 26 still fizzled, so the gas will be set back to its previous level.
Aug 29 2002 03:49:17:080PM	1020829027	Ron Parker	Shot 27 fizzled. Reload shot 11.
Aug 29 2002 03:59:11:427PM	1020829028	Ron Parker	Shot 28 ran, but disrupted at ~ 1.1 s Repeat shot coming up.
Aug 29 2002 04:10:51:137PM	1020829029	Ron Parker	Shot 29 ran with a reasonable H-Mode, ~ 2MW RF.
Aug 29 2002 04:24:13:960PM	1020829030	Ron Parker	Shot 30 ran with H-mode, ~ 1.7 MW RF from D&E.
Aug 29 2002 04:34:06:683PM	1020829031	Ron Parker	Shot 31 fizzled. No change for next shot.
Aug 29 2002 04:50:20:493PM	1020829032	Ron Parker	Shot 32 ran. H-mode with ~1,7 MW from D&E.
Aug 29 2002 05:01:10:843PM	1020829033	Ron Parker	Shot 33, the last shot of the day fizzled.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:06:34:907AM	Plasma	Ok
2	09:34:14:020AM	Plasma	Ok
3	09:49:07:440AM	Plasma	Ok
4	10:05:54:967AM	Plasma	Ok
5	10:52:07:597AM	Plasma	Ok
6	11:05:34:637AM	Plasma	Ok
7	11:18:26:240AM	Plasma	Ok
8	11:31:41:597AM	Plasma	Ok
9	11:44:26:887AM	Plasma	Ok
10	11:57:18:223AM	Plasma	Ok
11	12:10:13:640PM	Plasma	Ok
12	12:23:06:090PM	Plasma	Ok
13	12:33:59:143PM	Plasma	Ok
14	12:46:51:573PM	Plasma	Ok
15	12:59:53:180PM	Plasma	Ok
16	01:12:46:737PM	Plasma	Ok
17	01:25:42:680PM	Plasma	Ok
18	01:39:08:847PM	Plasma	Ok
19	01:51:52:340PM	Plasma	Ok
20	02:04:54:303PM	Plasma	Ok
21	02:18:10:813PM	Plasma	Ok
22	02:31:56:370PM	Plasma	Ok
23	02:46:41:367PM	Plasma	Ok
24	02:59:30:767PM	Plasma	Ok
25	03:13:20:777PM	Plasma	Ok
26	03:26:15:910PM	Plasma	Ok
27	03:39:08:327PM	Plasma	Ok
28	03:51:56:210PM	Plasma	Ok
29	04:04:55:017PM	Plasma	Ok
30	04:17:58:450PM	Plasma	Ok
31	04:31:05:707PM	Plasma	Ok
32	04:44:04:890PM	Plasma	Ok
33	04:57:32:540PM	Plasma	Ok