Miniproposals

Miniproposal: Date Filed: Title: First Author: Session Leader: Brian Labombard (shots 1-15) Session Leader: Bruce Lipschultz (shots 1-15)

Engineering Operator Run Comment

mp o84 fiorst run after vacc break

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:12:303PM

Author: To Be Determined

Session Leader's summary of run 950228 MP# 084 Scrape_off Layer Characterization II Physics Operator: Granetz Session Leader: LaBombard Engineering Operator: Bertolino The official goal of this run was to study the scaling of scrape-off layer conditions in single null diverted plasmas with plasma currents of 0.4, 0.6, 0.8, and 1.0 MA. However, since this run was the first attempt at plasmas after a vacuum break/maintenance period, the more immediate goal was to work out bugs and re-establish routine operation. In the end, the bugs that accumulated during the shutdown prevailed. After a very impressive start in which we were able to obtain two diverted plasmas after just 4 attempts (they looked just like the plasmas we had on Jan 17th!) the luck ran out. A variety of problems showed up including a problem with the new RAID file system. The holdup forced us to cancel the run early (shot 13) to allow the bugs to be fixed. Needless to say, we did not achieve our physics objectives. Our strategy now is to get a re-sheduled run as early as possible - but not on a tuesday! See the physics operator summary for a shot by shot commentary. The run plan was: 5.3 Tesla deuterium plasmas, no impurity gas injection, no special wall preconditioning (0) - start programming with 950202010 which is an 0.8 MA shot with very good constant strike point programming (probe 2 on outer divertor), very good scanning probe targeting, and good gaps. At first, the challenge will be to reproduce this discharge after the recent vacuum break and the recent week of mondays. (5 shots) Five key equilibrium shape parameters need to be watched during this run: inner gap > 1.5 cm, outer gap > 1.5 cm, distance to second separatrix (SSEP on EFIT scope) > 1.7 cm, constant outer divertor strike point location, and constant scanning probe target flux surface location. (1) - tune up a density ramp from NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec. Fire the scanning probe at 0.5, 0.75 and 1.0 sec. (3 shots) (2) - density ramp from NL_04 = 0.8e20 at 0.5 sec to 1.5e20 at 1 sec, fire probe (3 shots) (2a) - optional at 1.0 MA: density ramp from NL_04 = 1.0e20 at 0.5 sec to 2.0e20 at 1 sec, fire probe (3 shots) - repeat steps (1) and (2) for plasma currents of 0.6, 0.4, and 1.0 MA. (3) - for last 2 shots, return to 0.8 MA with density ramp NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec, fire probe The reality was: We got two shots at 0.8 MA. On the second one, the scanning probe collected a couple of ions.

Physics Operator Summaries

Entered: Jul 7 2004 04:36:53:253PM

Author: To Be Determined

Physics operator's summary of run 950228 (MP# 084 Scrape_off Layer Characterization II) SL: BLAB and BLIP PO: Granetz EO: Bertolino This run was the first attempt to get plasmas after a one-and-a-half week shutdown, which included two vacuum breaks. The first 4 shots had short, dirty, disruptive plasmas, with lots of carbon (and hydrogen). Shots 5 and 6 were very good diverted plasmas, on which we began tweaking the inner and outer gaps, and the density ramp. However, shot 7 fizzled for no obvious reason, and on shot 8 there was a failure of the software that creates pulse files on the disks. Shots 009 and 011 fizzled, with 011 having a 15 amp tweak to EF4 to tweak Bz. Shot 013 was set up with higher pre-fill pressure, but we never got to take the shot. The software failures that killed shot 008 also killed shots 010, 012, and 013. Josh couldn't seem to work around the problem, so after an hour of unsuccessful attempts at getting a shot off, I cancelled the remainder of the run and opted to get in a few hours of ECDC. No scientific objectives were met. The run plan and shot log follow: The run plan for tuesday 28-FEB-1994 (MP# 084 Scrape-off Layer Characterization II) is as follows: 5.3 Tesla deuterium plasmas, no impurity gas injection, no special wall preconditioning (0) - start programming with 950202010 which is an 0.8 MA shot with very good constant strike point programming (probe 2 on outer divertor), very good scanning probe targeting, and good gaps. At first, the challenge will be to reproduce this discharge after the recent vacuum break and the recent week of mondays. (5 shots) Five key equilibrium shape parameters need to be watched during this run: inner gap > 1.5 cm, outer gap > 1.5 cm, distance to second separatrix (SSEP on EFIT scope) > 1.7 cm, constant outer divertor strike point location, and constant scanning probe target flux surface location. (1) - tune up a density ramp from NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec. Fire the scanning probe at 0.5, 0.75 and 1.0 sec. (3 shots) (2) - density ramp from NL_04 = 0.8e20 at 0.5 sec to 1.5e20 at 1 sec, fire probe (3 shots) (2a) - optional at 1.0 MA: density ramp from NL_04 = 1.0e20 at 0.5 sec to 2.0e20 at 1 sec, fire probe (3 shots) - repeat steps (1) and (2) for plasma currents of 0.6, 0.4, and 1.0 MA. (3) - for last 2 shots, return to 0.8 MA with density ramp NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec, fire probe Shot 001 - Plasma, but short and dirty (I assume). Next shot, no changes. Shot 002 - Same thing. It might have been overgassed. Next shot, less gas in segment 1. Also, turn off argon enable. Shot 003 - Slightly better. Current just about reached 0.4 MA at 0.1 s. Still becomes very disruptive starting after 0.1 s. Next shot, lower density demand from nl04=1.1e20 to 0.6e20. Shot 004 - Slightly better. Lots of carbon. Still looks dirty. Next shot, no changes. Shot 005 - Good plasma. Ip=0.8 MA, nl_04=0.6e20 m-2. Duration=1.7 s. Next shot, increase CLEARIN by 0.5 cm, and RCUR by 3 mm (to keep CLEAROUT about the same. Also put in a density ramp from nl_04=0.5e20 at 0.45 s to 1.0e20 at 1.0 s. Shot 006 - Good plasma. Inner and outer gaps=2.0 cm. Density ramped as requested. SSEP=1.5 cm. Next shot, increase SSEP by raising ZXU by 0.5 cm. Shot 007 - Fizzle. Unexplained. Next shot, no changes. Shot 008 - System failure...went into PULSE, but nothing fired. There was no engineering tree created. Next shot, no changes. Shot 009 - Fizzle. Perhaps a little too much vertical field. Next shot, make Bz a little more negative by 15 amps in EF4. Shot 010 - System failure...went into PULSE, but nothing fired. There was no engineering tree created. Same thing as on shot 008. Josh & Co. are looking into it. Next shot, no changes. Shot 011 - Fizzle. Next shot, raise pre-fill from 1.6 to 2.0e-5 torr, and return EF4 demand prior to shot back to what it was before shot 010 (increase by 15 amps) Shot 012 - Disk system failure again. Next shot, no changes, try again. Shot 013 - No shot. After an hour of trying unsuccessfully to get a shot off, Josh doesn't seem to be any closer to understanding and/or solving the disk/software/MDS problems. I've decided to shutdown the run and get in several hours of ECDC. (It's not even clear that the problems will be sorted out in time for tomorrow's run.)

Session Leader Comments
Feb 28 1995 08:46:32:580AM		Brian Labombard	This run is MP#084 Scrape-off Layer Characterization II. The plan is as follows: (0) - start programming with 950202010 which is an 0.8 MA shot with very good constant strike point programming (probe 2 on outer divertor), very good scanning probe targeting, and good gaps. At first, the challenge will be to reproduce this discharge after the recent vacuum break and the recent week of mondays. (5 shots) Five key equilibrium shape parameters need to be watched during this run: inner gap > 1.5 cm, outer gap > 1.5 cm, distance to second separatrix (SSEP on EFIT scope) > 1.7 constant outer divertor strike point location, and constant scanning probe target flux surface location. (1) - tune up a density ramp from NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec. Fire the scanning probe at 0.5, 0.75 and 1.0 sec. (3 shots) (2) - density ramp from NL_04 = 0.8e20 at 0.5 sec to 1.5e20 at 1 sec, fire probe (3 shots) (2a) - optional at 1.0 MA: density ramp from NL_04 = 1.0e20 at 0.5 sec to 2.0e20 at 1 sec, fire probe (3 shots) - repeat steps (1) and (2) for plasma currents of 0.6, 0.4, and 1.0 MA. (3) - for last 2 shots, return to 0.8 MA with density ramp NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1
Feb 28 1995 08:54:15:960AM	950228001	Brian Labombard	Shot #1: Loaded shot# 950202010 - 0.2 sec plasma. 300 kA
Feb 28 1995 09:04:20:420AM	950228002	Brian Labombard	Shot #2: similar to shot 1 - 0.25 sec plasma. 300 kA
Feb 28 1995 09:27:56:760AM	950228004	Brian Labombard	Shot #4: patience is a virtue - 0.3 sec plasma. 400 kA
Feb 28 1995 09:49:07:410AM	950228005	Brian Labombard	Shot #5: very nice shot! 5 shot recovery from a vacuum break!! NL_04 is 0.6e20
Feb 28 1995 10:06:57:980AM	950228006	Brian Labombard	Shot #6: Changed inner gap, programmed a density ramp: NL_4 from 0.5e20 to 1.0e20 FSP is firing in silo - rest position is -50 mm.
Feb 28 1995 10:08:33:610AM	950228007	Brian Labombard	Shot #7: Changed SSEP. Fired scanning probe at 0.5, 0.75, 1.0 sec rest position is 5 mm. No plasma.
Feb 28 1995 10:33:09:550AM	950228008	Brian Labombard	Shot #8: problem with computer - no attempt
Feb 28 1995 10:38:45:130AM	950228009	Brian Labombard	Shot #9: fsp fired at 0.5, .75, 1.0 sec. rest position is 5.0 mm. - dud.
Feb 28 1995 11:14:44:270AM	950228010	Brian Labombard	Shot #10: shot did not go.
Feb 28 1995 11:15:05:300AM	950228011	Brian Labombard	Shot #11: dud.
Feb 28 1995 11:32:09:820AM	950228012	Brian Labombard	Shot #12: Computer problem. No shot.

Physics Operator Comments
Feb 28 1995 08:19:11:830AM		Robert Granetz	The run plan for tuesday 28-FEB-1994 (MP# 084 Scrape-off Layer Character ization II) is as follows: 5.3 Tesla deuterium plasmas, no impurity gas injection, no special wall preco nditioning (0) - start programming with 950202010 which is an 0.8 MA shot with very good co nstant strike point programming (probe 2 on outer divertor), very good scanning prob e targeting, and good gaps. At first, the challenge will be to reproduce this discharge af ter the recent vacuum break and the recent week of mondays. (5 shots) Five key equilibrium shape parameters need to be watched during this run: inner gap > 1.5 cm, outer gap > 1.5 cm, distance to second separatrix (SSEP o n EFIT scope) > 1.7 cm, constant outer divertor strike point location, and constant scanning probe ta rget flux surface location.
Feb 28 1995 08:19:26:710AM		Robert Granetz	(1) - tune up a density ramp from NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec. Fire the scanning probe at 0.5, 0.75 and 1.0 sec. (3 shots) (2) - density ramp from NL_04 = 0.8e20 at 0.5 sec to 1.5e20 at 1 sec, fire probe (3 shots) (2a) - optional at 1.0 MA: density ramp from NL_04 = 1.0e20 at 0.5 sec to 2.0e20 at 1 sec, fire probe (3 shots) - repeat steps (1) and (2) for plasma currents of 0.6, 0.4, and 1.0 MA. (3) - for last 2 shots, return to 0.8 MA with density ramp NL_04 = 0.5e20 at 0.5 sec to 1.0e20 at 1 sec, fire probe
Feb 28 1995 08:49:35:400AM	950228001	Robert Granetz	Shot 001 - Plasma, but short and dirty (I assume). Next shot, no changes.
Feb 28 1995 09:10:23:720AM	950228002	Robert Granetz	Shot 002 - Same thing. It might have been overgassed. Next shot, less gas in segment 1. Also, turn off argon enable.
Feb 28 1995 09:17:21:910AM	950228003	Robert Granetz	Shot 003 - Slightly better. Current just about reached 0.4 MA at 0.1 s. Still becomes very disruptive starting after 0.1 s. Next shot, lower density demand from nl04=1.1e20 to 0.6e20.
Feb 28 1995 09:38:06:060AM	950228004	Robert Granetz	Shot 004 - Slightly better. Lots of carbon. Still looks dirty. Next shot, no changes.
Feb 28 1995 09:50:21:510AM	950228005	Robert Granetz	Shot 005 - Good plasma. Ip=0.8 MA, nl_04=0.6e20 m-2. Duration=1.7 s. Next shot, increase CLEARIN by 0.5 cm, and RCUR by 3 mm (to keep CLEAROUT about the same. Also put in a density ramp from nl_04=0.5e20 at 0.45 s to 1.0e20 at 1.0 s.
Feb 28 1995 10:04:26:590AM	950228006	Robert Granetz	Shot 006 - Good plasma. Inner and outer gaps=2.0 cm. Density ramped as requested. SSEP=1.5 cm. Next shot, increase SSEP by raising ZXU by 0.5 cm.
Feb 28 1995 10:13:22:640AM	950228007	Robert Granetz	Shot 007 - Fizzle. Unexplained. Next shot, no changes.
Feb 28 1995 10:34:47:250AM	950228008	Robert Granetz	Shot 008 - System failure...went into PULSE, but nothing fired. There was no engineering tree created. Next shot, no changes.
Feb 28 1995 10:44:36:190AM	950228009	Robert Granetz	Shot 009 - Fizzle. Perhaps a little too much vertical field. Next shot, make Bz a little more negative by 15 amps in EF4.
Feb 28 1995 10:49:07:610AM	950228010	Robert Granetz	Shot 010 - System failure...went into PULSE, but nothing fired. There was no engineering tree created. Same thing as on shot 008. Josh & Co. are looking into it. Next shot, no changes.
Feb 28 1995 11:25:40:890AM	950228011	Robert Granetz	Shot 011 - Fizzle. Next shot, raise pre-fill from 1.6 to 2.0e-5 torr, and return EF4 demand prior to shot back to what it was before shot 010 (increase by 15 amps)
Feb 28 1995 11:36:50:960AM	950228012	Robert Granetz	Shot 012 - Disk system failure again. Next shot, no changes, try again.
Feb 28 1995 12:27:02:350PM	950228013	Robert Granetz	Shot 013 - No shot. After an hour of trying unsuccessfully to get a shot off, Josh doesn't seem to be any closer to understanding and/or solving the disk/software/MDS problems. I've decided to shutdown the run and get in several hours of ECDC. (It's not even clear that the problems will be sorted out in time for tomorrow's run.)

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:42:35:690AM	Plasma	Ok	no faults
2	08:52:08:710AM	Plasma	Ok	no faults
3	09:09:56:010AM	Plasma	Ok	no faults
4	09:19:35:030AM	Plasma	Ok	no faults
5	09:32:12:480AM	Plasma	Ok	no faults
6	09:50:00:950AM	Plasma	Ok	no faults
7	10:05:38:270AM	Plasma	Ok	no faults
8	10:14:15:970AM	Plasma	Bad	No pulse - engineering not inc.
9	10:33:23:460AM	Plasma	Ok	no faults
10	10:46:11:350AM	Plasma	Bad	camac did not trigger supplies
11	11:10:12:940AM	Plasma	Ok	no faults
12	11:29:41:360AM	Plasma	Bad	camac did not fire supplies
13	11:41:34:500AM	Test	Ok	testing diskquota fix OK
14	02:31:14:140PM	Test	Ok	seems to be working
15	02:45:24:410PM	Test	Ok