Alcator C-Mod Run 931029 Information

Miniproposals

Miniproposal:

Date Filed:

Title:

First Author:

Session Leader: Tom Luke (shots 35-41)

Miniproposal: 059

Date Filed: 6/6/1994

Title: ICRF Heating (PRF>1 MW)

First Author: Yuichi Takase

Session Leader: Yuichi Takase (shots 1-34)

Operators
Session leader(s):	Yuichi Takase,Tom Luke
Physics operator(s):	Steve Golovato,Joseph Snipes
Engineering operator(s):	Vinny Bertolino

Engineering Operator Run Comment
ICRF Heating

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:09:697PM

Author: To Be Determined

931029

Part A (RF)

SL: Takase
PO: Golovato
EO: Bertolini

Part B (modulated gas puff / pellet)

Session_Leader: Thomas Luke
Physics Operator: Steve Golovato, Joe Snipes
Engineering Operator: Vinnie Bertolino

Physics Run Summary 931029 (Part A)

The objective for the rf part of the run was:
1. Move antenna and limiter closer to separatrix and find out the
minimum necessary gap for effective divertor operation.
2. Move plasma in, with limiter at R=91cm (position of new limiters).
3. Raise density with divertor puffing and look for heating.
4. Push power
5. Lower TF to push resonance out of the plasma.
6. Inject rf into H-mode (if H-mode happens by itself, but will not
attempt to produce one)

1. Scan was performed on shots 001-008, but with R_lim=91cm the plasma
we were running touched the outboard limiter and disrupted. A different
start-up scenario is needed to address this question. It appeared that
rf power is affecting the divertor operation.
2. Attempt was made to push the antenna in by reducing R_cur and R_in by
1cm on shots 009-011, but encountered the same start-up problem.
3. and 4. The rest of the run was dedicated to these objectives.
We have observed heating on both ions and electrons, and possibly on
magnetic stored energies, but indications on magnetics were less
convincing. We have injected 800kW on shots on several shots
(shots 018, 019, 022, 024, 030, 031). The injected rf power exceeded
1MW momentarily on shots 019 and 031.
5. and 6. These objectives were not persued.

shot
001 R_lim=93 R_ant=94 H puff 70V X .05
good shot, Rgap=3cm, nel=8
002 R_lim=92.5 R_ant=93.5
runaway shot, disrupt @ .37
003 R_lim=92 R_ant=93
disrupt @ .18
004 R_lim=93 R_ant=93.5
disrupt @ .32
005 R_lim=93 R_ant=93.5
disrupt @ .27, lots of Moly early in the shot
006 R_lim=93 R_ant=94
good shot
007 R_lim=92 R_ant=93
good shot
008 R_lim=91 R_ant=92
disrupt @ .17
009 R_lim=91 R_ant=92, R_cur and R_in moved 1cm in
no shot
010 same
disrupt @ .26
011 R_lim=92 R_ant=93
disrupt
012 R_lim=92 R_ant=93, plasma back to original position (shot 007)
good shot
013 R_lim=91.5 R_ant=92.5
disrupt @ .19, plasma touches outer limiter @ .14
014 R_lim=91.5 R_ant=92.5
disrupt @ .19
015 R_lim=93 R_ant=94
good shot
016 R_lim=93 R_ant=94, divertor D (19psi) puff on (Delta p = 60 Torr)
disrupt @ .19
017 R_lim=93 R_ant=94, divertor D puff on
disrupt @ .18
018 R_lim=93 R_ant=94, divertor D puff on
good shot, nel ramping 8-14e19, rf interrupts .9MW
019 R_lim=93 R_ant=94, divertor D puff on
good shot, high power, EFIT Wp went up?
020 R_lim=93 R_ant=94, divertor D puff on
good shot, rf interrupts
021 R_lim=93 R_ant=94, divertor D puff on
disrupt @ .15
022 R_lim=93 R_ant=94, divertor D puff on
good shot, rf interrupts
023 R_lim=93 R_ant=94, divertor D puff on
no shot
024 R_lim=93 R_ant=94, divertor D puff on
good shot, rf almost OK
025 R_lim=93 R_ant=94, divertor D puff on (Delta p = 75 Torr)
good shot, rf interrupts (mistuned), nel ramp 9-17e19
026 R_lim=93 R_ant=95, divertor D puff on
good shot, 700kW
027 R_lim=93 R_ant=95, divertor D puff on (Delta p = 90 Torr)
fizzle
028 R_lim=93 R_ant=95, divertor D puff on
good shot, short rf
029 R_lim=93 R_ant=94, divertor D puff on (Delta p = 60 Torr)
good shot
030 R_lim=93 R_ant=94, divertor D puff on for shorter time
good shot
031 R_lim=93 R_ant=94, divertor D puff on for shorter time
good shot
032 R_lim=93 R_ant=94, divertor D puff on for shorter time
runaway, short shot
033 R_lim=93 R_ant=94, divertor D puff on for shorter time
fizzle
034 R_lim=93 R_ant=94, divertor D puff on for shorter time
disrupt @ .17

Physics Run Summary 931029 (Part B)

Again , this is another attempt to finish MP 030. AFter the RF portion of
the run, the machine seems to be behaving relatively well and we will try
to do the modulated gas puffs again. The current will be 800 kA and we
will vary the base nl between 5.0e19 to 5.0e20. Again pellets will be used
for the higher densities. The shots went fairly well. We had 4 good shots
out of 7. Got some results but the density limit still eludes us.

shot

35 fizzle

36 good shot, got nl=8.0e19, 1.2s

37 good shot. nl=1.0e20, small puffs, can't see them.

38 good shot, no pellet but clearly see puffs

39 great shot, pellet at 500 ms. nl up to 1.5e20

40 2 pellets, D2 at 400, Li at 500. Li pellet killed shot. Possible Mo
injections before pellets was deteriorating conditions.

41 2 D2 pellets at 400 and 600. Again,2nd pellet killed plasma.

Well, that's all folks. It was a great fall run and I thank everyone who
stayed late to help me get some data. Thank you and see you in the spring!

Physics Operator Summaries

Session Leader Comments

Oct 29 1993 09:27:03:220AM Yuichi Takase RF run followed by Tom Lukes (if things go well)

Today's program:
1. Move antenna and limiter closer to separatrix and find out the
minimum necessary gap for effective divertor operation.
2. Move plasma in, and limiter in to R=91cm (position for new limiters).
3. Raise density with divertor puffing.
4. Push power
5. Lower TF to push resonance out of the plasma.
6. Inject rf into H-mode (we will not make deliberate attempt to
produce H-mode, but it may happen by itself).

Physics Operator Comments

Oct 29 1993 07:39:36:090PM 931029038 Joseph Snipes Shot 39
No changes except D pellet (2 x 10**20 atoms) at 0.5 s.
Good shot. Disrupted at 0.9 s.

Oct 29 1993 07:57:33:420PM 931029038 Joseph Snipes Shot 40
Raised first three late gas puffs to 65 V. D pellet at 0.4 s, Li pellet
at 0.5 s.
Disrupted at Li pellet.

Oct 29 1993 07:58:16:040PM 931029040 Joseph Snipes Shot 40
Raised first three late gas puffs to 65 V. D pellet at 0.4 s, Li pellet
at 0.5 s.
Disrupted at Li pellet.

Oct 29 1993 08:06:52:500PM 931029040 Joseph Snipes Shot 41
Last shot of the year. D pellets at 0.4 and 0.65 s.
Disrupted at 0.65 s.

Oct 29 1993 08:14:08:720PM 931029040 Joseph Snipes Shot 41
Last shot of the year. D pellets at 0.4 and 0.65 s.
Disrupted at 0.65 s resulting from the second D pellet.
Toast to teamwork!

Engineering Operator Comments

Shot Time Type Status Comment

1 09:10:30:880AM Plasma Ok Plasma shot no faults.

2 09:25:47:170AM Plasma Ok Plasma shot No Faults.

3 09:38:48:660AM Plasma Ok Plasma shot No Faults.

4 09:54:35:080AM Plasma Ok Plasma shot NO faults

5 10:10:53:690AM Plasma Ok Plasma shot NO faults.

6 10:28:02:150AM Plasma Ok Plasma shot No faults.

7 10:44:04:710AM Plasma Ok Plasma shot No faults.

8 11:01:22:740AM Plasma Ok Plasmsa shot NO faults.

9 11:18:39:510AM Plasma Bad ack failure with no latched fault on the state PC.

10 11:37:59:320AM Plasma Ok comm fail oh1 and oh2s due to disruption

11 12:05:22:630PM Plasma Ok no faults

12 12:19:48:270PM Plasma Ok no faults

13 12:34:21:920PM Plasma Ok no faults

14 12:49:23:420PM Plasma Ok no faults

15 01:11:05:740PM Plasma Ok no faults on power supplies, alternator is changing modes from remote to

16 01:26:45:050PM Plasma Ok no faults

17 01:45:05:900PM Plasma Ok no faults

18 01:58:45:360PM Plasma Ok no faults

19 02:14:26:610PM Plasma Ok no faults

20 02:30:44:460PM Plasma Ok no faults

21 02:47:05:370PM Plasma Ok no faults

22 03:02:43:690PM Plasma Ok no faults

24 03:30:29:760PM Plasma Ok no faults

25 03:48:17:570PM Plasma Ok no faults

26 04:04:06:160PM Plasma Ok no faults

27 04:27:12:920PM Plasma Ok no faults

28 04:42:31:130PM Plasma Ok disruption induced comm failures

29 04:57:26:810PM Plasma Ok no faults

30 05:13:28:210PM Plasma Ok no faults

31 05:28:25:270PM Plasma Ok no faults

32 05:42:59:720PM Plasma Ok no faults

33 05:58:25:830PM Plasma Ok no faults

34 06:11:55:480PM Plasma Ok no faults

35 06:27:39:580PM Plasma Ok no faults

36 06:45:06:220PM Plasma Ok no faults

37 06:59:15:720PM Plasma Ok disruption induced comm fails on PF supplies

38 07:16:29:640PM Plasma Ok no faults

39 07:31:40:910PM Plasma Ok no faults

40 07:47:28:930PM Plasma Ok no faults

41 08:03:08:180PM Plasma Ok PLASMA -- LAST SHOT OF 1993!!!!!!!

Session Leader Comments
Oct 29 1993 09:27:03:220AM		Yuichi Takase	RF run followed by Tom Lukes (if things go well) Today's program: 1. Move antenna and limiter closer to separatrix and find out the minimum necessary gap for effective divertor operation. 2. Move plasma in, and limiter in to R=91cm (position for new limiters). 3. Raise density with divertor puffing. 4. Push power 5. Lower TF to push resonance out of the plasma. 6. Inject rf into H-mode (we will not make deliberate attempt to produce H-mode, but it may happen by itself).

Physics Operator Comments
Oct 29 1993 07:39:36:090PM	931029038	Joseph Snipes	Shot 39 No changes except D pellet (2 x 10**20 atoms) at 0.5 s. Good shot. Disrupted at 0.9 s.
Oct 29 1993 07:57:33:420PM	931029038	Joseph Snipes	Shot 40 Raised first three late gas puffs to 65 V. D pellet at 0.4 s, Li pellet at 0.5 s. Disrupted at Li pellet.
Oct 29 1993 07:58:16:040PM	931029040	Joseph Snipes	Shot 40 Raised first three late gas puffs to 65 V. D pellet at 0.4 s, Li pellet at 0.5 s. Disrupted at Li pellet.
Oct 29 1993 08:06:52:500PM	931029040	Joseph Snipes	Shot 41 Last shot of the year. D pellets at 0.4 and 0.65 s. Disrupted at 0.65 s.
Oct 29 1993 08:14:08:720PM	931029040	Joseph Snipes	Shot 41 Last shot of the year. D pellets at 0.4 and 0.65 s. Disrupted at 0.65 s resulting from the second D pellet. Toast to teamwork!

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:10:30:880AM	Plasma	Ok	Plasma shot no faults.
2	09:25:47:170AM	Plasma	Ok	Plasma shot No Faults.
3	09:38:48:660AM	Plasma	Ok	Plasma shot No Faults.
4	09:54:35:080AM	Plasma	Ok	Plasma shot NO faults
5	10:10:53:690AM	Plasma	Ok	Plasma shot NO faults.
6	10:28:02:150AM	Plasma	Ok	Plasma shot No faults.
7	10:44:04:710AM	Plasma	Ok	Plasma shot No faults.
8	11:01:22:740AM	Plasma	Ok	Plasmsa shot NO faults.
9	11:18:39:510AM	Plasma	Bad	ack failure with no latched fault on the state PC.
10	11:37:59:320AM	Plasma	Ok	comm fail oh1 and oh2s due to disruption
11	12:05:22:630PM	Plasma	Ok	no faults
12	12:19:48:270PM	Plasma	Ok	no faults
13	12:34:21:920PM	Plasma	Ok	no faults
14	12:49:23:420PM	Plasma	Ok	no faults
15	01:11:05:740PM	Plasma	Ok	no faults on power supplies, alternator is changing modes from remote to
16	01:26:45:050PM	Plasma	Ok	no faults
17	01:45:05:900PM	Plasma	Ok	no faults
18	01:58:45:360PM	Plasma	Ok	no faults
19	02:14:26:610PM	Plasma	Ok	no faults
20	02:30:44:460PM	Plasma	Ok	no faults
21	02:47:05:370PM	Plasma	Ok	no faults
22	03:02:43:690PM	Plasma	Ok	no faults
24	03:30:29:760PM	Plasma	Ok	no faults
25	03:48:17:570PM	Plasma	Ok	no faults
26	04:04:06:160PM	Plasma	Ok	no faults
27	04:27:12:920PM	Plasma	Ok	no faults
28	04:42:31:130PM	Plasma	Ok	disruption induced comm failures
29	04:57:26:810PM	Plasma	Ok	no faults
30	05:13:28:210PM	Plasma	Ok	no faults
31	05:28:25:270PM	Plasma	Ok	no faults
32	05:42:59:720PM	Plasma	Ok	no faults
33	05:58:25:830PM	Plasma	Ok	no faults
34	06:11:55:480PM	Plasma	Ok	no faults
35	06:27:39:580PM	Plasma	Ok	no faults
36	06:45:06:220PM	Plasma	Ok	no faults
37	06:59:15:720PM	Plasma	Ok	disruption induced comm fails on PF supplies
38	07:16:29:640PM	Plasma	Ok	no faults
39	07:31:40:910PM	Plasma	Ok	no faults
40	07:47:28:930PM	Plasma	Ok	no faults
41	08:03:08:180PM	Plasma	Ok	PLASMA -- LAST SHOT OF 1993!!!!!!!