Alcator C-Mod Run 1000914 Information

Miniproposals

Miniproposal: 278

Date Filed: 9/5/2000

Title: ELMs and EDA in low density H-modes

First Author: Amanda Hubbard

Session Leader: Amanda Hubbard (shots 1-25)

Operators
Session leader(s):	Amanda Hubbard
Physics operator(s):	Robert Granetz
Engineering operator(s):	Bill Parkin,Bill Cochran,Ed Fitzgerald

Engineering Operator Run Comment
etz SL Hubbard EO Fitzgerald,Cochran,Parkin

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:24:850PM

Author: To Be Determined

Run Summary for Thurs, Sept 14th, 2000

Session Leader: Amanda Hubbard
Physics Operator: Bob Granetz
Eng. Ops. : Bill Parkin
RF Ops.: Rejean Boivin, John Goetz, Gerd Schilling et al

MP 278 -- ELMs and EDA in low density H-modes

Goals:

Clarify the role of density on the EDA/ELM-free boundary.

Investigate the ELMs previously observed in low density operation.

Planned Shot sequence:

1) Start at 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. RF ramped to 1.5 MW. ELM-free
H-mode is anticipated at this low density. If it's EDA instead, then lower
density some more.

2) Increase Prf, shot-to-shot. Look for ELMs and trends in grad-P (5 shots)

3) Slowly increase nl_04 to 1e20 m-2. Monitor EDA signatures, especially
fluctuations. At each density, use 1 slow Prf ramp (to give L-H threshold
and time evolution) and 1-2 shots with higher, fixed Prf to maximize grad-P
and chance of triggering ELMs.

Anticipate 5 densities, 2-3 shots each (15 shots)

4) If time permits, raise Ip to 1 MA (where EDA is more marginal) and repeat
part of density scan to see if there is a "fixed" density limit or if there
is an interdependence of q and ne.

Results:

This run went very well. We carried out practically all of the run plan,
and obtained most of the desired results. Most of the day was spent on
the planned density scan at 800 kA. It was conclusively demonstrated and
well documented that there is indeed a threshold in target density for
getting EDA H-modes. For a target density of nel_04 of 0.6e20 m-2 or lower,
H-modes were ELM-free; at higher density they were EDA. There seems to be
a progressive onset of EDA with increasing density, as evidenced by Dalpha
levels, particle transport
(rate of ne and radiation rise) and density fluctuations. Both diagnostics
got very nice data showing the disappearance of coherent fluctuations in
ELM-free H-modes and their appearance in EDA; some nice comparisons between
the regimes were found for example on shots 12 (ELM-free vs EDA) and 16
(weak vs strong EDA). Hopefully a correlation of transport and mode amplitude
and perhaps frequency will be possible.

The RF performed very well, coupling up to 2.8 MW from D and E port on most
shots, and at a variety of densities and requested waveforms. This turned out
to be required, as the window for ELM-free operation was close to the low
density limit for H-mode, and thresholds were about 2 MW of RF. There was
thus not much room for power scans. Heating was particularly impressive at
low density. Many thanks to the RF crew!
When density was lowered to 3-4e19m-2, H-modes became very short and
weak as found on 1000613. (eg shots 6,8,9)

The ELM-free H-modes showed quite impressive performance, with core Te and Ti
both up to 5 keV and pedestal Te ~900 eV. Stored energies were up to
180 kJ, and H-factors ~2.5-3. The best examples were shots 10,11,12,14,15
(800 kA) and 22,23 (1 MA). Ian reports 'phenomenally fast' edge rotation,
up to 100 km/sec vs usual 40 km/sec, from analysis of edge fluctuations.
Edge TS measured steep pedestal Te gradients, over 200 keV/m; one might
speculate these are related. However, as is usually found in ELM-free,
impurities tended to accumulate, eroding the pedestal, and the good performance
was transient.

EDA H-modes were steady state but did have rather lower confinement, with
stored energy ~140 kJ and H-factors ~ 1.3-1.4. Since the heating is
presumably similar, the cause of this increased energy transport bears
investigation. EDA shots were 13,16,19 (800 kA) and 24 (1 MA). Several
ELM-free shots had subsequent EDA phases, a few were hard to classify. The
density threshold was not markedly different at 1 MA vs 800 kA, however the
H-mode power threshold was much lower (PRF 1 MW vs 2 MW) at the same density.
Several shots used slow power ramps, which should give good data for LH
thresholds and studies of pedestal evolution at different densities.

One goal of running ELM-free plasmas was to investigate whether they had any
large ELMs, as seen on June 13. Despite the high pedestals, no evidence of
ELMs or unexplained HL transitions was seen; all H-modes ended due to high
radiation. Collisionality was undoubtedly low, but pressure gradients
measured by edge TS apparently did not exceed our usual range; a stability
analysis would be interesting.

Details:
----------------------------------------------------------------------------
1000914002 hubbard SESSION_LEADER Sep 14 2000 11:04:39:340AM
nel_01 5.2e19; only 1.1 MW RF. L-mode
----------------------------------------------------------------------------
1000914003 hubbard SESSION_LEADER Sep 14 2000 11:03:15:763AM
Late H-mode 1.2 sec; took 2.1 MW power. nel-01 0.6e19m-2.
Brief ELM-free period, evolving to EDA. Too late for fluctuation data.
Need to raise RF power earlier.
----------------------------------------------------------------------------
1000914004 hubbard SESSION_LEADER Sep 14 2000 11:01:02:326AM

H-mode; took 2.6 MW power. nel-01 0.8-1.6e19m-2.

Brief ELM-free period, evolving to EDA. Confirmed by fluctuation data.
Need to reduce ne some more
----------------------------------------------------------------------------
1000914005 hubbard SESSION_LEADER Sep 14 2000 10:31:37:576AM
Dropped density to nel_1 ~6e19m-2. Got very late H-mode; it took 2.8 MW!

Looks like it starts ELM-free, with periods of ELMs or EDA. Too late for
fluctuation data.
----------------------------------------------------------------------------
1000914006 hubbard SESSION_LEADER Sep 14 2000 10:49:09:983AM

A series of several ELM-free H-mode was followed by one with EDA (and higher
starting nel~8e19).
This was confirmed by very clear fluctuation signals on the PCI and
reflectometer.

Radiation, however, went up fast in ELM-free, eroding the pedestals.

Repeat this one.
----------------------------------------------------------------------------
1000914007 hubbard SESSION_LEADER Sep 15 2000 2:45:37:840PM

Lower RF power; L-mode
----------------------------------------------------------------------------
1000914008 hubbard SESSION_LEADER Sep 14 2000 11:25:13:513AM
. . . . . . . . . . . . . . . . . . . .
Starting density is down to 3e19m-3. H-modes are getting very unclear; hardly
any density response,
and just a brief Te rise.

Still core Te's up to 4keV!

For next shots, start slowly raising density. nel 4e19 for shot 9
----------------------------------------------------------------------------
1000914009 hubbard SESSION_LEADER Sep 14 2000 11:55:36:733AM
. . . . . . . . . . . . . . . . . . . .
Starting density 4e19m-3.
UP TO 5keV early in shot. RF still doing nicely, ~ 3 MW.

A number of H-modes, but very short, not clear on type.

Early ones have te8 to 800 eV, little ne rise.

Later ones have ne rise, but modest Tedge.
-----------------------------------------------------------------------------
1000914010 hubbard SESSION_LEADER Sep 15 2000 2:46:46:873PM
. . . . . . . . . . . . . . . . . . . .
Starting density 5e19m-3.

Got a nice, longer ELM-free H-mode early (0.61 -0.68 seconds).
Impressive pedestal. Te8 to 900 eV. Te0 to 4.8 keV. There is some saturation
on MIchelson and GPC Ch 2;
has probably been there a few shots.

Repeat, moving various fluctuation diagnostics earlier to look for any ELMs
(none apparent)
-----------------------------------------------------------------------------
1000914011 hubbard SESSION_LEADER Sep 15 2000 2:48:42:013PM
. . . . . . . . . . . . . . . . . . . .
Repeat shot 10, increasing power earlier to move H-mode earlier.

Similar ELM-free H-mode, with NO edge fluctuations on PCI or reflectometer.
-----------------------------------------------------------------------------
1000914012 hubbard SESSION_LEADER Sep 14 2000 1:03:10:810PM
. . . . . . . . . . . . . . . . . . . .
Starting density 6e19m-3.

Series of decent H-modes. Ist ELM-free, just a hint of fluctuations late
2nd slight D-alpha rise, weak fluctn appears
3rd more EDA.

All appears to confirm role of target density in fluctns as well as Dalpha.
-----------------------------------------------------------------------------
1000914013 hubbard SESSION_LEADER Sep 14 2000 3:32:02:793PM
. . . . . . . . . . . . . . . . . . . .
Starting density 7e19m-3. Still nice steady RF.

Series of decent H-modes. All are now EDA, based on both D-alpha and PCI
fluctuation,
which is MUCH stronger than on shot 6. Looks like we've found our EDA
threshold!
Particle transport

Next shot; back to target 6e19 m-3 ramping RF power,
-----------------------------------------------------------------------------
1000914014 hubbard SESSION_LEADER Sep 14 2000 3:47:32:500PM
. . . . . . . . . . . . . . . . . . . .
Back to starting density 6e19m-3. RF power ramped. Threshold 1.8 MW; still
high.

2 H-modes. The first shows a hint of fluctuations on PCI, mainly ELM-free.
2nd EDA

-----------------------------------------------------------------------------
1000914015 hubbard SESSION_LEADER Sep 14 2000 3:48:39:436PM
. . . . . . . . . . . . . . . . . . . .
Back to starting density 6e19m-3. RF power reduced to 2 MW.

Not very different from higher power; a weak hint of EDA fluctuations, a bit
higher D-alpha.

Next shot: target 8e19, power ramped.
-----------------------------------------------------------------------------
1000914016 hubbard SESSION_LEADER Sep 14 2000 3:49:40:873PM
. . . . . . . . . . . . . . . . . . . .
Starting density 8e19m-3. RF power ramped 1-2.8 MW, as requested,

Two H-modes, both EDA but the second is much steadier. Interestingly, PCI
shows fluctuations
are weaker in the first, and only start after a delay. The second, steadier
EDA has much stronger
fluctuations; seems to be a quantitative correlation with particle transport.

The bad news is energy transport is also dropping; only H~1.3 vs 2.5 early in
day.
-----------------------------------------------------------------------------
1000914017 hubbard SESSION_LEADER Sep 14 2000 3:52:04:733PM
. . . . . . . . . . . . . . . . . . . .
Starting density 9e19m-3. RF power ramped 1-2.8 MW, as requested,

One long, quite steady EDA.
-----------------------------------------------------------------------------
1000914018 hubbard SESSION_LEADER Sep 14 2000 3:52:52:186PM
. . . . . . . . . . . . . . . . . . . .
Starting density 1.1e19m-3. RF power lower; L-mode.

-----------------------------------------------------------------------------
1000914019 hubbard SESSION_LEADER Sep 14 2000 3:51:26:340PM
. . . . . . . . . . . . . . . . . . . .
Target 1.1e19. Ramped RF, steady EDA.

This finished 800 kA density scan.

Now go to 1 MA, low density.

-----------------------------------------------------------------------------
1000914020 hubbard SESSION_LEADER Sep 14 2000 3:50:50:903PM
. . . . . . . . . . . . . . . . . . . .
1 MA. Target 6e19m-2.

Ramped RF. Nice series of H-modes. 1st is ELM-free, no PCI fluctuation.
2nd is EDA,
clear fluctuation.

Next shot: same density, steady RF.

-----------------------------------------------------------------------------
1000914021 hubbard SESSION_LEADER Sep 14 2000 4:12:31:780PM
. . . . . . . . . . . . . . . . . . . .
Target still 6e19 m-2; actual a bit higher?

Level 2.6 MW; some trips late.
2 H-modes, type not so clear. ELM-free or weak eda??

Lower target for next shot.
-----------------------------------------------------------------------------
1000914022 hubbard SESSION_LEADER Sep 14 2000 4:14:34:606PM
. . . . . . . . . . . . . . . . . . . .
Target 5e19. 2 H-modes. 1st definitely ELM-free. No fluctuations, Te8 840
eV, 180 kJ

Later Weak EDA (late fluctns); Teped 413 eV, 114 kJ. Much lower confinement in
EDA, all day.
-----------------------------------------------------------------------------
1000914023 hubbard SESSION_LEADER Sep 14 2000 4:34:49:670PM
. . . . . . . . . . . . . . . . . . . .
Target 7e19. 4 H-modes. 1st still looks fairly ELM-free; possibly weak EDA
Te8 730 eV, 173 kJ

Later EDA H-modes; Teped 385 eV, 132 kJ.
-----------------------------------------------------------------------------
1000914024 hubbard SESSION_LEADER Sep 14 2000 5:45:17:670PM
. . . . . . . . . . . . . . . . . . . .
Target 7e19. Did between shot ECDC. H-mode Looks a bit more EDAish, but still
weak.

RF trips early,.

Physics Operator Summaries

Entered: Jul 7 2004 04:37:12:020PM

Author: To Be Determined

Physics operator summary for run 1000914:

MP 278 -- ELMs and EDA in low density H-modes

Session leader: Amanda Hubbard
Physics operator: R. Granetz
Engineering operators: E. Fitzgerald/W. Parkin

Summary: It was a good run, we got through everything in the run plan.
Both the machine and the D and E antennas worked well all day. We
were able to run down to nl_04=3e19 m-2. H/D was generally 10% or
higher today, but the RF seemed to do a good job of heating
anyway. See Amanda's run summary for more information on the
ELMfree and EDA H-modes at low density. No obvious Type-I ELMs
were seen.

Scorecard: 23 plasmas
2 fizzles
0 dud
0 tests
0 aborted
----------
25 total

-------------------------------------------------------------------------------

Engineering setup for Thursday, 14 September 2000:

Overnight ECDC in HELIUM, stopping 1-2 hours prior to the run.

Run begins at 9:00 and ends at 17:00.

Power system setup as on 1000913005.

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid enabled
fill B-side upper with 35 psi of He Hybrid DISABLED (Yes, HELIUM)
(available for between-shot ECDC)
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 will be DISABLED for the beginning of the run; may enable later.

-------------------------------------------------------------------------------

Run plan for Thursday, 14 September 2000:

MP 278 -- ELMs and EDA in low density H-modes

Session leader: Amanda Hubbard
Physics operator: R. Granetz

Goals:

Clarify the role of density on the EDA/ELM-free boundary.

Investigate the ELMs previously observed in low density operation.

Shot sequence:

1) Start at 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. RF ramped to 1.5 MW. ELM-free
H-mode is anticipated at this low density. If it's EDA instead, then lower
density some more.

2) Increase Prf, shot-to-shot. Look for ELMs and trends in grad-P (5 shots)

3) Slowly increase nl_04 to 1e20 m-2. Monitor EDA signatures, especially
fluctuations. At each density, use 1 slow Prf ramp (to give L-H threshold
and time evolution) and 1-2 shots with higher, fixed Prf to maximize grad-P
and chance of triggering ELMs.

Anticipate 5 densities, 2-3 shots each (15 shots)

4) If time permits, raise Ip to 1 MA (where EDA is more marginal) and repeat
part of density scan to see if there is a "fixed" density limit or if there
is an interdependence of q and ne.

-------------------------------------------------------------------------------

Overnight ECDC in He

Hybrid coldstart done; no errors found

Loaded shot 1000913005 (segment 1 from 1000913016) and reduced Ip to
0.8 MA and nl_04 to 0.5e20 m-2. Remove waggle in Btor. Add 2 ms to
pre-fill puff.

-------------------------------------------------------------------------------

Shot 01 -- Fizzle. Pre-fill pressure was too low (due to He ECDC). Main video
cameras have no synch signal. Jim Terry needs cell access to fix.

Next shot: add 5 ms to pre-fill puff.

Shot 02 -- Plasma. Good shot. Ip=0.8 MA, Bt=5.4 T, nl_04=0.5e20 m-2, as
requested. RF ramped, but started faulting around 1 MW. There
was some heating, but no H-mode.

Next shot: lower Br0 by 0.5 mT and increase IC_EF4 by +10 amps.
Try for a little higher RF power.

Shot 03 -- Plasma. Good shot. nl_04=5.5-6e20 m-2. Got an H-mode which
briefly started as ELMfree before changing to EDA. Prf ramped
up to 2.0 MW and then leveled off. Pthreshold=2 MW. Strike point
is almost on the floor.

Next shot: raise ZXL by 5 mm. Ramp RF to 2 MW earlier in the shot.

Shot 04 -- Plasma. Good shot. nl_04=0.7e20 m-2. The increase in the density
is coming from the RF. EDA H-mode (starting briefly as ELMfree).

Next shot: lower target density to nl_04=0.3e20 m-2 and lower the
pre-programmed valve voltage also.

Shot 05 -- Plasma. Good shot. nl_04=3-4e19 m-2 target, rising to 6e19 m-2
during the RF just before H-mode. Prf ramps from 1.5 to 2.8 MW.
Got a short H-mode at the highest power. H/D is noisy (because
of the low signals), and varies up to 12%

Next shot: take 1 ms off pre-fill puff. Turn RF power on high
right from the start.

Shot 06 -- Plasma. Good shot. Target nl_04=3e19 m-2. These have to be the
weirdest H-modes I've ever seen. Core x-ray brightness is
saturating at 150 kW/m2 (Peak xray emissivity about 1.5-2 MW/m3 !!)
Amanda likes this. Prf=2.6-2.9 MW. H/D=10% There's a small
glowing spot showing up on the inboard wall midplane at J or K.
My guess is it's a broken tile.

Next shot: enable DNB gate valve. DNB will fire after t=1.4 s.
Add 0.3 mT to Br0.

Shot 07 -- Plasma. Good shot. Only one transmitter fired. No H-modes.
nl_04=3-3.5e19 m-2.

Next shot: Try RF again. Decrease pre-fill by 1 ms again, increase
IC_EF4 by +5 amps.

Shot 08 -- Plasma. Disrupted at t=1.25 s. I think it's due to an injection
at t=1.24 s. Target nl_04=2.9e19 m-2. Prf=2.8 MW.

Next shot: increase nl_04 to 4e19 m-2. Decrease pre-fill by another
1 ms.

Shot 09 -- Plasma. Good shot. Target nl_04=4e19 m-2. More of these little
ratty H-modes. And lots of core x-ray emissivity. John Rice
confirms that there's loads of molybdenum. Prf=2.8 MW.

Next shot: increase target density to nl_04=5e19 m-2.

Shot 10 -- Plasma. Good shot. Target nl_04=5e19 m-2. First H-mode was a nice
ELMfree one. Prf=2.8 MW.

Next shot: repeat, and set up some fast windows on magnetics,
PCI, reflectometer, and xtomo starting at t=0.6 s.

Shot 11 -- Plasma. Good shot. Looks like a repeat of the previous shot.
First H-mode is ELMfree.

Next shot: increase target nl_04 to 6e19 m-2.

Shot 12 -- Plasma. Good shot. Some ELMfree H-modes, some EDA H-modes.
H/D=8-12%. Prf=2.7 MW.

Next shot: increase target density to nl_04=0.7e20 m-2.

Shot 13 -- Plasma. Good shot. Looks like all EDA H-modes, as Amanda
anticipated.

Next shot: decrease target density back to nl_04=0.6e20 m-2 (as
on shot 12) and look for ELMfree H-mode to reappear.

Shot 14 -- Plasma. Good shot. Might be an ELMfree H-mode on this one.
RF was ramped from 1.0 to 2.8 MW. Target nl_04=0.6e20 m-2.

Next shot: set Prf to 2 MW (steady)

Shot 15 -- Plasma. Good shot. Prf=2.0 MW from t=0.55 to 1.40 s. H/D=10-11%.

Next shot: Raise target density to nl_04=0.8e20 m-2. Also, ramp the
RF up to 2.8 MW.

Shot 16 -- Plasma. Good shot. Prf ramps from 1.0 to 2.8 MW.

Next shot: Raise target density to nl_04=0.9e20 m-2.

Shot 17 -- Plasma. Good shot. One long EDA H-mode. There was an injection
at t=1.2 s which degrades things somewhat.

The bright spot on the inboard wall has not been seen since we
started raising the density several shots ago. Chris Boswell has
magnified the CCD image and has determined that the bright spot
spanned parts of two tiles, and therefore it's probably not a broken
tile. Chris also noticed that the K-port midplane limiter was
getting very bright, so he's convinced me that the bright spot on
the inboard wall was actually a specular reflection of a hot spot
on the K-port midplane limiter. At the higher densities, the
limiter is not being heated as much.

Next shot: raise target density to nl_04=1.1e20 m-2

Shot 18 -- Plasma. Good shot. No H-modes. Only had E-port transmitter,
Prf <= 1.0 MW. Target nl_04=1.0e20 m-2.

Next shot: repeat with both RF transmitters.

Shot 19 -- Plasma. Good shot. One long steady EDA H-mode. H/D=9%.
Prf ramped up to 2.5 MW.

Next shot: increase Ip to 1.0 MA and decrease nl_04 to 0.6e20 m-2.

Shot 20 -- Plasma. Good shot. Ip=1.0 MA. Target nl_04=6.7e19 m-2. First
H-mode looks ELMfree. Prf ramps from 1.0 to 2.3 MW. The ELMfree
H-mode occurs much earlier in the RF ramp, so it's obvious that
the higher current gets H-mode at a lower power threshold.

Next shot: no PCS changes. Tune RF.

Shot 21 -- Plasma. Good shot. Prf=2.6 MW, but it faulted early. 2 H-modes.
H/D=10%.

Next shot: decrease nl_04 to 0.5e20 m-2. Also add -5 amps to
IC_EF4.

Shot 22 -- Plasma. Good shot. First H-mode is ELMfree. Prf=2.6 MW.
H/D=10-12%, but it's noisy.

Next shot: raise nl_04 to 0.7e20 m-2.

Shot 23 -- Plasma. Good shot. Target nl_04=0.75-0.8e20 m-2. First H-mode
is between ELMfree and EDA. Prf=2.5 MW. H/D=10-12%

Next shot: no PCS changes.

We are now doing between-shot ECDC in D2 for 8 minutes.

Shot 24 -- Plasma. Good shot. Target nl_04=0.8e20 m-2. All the H-modes are
EDA. RF faulted very early.

Next shot: raise density to nl_04=0.9e20 m-2. No between-shot ECDC.

Shot 25 -- Fizzle! Fields and pressure look as good as on any other shot.

End of run

Session Leader Comments

Sep 14 2000 11:04:39:340AM 1000914002 Amanda Hubbard nel_01 5.2e19; only 1.1 MW RF. L-mode

Sep 14 2000 11:03:15:763AM 1000914003 Amanda Hubbard
Late H-mode 1.2 sec; took 2.1 MW power. nel-01 0.6e19m-2.

Brief ELM-free period, evolving to EDA. Too late for fluctuation data.
Need to raise RF power earlier.

Sep 14 2000 11:01:02:327AM 1000914004 Amanda Hubbard
H-mode; took 2.6 MW power. nel-01 0.8-1.6e19m-2.

Brief ELM-free period, evolving to EDA. Confirmed by fluctuation data.
Need to reduce ne some more

Sep 14 2000 10:31:37:577AM 1000914005 Amanda Hubbard Dropped density to nel_1 ~6e19m-2. Got very late H-mode; it took 2.8 MW!

Looks like it starts ELM-free, with periods of ELMs or EDA. Too late for fluctuation data.

Sep 14 2000 10:49:09:983AM 1000914006 Amanda Hubbard
Despite Bob's rude comments, this shot did what I hoped.

A series of several ELM-free H-mode was followed by one with EDA (and higher starting nel~8e19).
This was confirmed by very clear fluctuation signals on the PCI and reflectometer.

Radiation, however, went up fast in ELM-free, eroding the pedestals.

Repeat this one.

Sep 15 2000 02:45:37:840PM 1000914007 Amanda Hubbard Lower RF power; L-mode

Sep 14 2000 11:25:13:513AM 1000914008 Amanda Hubbard Starting density is down to 3e19m-3. H-modes are getting very unclear; hardly any density response,
and just a brief Te rise.

Still core Te's up to 4keV!

For next shots, start slowly raising density. nel 4e19 for shot 9

Sep 14 2000 11:55:36:733AM 1000914009 Amanda Hubbard Starting density 4e19m-3.
UP TO 5keV early in shot. RF still doing nicely, ~ 3 MW.

A number of H-modes, but very short, not clear on type.

Early ones have te8 to 800 eV, little ne rise.

Later ones have ne rise, but modest Tedge.

Sep 15 2000 02:46:46:873PM 1000914010 Amanda Hubbard Starting density 5e19m-3.

Got a nice, longer ELM-free H-mode early (0.61 -0.68 seconds).
Impressive pedestal. Te8 to 900 eV. Te0 to 4.8 keV. There is some saturation on MIchelson and GPC Ch 2;
has probably been there a few shots.

Repeat, moving various fluctuation diagnostics earlier to look for any ELMs (none apparent)

Sep 15 2000 02:48:42:013PM 1000914011 Amanda Hubbard Repeat shot 10, increasing power earlier to move H-mode earlier.

Similar ELM-free H-mode, with NO edge fluctuations on PCI or reflectometer.

Sep 14 2000 01:03:10:810PM 1000914012 Amanda Hubbard Starting density 6e19m-3.

Series of decent H-modes. Ist ELM-free, just a hint of fluctuations late
2nd slight D-alpha rise, weak fluctn appears
3rd more EDA.

All appears to confirm role of target density in fluctns as well as Dalpha.

Sep 14 2000 03:32:02:793PM 1000914013 Amanda Hubbard Starting density 7e19m-3. Still nice steady RF.

Series of decent H-modes. All are now EDA, based on both D-alpha and PCI fluctuation,
which is MUCH stronger than on shot 6. Looks like we've found our EDA threshold!
Particle transport

Next shot; back to target 6e19 m-3 ramping RF power,

Sep 14 2000 03:47:32:500PM 1000914014 Amanda Hubbard Back to starting density 6e19m-3. RF power ramped. Threshold 1.8 MW; still high.

2 H-modes. The first shows a hint of fluctuations on PCI, mainly ELM-free. 2nd EDA

Sep 14 2000 03:48:39:437PM 1000914015 Amanda Hubbard Back to starting density 6e19m-3. RF power reduced to 2 MW.

Not very different from higher power; a weak hint of EDA fluctuations, a bit higher D-alpha.

Next shot: target 8e19, power ramped.

Sep 14 2000 03:49:40:873PM 1000914016 Amanda Hubbard Starting density 8e19m-3. RF power ramped 1-2.8 MW, as requested,

Two H-modes, both EDA but the second is much steadier. Interestingly, PCI shows fluctuations
are weaker in the first, and only start after a delay. The second, steadier EDA has much stronger
fluctuations; seems to be a quantitative correlation with particle transport.

The bad news is energy transport is also dropping; only H~1.3 vs 2.5 early in day.

Sep 14 2000 03:52:04:733PM 1000914017 Amanda Hubbard Starting density 9e19m-3. RF power ramped 1-2.8 MW, as requested,

One long, quite steady EDA.

Sep 14 2000 03:52:52:187PM 1000914018 Amanda Hubbard Starting density 1.1e19m-3. RF power lower; L-mode.

Sep 14 2000 03:51:26:340PM 1000914019 Amanda Hubbard Target 1.1e19. Ramped RF, steady EDA.

This finished 800 kA density scan.

Now go to 1 MA, low density.

Sep 14 2000 03:50:50:903PM 1000914020 Amanda Hubbard 1 MA. Target 6e19m-2.

Ramped RF. Nice series of H-modes. 1st is ELM-free, no PCI fluctuation.
2nd is EDA, clear fluctuation.

Next shot: same density, steady RF.

Sep 14 2000 04:12:31:780PM 1000914021 Amanda Hubbard Target still 6e19 m-2; actual a bit higher?

Level 2.6 MW; some trips late.
2 H-modes, type not so clear. ELM-free or weak eda??

Lower target for next shot.

Sep 14 2000 04:14:34:607PM 1000914022 Amanda Hubbard Target 5e19. 2 H-modes. 1st definitely ELM-free. No fluctuations, Te8 840 eV, 180 kJ

Later Weak EDA (late fluctns); Teped 413 eV, 114 kJ. Much lower confinement in EDA, all day.

Sep 14 2000 04:34:49:670PM 1000914023 Amanda Hubbard Target 7e19. 4 H-modes. 1st still looks fairly ELM-free; possibly weak EDA
Te8 730 eV, 173 kJ

Later EDA H-modes; Teped 385 eV, 132 kJ.

Sep 14 2000 05:45:17:670PM 1000914024 Amanda Hubbard Target 7e19. Did between shot ECDC. H-mode Looks a bit more EDAish, but still weak.

RF trips early,.

Physics Operator Comments

Sep 13 2000 06:18:21:733PM Robert Granetz Engineering setup for Thursday, 14 September 2000:

Overnight ECDC in HELIUM, stopping 1-2 hours prior to the run.

Run begins at 9:00 and ends at 17:00.

Power system setup as on 1000913002.

Gas setup - fill B-top with 6 psi of D2 Hybrid enabled
fill B-side lower with 1 psi of Ar Hybrid enabled
fill B-side upper with 35 psi of He Hybrid DISABLED (Yes, HELIUM)
(available for between-shot ECDC)
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 will be DISABLED for the beginning of the run; may enable later.

Sep 13 2000 06:18:54:107PM Robert Granetz Run plan for Thursday, 14 September 2000:

MP 278 -- ELMs and EDA in low density H-modes

Session leader: Amanda Hubbard
Physics operator: R. Granetz

Goals:

Clarify the role of density on the EDA/ELM-free boundary.

Investigate the ELMs previously observed in low density operation.

Shot sequence:

1) Start at 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. RF ramped to 1.5 MW. ELM-free
H-mode is anticipated at this low density. If it's EDA instead, then lower
density some more.

2) Increase Prf, shot-to-shot. Look for ELMs and trends in grad-P (5 shots)

3) Slowly increase nl_04 to 1e20 m-2. Monitor EDA signatures, especially
fluctuations. At each density, use 1 slow Prf ramp (to give L-H threshold
and time evolution) and 1-2 shots with higher, fixed Prf to maximize grad-P
and chance of triggering ELMs.

Anticipate 5 densities, 2-3 shots each (15 shots)

4) If time permits, raise Ip to 1 MA (where EDA is more marginal) and repeat
part of density scan to see if there is a "fixed" density limit or if there
is an interdependence of q and ne.

Sep 14 2000 08:28:28:000AM Robert Granetz Overnight ECDC in He

Hybrid coldstart done; no errors found

Loaded shot 1000913005 (segment 1 from 1000913016) and reduced Ip to
0.8 MA and nl_04 to 0.5e20 m-2. Remove waggle in Btor. Add 2 ms to
pre-fill puff.

Sep 14 2000 09:08:19:560AM 1000914001 Robert Granetz Shot 01 -- Fizzle. Pre-fill pressure was too low (due to He ECDC). Main video
cameras have no synch signal. Jim Terry needs cell access to fix.

Next shot: add 5 ms to pre-fill puff.

Sep 14 2000 09:36:17:717AM 1000914002 Robert Granetz Shot 02 -- Plasma. Good shot. Ip=0.8 MA, Bt=5.4 T, nl_04=0.5e20 m-2, as
requested. RF ramped, but started faulting around 1 MW. There
was some heating, but no H-mode.

Next shot: lower Br0 by 0.5 mT and increase IC_EF4 by +10 amps.
Try for a little higher RF power.

Sep 14 2000 09:49:18:543AM 1000914003 Robert Granetz Shot 03 -- Plasma. Good shot. nl_04=5.5-6e20 m-2. Got an H-mode which
briefly started as ELMfree before changing to EDA. Prf ramped
up to 2.0 MW and then leveled off. Pthreshold=2 MW. Strike point
is almost on the floor.

Next shot: raise ZXL by 5 mm. Ramp RF to 2 MW earlier in the shot.

Sep 14 2000 10:11:39:500AM 1000914004 Robert Granetz Shot 04 -- Plasma. Good shot. nl_04=0.7e20 m-2. The increase in the density
is coming from the RF. EDA H-mode (starting briefly as ELMfree).

Next shot: lower target density to nl_04=0.3e20 m-2 and lower the
pre-programmed valve voltage also.

Sep 14 2000 10:22:31:670AM 1000914005 Robert Granetz Shot 05 -- Plasma. Good shot. nl_04=3-4e19 m-2 target, rising to 6e19 m-2
during the RF just before H-mode. Prf ramps from 1.5 to 2.8 MW.
Got a short H-mode at the highest power. H/D is noisy (because
of the low signals), and varies up to 12%

Next shot: take 1 ms off pre-fill puff. Turn RF power on high
right from the start.

Sep 14 2000 10:55:36:060AM 1000914006 Robert Granetz Shot 06 -- Plasma. Good shot. Target nl_04=3e19 m-2. These have to be the
weirdest H-modes I've ever seen. Core x-ray brightness is
saturating at 150 kW/m2 (Peak xray emissivity about 1.5-2 MW/m3 !!)
Amanda likes this. Prf=2.6-2.9 MW. H/D=10% There's a small
glowing spot showing up on the inboard wall midplane at J or K.
My guess is it's a broken tile.

Next shot: enable DNB gate valve. DNB will fire after t=1.4 s.
Add 0.3 mT to Br0.

Sep 14 2000 11:02:59:153AM 1000914007 Robert Granetz Shot 07 -- Plasma. Good shot. Only one transmitter fired. No H-modes.
nl_04=3-3.5e19 m-2.

Next shot: Try RF again. Decrease pre-fill by 1 ms again, increase
IC_EF4 by +5 amps.

Sep 14 2000 11:32:20:090AM 1000914008 Robert Granetz Shot 08 -- Plasma. Disrupted at t=1.25 s. I think it's due to an injection
at t=1.24 s. Target nl_04=2.9e19 m-2. Prf=2.8 MW.

Next shot: increase nl_04 to 4e19 m-2. Decrease pre-fill by another
1 ms.

Sep 14 2000 12:13:03:687PM 1000914010 Robert Granetz Shot 10 -- Plasma. Good shot. Target nl_04=5e19 m-2. First H-mode was a nice
ELMfree one. Prf=2.8 MW.

Next shot: repeat, and set up some fast windows on magnetics,
PCI, reflectometer, and xtomo starting at t=0.6 s.

Sep 14 2000 12:41:30:543PM 1000914011 Robert Granetz Shot 11 -- Plasma. Good shot. Looks like a repeat of the previous shot.
First H-mode is ELMfree.

Next shot: increase target nl_04 to 6e19 m-2.

Sep 14 2000 12:58:36:373PM 1000914012 Robert Granetz Shot 12 -- Plasma. Good shot. Some ELMfree H-modes, some EDA H-modes.
H/D=8-12%. Prf=2.7 MW.

Next shot: increase target density to nl_04=0.7e20 m-2.

Sep 14 2000 01:13:38:280PM 1000914013 Robert Granetz Shot 13 -- Plasma. Good shot. Looks like all EDA H-modes, as Amanda
anticipated.

Next shot: decrease target density back to nl_04=0.6e20 m-2 (as
on shot 12) and look for ELMfree H-mode to reappear.

Sep 14 2000 01:30:02:420PM 1000914014 Robert Granetz Shot 14 -- Plasma. Good shot. Might be an ELMfree H-mode on this one.
RF was ramped from 1.0 to 2.8 MW. Target nl_04=0.6e20 m-2.

Next shot: set Prf to 2 MW (steady)

Sep 14 2000 01:58:38:450PM 1000914015 Robert Granetz Shot 15 -- Plasma. Good shot. Prf=2.0 MW from t=0.55 to 1.40 s. H/D=10-11%.

Next shot: Raise target density to nl_04=0.8e20 m-2. Also, ramp the
RF up to 2.8 MW.

Sep 14 2000 02:02:15:513PM 1000914016 Robert Granetz Shot 16 -- Plasma. Good shot. Prf ramps from 1.0 to 2.8 MW.

Next shot: Raise target density to nl_04=0.9e20 m-2.

Sep 14 2000 02:25:06:310PM 1000914017 Robert Granetz Shot 17 -- Plasma. Good shot. One long EDA H-mode. There was an injection
at t=1.2 s which degrades things somewhat.

The bright spot on the inboard wall has not been seen since we
started raising the density several shots ago. Chris Boswell has
magnified the CCD image and has determined that the bright spot
spanned parts of two tiles, and therefore it's probably not a broken
tile. Chris also noticed that the K-port midplane limiter was
getting very bright, so he's convinced me that the bright spot on
the inboard wall was actually a specular reflection of a hot spot
on the K-port midplane limiter. At the higher densities, the
limiter is not being heated as much.

Next shot: raise target density to nl_04=1.1e20 m-2

Sep 14 2000 02:47:12:153PM 1000914018 Robert Granetz Shot 18 -- Plasma. Good shot. No H-modes. Only had E-port transmitter,
Prf <= 1.0 MW. Target nl_04=1.0e20 m-2.

Next shot: repeat with both RF transmitters.

Sep 14 2000 03:05:13:217PM 1000914019 Robert Granetz Shot 19 -- Plasma. Good shot. One long steady EDA H-mode. H/D=9%.
Prf ramped up to 2.5 MW.

Next shot: increase Ip to 1.0 MA and decrease nl_04 to 0.6e20 m-2.

Sep 14 2000 03:23:30:357PM 1000914020 Robert Granetz Shot 20 -- Plasma. Good shot. Ip=1.0 MA. Target nl_04=6.7e19 m-2. First
H-mode looks ELMfree. Prf ramps from 1.0 to 2.3 MW. The ELMfree
H-mode occurs much earlier in the RF ramp, so it's obvious that
the higher current gets H-mode at a lower power threshold.

Next shot: no PCS changes. Tune RF.

Sep 14 2000 03:43:24:840PM 1000914021 Robert Granetz Shot 21 -- Plasma. Good shot. Prf=2.6 MW, but it faulted early. 2 H-modes.
H/D=10%.

Next shot: decrease nl_04 to 0.5e20 m-2. Also add -5 amps to
IC_EF4.

Sep 14 2000 04:03:25:233PM 1000914022 Robert Granetz Shot 22 -- Plasma. Good shot. First H-mode is ELMfree. Prf=2.6 MW.
H/D=10-12%, but it's noisy.

Next shot: raise nl_04 to 0.7e20 m-2.

Sep 14 2000 04:26:44:903PM 1000914023 Robert Granetz Shot 23 -- Plasma. Good shot. Target nl_04=0.75-0.8e20 m-2. First H-mode
is between ELMfree and EDA. Prf=2.5 MW. H/D=10-12%

Next shot: no PCS changes.

We are now doing between-shot ECDC in D2 for 8 minutes.

Sep 14 2000 05:21:17:200PM 1000914025 Robert Granetz Shot 25 -- Fizzle! Fields and pressure look as good as on any other shot.

End of run

Engineering Operator Comments

Shot Time Type Status Comment

1 08:59:42:670AM Plasma Ok

2 09:13:17:873AM Plasma Ok

3 09:34:39:327AM Plasma Ok

4 09:49:41:217AM Plasma Ok

5 10:08:13:763AM Plasma Ok

6 10:24:09:373AM Plasma Ok

7 10:53:36:000AM Plasma Ok

8 11:07:58:403AM Plasma Ok

9 11:31:51:013AM Plasma Ok

10 11:53:09:763AM Plasma Ok

11 12:23:49:920PM Plasma Ok

12 12:39:34:890PM Plasma Ok

13 01:00:03:687PM Plasma Ok

14 01:16:56:263PM Plasma Ok

15 01:35:57:500PM Plasma Ok

16 01:53:00:327PM Plasma Ok

17 02:13:05:200PM Plasma Ok

18 02:32:58:793PM Plasma Ok

19 02:51:07:920PM Plasma Ok

20 03:12:41:483PM Plasma Ok

21 03:32:14:140PM Plasma Ok

22 03:52:39:280PM Plasma Ok

23 04:12:36:687PM Plasma Ok

24 04:34:19:513PM Plasma Ok

25 04:54:27:280PM Plasma Ok

Session Leader Comments
Sep 14 2000 11:04:39:340AM	1000914002	Amanda Hubbard	nel_01 5.2e19; only 1.1 MW RF. L-mode
Sep 14 2000 11:03:15:763AM	1000914003	Amanda Hubbard	Late H-mode 1.2 sec; took 2.1 MW power. nel-01 0.6e19m-2. Brief ELM-free period, evolving to EDA. Too late for fluctuation data. Need to raise RF power earlier.
Sep 14 2000 11:01:02:327AM	1000914004	Amanda Hubbard	H-mode; took 2.6 MW power. nel-01 0.8-1.6e19m-2. Brief ELM-free period, evolving to EDA. Confirmed by fluctuation data. Need to reduce ne some more
Sep 14 2000 10:31:37:577AM	1000914005	Amanda Hubbard	Dropped density to nel_1 ~6e19m-2. Got very late H-mode; it took 2.8 MW! Looks like it starts ELM-free, with periods of ELMs or EDA. Too late for fluctuation data.
Sep 14 2000 10:49:09:983AM	1000914006	Amanda Hubbard	Despite Bob's rude comments, this shot did what I hoped. A series of several ELM-free H-mode was followed by one with EDA (and higher starting nel~8e19). This was confirmed by very clear fluctuation signals on the PCI and reflectometer. Radiation, however, went up fast in ELM-free, eroding the pedestals. Repeat this one.
Sep 15 2000 02:45:37:840PM	1000914007	Amanda Hubbard	Lower RF power; L-mode
Sep 14 2000 11:25:13:513AM	1000914008	Amanda Hubbard	Starting density is down to 3e19m-3. H-modes are getting very unclear; hardly any density response, and just a brief Te rise. Still core Te's up to 4keV! For next shots, start slowly raising density. nel 4e19 for shot 9
Sep 14 2000 11:55:36:733AM	1000914009	Amanda Hubbard	Starting density 4e19m-3. UP TO 5keV early in shot. RF still doing nicely, ~ 3 MW. A number of H-modes, but very short, not clear on type. Early ones have te8 to 800 eV, little ne rise. Later ones have ne rise, but modest Tedge.
Sep 15 2000 02:46:46:873PM	1000914010	Amanda Hubbard	Starting density 5e19m-3. Got a nice, longer ELM-free H-mode early (0.61 -0.68 seconds). Impressive pedestal. Te8 to 900 eV. Te0 to 4.8 keV. There is some saturation on MIchelson and GPC Ch 2; has probably been there a few shots. Repeat, moving various fluctuation diagnostics earlier to look for any ELMs (none apparent)
Sep 15 2000 02:48:42:013PM	1000914011	Amanda Hubbard	Repeat shot 10, increasing power earlier to move H-mode earlier. Similar ELM-free H-mode, with NO edge fluctuations on PCI or reflectometer.
Sep 14 2000 01:03:10:810PM	1000914012	Amanda Hubbard	Starting density 6e19m-3. Series of decent H-modes. Ist ELM-free, just a hint of fluctuations late 2nd slight D-alpha rise, weak fluctn appears 3rd more EDA. All appears to confirm role of target density in fluctns as well as Dalpha.
Sep 14 2000 03:32:02:793PM	1000914013	Amanda Hubbard	Starting density 7e19m-3. Still nice steady RF. Series of decent H-modes. All are now EDA, based on both D-alpha and PCI fluctuation, which is MUCH stronger than on shot 6. Looks like we've found our EDA threshold! Particle transport Next shot; back to target 6e19 m-3 ramping RF power,
Sep 14 2000 03:47:32:500PM	1000914014	Amanda Hubbard	Back to starting density 6e19m-3. RF power ramped. Threshold 1.8 MW; still high. 2 H-modes. The first shows a hint of fluctuations on PCI, mainly ELM-free. 2nd EDA
Sep 14 2000 03:48:39:437PM	1000914015	Amanda Hubbard	Back to starting density 6e19m-3. RF power reduced to 2 MW. Not very different from higher power; a weak hint of EDA fluctuations, a bit higher D-alpha. Next shot: target 8e19, power ramped.
Sep 14 2000 03:49:40:873PM	1000914016	Amanda Hubbard	Starting density 8e19m-3. RF power ramped 1-2.8 MW, as requested, Two H-modes, both EDA but the second is much steadier. Interestingly, PCI shows fluctuations are weaker in the first, and only start after a delay. The second, steadier EDA has much stronger fluctuations; seems to be a quantitative correlation with particle transport. The bad news is energy transport is also dropping; only H~1.3 vs 2.5 early in day.
Sep 14 2000 03:52:04:733PM	1000914017	Amanda Hubbard	Starting density 9e19m-3. RF power ramped 1-2.8 MW, as requested, One long, quite steady EDA.
Sep 14 2000 03:52:52:187PM	1000914018	Amanda Hubbard	Starting density 1.1e19m-3. RF power lower; L-mode.
Sep 14 2000 03:51:26:340PM	1000914019	Amanda Hubbard	Target 1.1e19. Ramped RF, steady EDA. This finished 800 kA density scan. Now go to 1 MA, low density.
Sep 14 2000 03:50:50:903PM	1000914020	Amanda Hubbard	1 MA. Target 6e19m-2. Ramped RF. Nice series of H-modes. 1st is ELM-free, no PCI fluctuation. 2nd is EDA, clear fluctuation. Next shot: same density, steady RF.
Sep 14 2000 04:12:31:780PM	1000914021	Amanda Hubbard	Target still 6e19 m-2; actual a bit higher? Level 2.6 MW; some trips late. 2 H-modes, type not so clear. ELM-free or weak eda?? Lower target for next shot.
Sep 14 2000 04:14:34:607PM	1000914022	Amanda Hubbard	Target 5e19. 2 H-modes. 1st definitely ELM-free. No fluctuations, Te8 840 eV, 180 kJ Later Weak EDA (late fluctns); Teped 413 eV, 114 kJ. Much lower confinement in EDA, all day.
Sep 14 2000 04:34:49:670PM	1000914023	Amanda Hubbard	Target 7e19. 4 H-modes. 1st still looks fairly ELM-free; possibly weak EDA Te8 730 eV, 173 kJ Later EDA H-modes; Teped 385 eV, 132 kJ.
Sep 14 2000 05:45:17:670PM	1000914024	Amanda Hubbard	Target 7e19. Did between shot ECDC. H-mode Looks a bit more EDAish, but still weak. RF trips early,.

Physics Operator Comments
Sep 13 2000 06:18:21:733PM		Robert Granetz	Engineering setup for Thursday, 14 September 2000: Overnight ECDC in HELIUM, stopping 1-2 hours prior to the run. Run begins at 9:00 and ends at 17:00. Power system setup as on 1000913002. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid enabled fill B-side upper with 35 psi of He Hybrid DISABLED (Yes, HELIUM) (available for between-shot ECDC) 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 will be DISABLED for the beginning of the run; may enable later.
Sep 13 2000 06:18:54:107PM		Robert Granetz	Run plan for Thursday, 14 September 2000: MP 278 -- ELMs and EDA in low density H-modes Session leader: Amanda Hubbard Physics operator: R. Granetz Goals: Clarify the role of density on the EDA/ELM-free boundary. Investigate the ELMs previously observed in low density operation. Shot sequence: 1) Start at 0.8 MA, 5.4 T, nl_04=0.5e20 m-2. RF ramped to 1.5 MW. ELM-free H-mode is anticipated at this low density. If it's EDA instead, then lower density some more. 2) Increase Prf, shot-to-shot. Look for ELMs and trends in grad-P (5 shots) 3) Slowly increase nl_04 to 1e20 m-2. Monitor EDA signatures, especially fluctuations. At each density, use 1 slow Prf ramp (to give L-H threshold and time evolution) and 1-2 shots with higher, fixed Prf to maximize grad-P and chance of triggering ELMs. Anticipate 5 densities, 2-3 shots each (15 shots) 4) If time permits, raise Ip to 1 MA (where EDA is more marginal) and repeat part of density scan to see if there is a "fixed" density limit or if there is an interdependence of q and ne.
Sep 14 2000 08:28:28:000AM		Robert Granetz	Overnight ECDC in He Hybrid coldstart done; no errors found Loaded shot 1000913005 (segment 1 from 1000913016) and reduced Ip to 0.8 MA and nl_04 to 0.5e20 m-2. Remove waggle in Btor. Add 2 ms to pre-fill puff.
Sep 14 2000 09:08:19:560AM	1000914001	Robert Granetz	Shot 01 -- Fizzle. Pre-fill pressure was too low (due to He ECDC). Main video cameras have no synch signal. Jim Terry needs cell access to fix. Next shot: add 5 ms to pre-fill puff.
Sep 14 2000 09:36:17:717AM	1000914002	Robert Granetz	Shot 02 -- Plasma. Good shot. Ip=0.8 MA, Bt=5.4 T, nl_04=0.5e20 m-2, as requested. RF ramped, but started faulting around 1 MW. There was some heating, but no H-mode. Next shot: lower Br0 by 0.5 mT and increase IC_EF4 by +10 amps. Try for a little higher RF power.
Sep 14 2000 09:49:18:543AM	1000914003	Robert Granetz	Shot 03 -- Plasma. Good shot. nl_04=5.5-6e20 m-2. Got an H-mode which briefly started as ELMfree before changing to EDA. Prf ramped up to 2.0 MW and then leveled off. Pthreshold=2 MW. Strike point is almost on the floor. Next shot: raise ZXL by 5 mm. Ramp RF to 2 MW earlier in the shot.
Sep 14 2000 10:11:39:500AM	1000914004	Robert Granetz	Shot 04 -- Plasma. Good shot. nl_04=0.7e20 m-2. The increase in the density is coming from the RF. EDA H-mode (starting briefly as ELMfree). Next shot: lower target density to nl_04=0.3e20 m-2 and lower the pre-programmed valve voltage also.
Sep 14 2000 10:22:31:670AM	1000914005	Robert Granetz	Shot 05 -- Plasma. Good shot. nl_04=3-4e19 m-2 target, rising to 6e19 m-2 during the RF just before H-mode. Prf ramps from 1.5 to 2.8 MW. Got a short H-mode at the highest power. H/D is noisy (because of the low signals), and varies up to 12% Next shot: take 1 ms off pre-fill puff. Turn RF power on high right from the start.
Sep 14 2000 10:55:36:060AM	1000914006	Robert Granetz	Shot 06 -- Plasma. Good shot. Target nl_04=3e19 m-2. These have to be the weirdest H-modes I've ever seen. Core x-ray brightness is saturating at 150 kW/m2 (Peak xray emissivity about 1.5-2 MW/m3 !!) Amanda likes this. Prf=2.6-2.9 MW. H/D=10% There's a small glowing spot showing up on the inboard wall midplane at J or K. My guess is it's a broken tile. Next shot: enable DNB gate valve. DNB will fire after t=1.4 s. Add 0.3 mT to Br0.
Sep 14 2000 11:02:59:153AM	1000914007	Robert Granetz	Shot 07 -- Plasma. Good shot. Only one transmitter fired. No H-modes. nl_04=3-3.5e19 m-2. Next shot: Try RF again. Decrease pre-fill by 1 ms again, increase IC_EF4 by +5 amps.
Sep 14 2000 11:32:20:090AM	1000914008	Robert Granetz	Shot 08 -- Plasma. Disrupted at t=1.25 s. I think it's due to an injection at t=1.24 s. Target nl_04=2.9e19 m-2. Prf=2.8 MW. Next shot: increase nl_04 to 4e19 m-2. Decrease pre-fill by another 1 ms.
Sep 14 2000 12:13:03:687PM	1000914010	Robert Granetz	Shot 10 -- Plasma. Good shot. Target nl_04=5e19 m-2. First H-mode was a nice ELMfree one. Prf=2.8 MW. Next shot: repeat, and set up some fast windows on magnetics, PCI, reflectometer, and xtomo starting at t=0.6 s.
Sep 14 2000 12:41:30:543PM	1000914011	Robert Granetz	Shot 11 -- Plasma. Good shot. Looks like a repeat of the previous shot. First H-mode is ELMfree. Next shot: increase target nl_04 to 6e19 m-2.
Sep 14 2000 12:58:36:373PM	1000914012	Robert Granetz	Shot 12 -- Plasma. Good shot. Some ELMfree H-modes, some EDA H-modes. H/D=8-12%. Prf=2.7 MW. Next shot: increase target density to nl_04=0.7e20 m-2.
Sep 14 2000 01:13:38:280PM	1000914013	Robert Granetz	Shot 13 -- Plasma. Good shot. Looks like all EDA H-modes, as Amanda anticipated. Next shot: decrease target density back to nl_04=0.6e20 m-2 (as on shot 12) and look for ELMfree H-mode to reappear.
Sep 14 2000 01:30:02:420PM	1000914014	Robert Granetz	Shot 14 -- Plasma. Good shot. Might be an ELMfree H-mode on this one. RF was ramped from 1.0 to 2.8 MW. Target nl_04=0.6e20 m-2. Next shot: set Prf to 2 MW (steady)
Sep 14 2000 01:58:38:450PM	1000914015	Robert Granetz	Shot 15 -- Plasma. Good shot. Prf=2.0 MW from t=0.55 to 1.40 s. H/D=10-11%. Next shot: Raise target density to nl_04=0.8e20 m-2. Also, ramp the RF up to 2.8 MW.
Sep 14 2000 02:02:15:513PM	1000914016	Robert Granetz	Shot 16 -- Plasma. Good shot. Prf ramps from 1.0 to 2.8 MW. Next shot: Raise target density to nl_04=0.9e20 m-2.
Sep 14 2000 02:25:06:310PM	1000914017	Robert Granetz	Shot 17 -- Plasma. Good shot. One long EDA H-mode. There was an injection at t=1.2 s which degrades things somewhat. The bright spot on the inboard wall has not been seen since we started raising the density several shots ago. Chris Boswell has magnified the CCD image and has determined that the bright spot spanned parts of two tiles, and therefore it's probably not a broken tile. Chris also noticed that the K-port midplane limiter was getting very bright, so he's convinced me that the bright spot on the inboard wall was actually a specular reflection of a hot spot on the K-port midplane limiter. At the higher densities, the limiter is not being heated as much. Next shot: raise target density to nl_04=1.1e20 m-2
Sep 14 2000 02:47:12:153PM	1000914018	Robert Granetz	Shot 18 -- Plasma. Good shot. No H-modes. Only had E-port transmitter, Prf <= 1.0 MW. Target nl_04=1.0e20 m-2. Next shot: repeat with both RF transmitters.
Sep 14 2000 03:05:13:217PM	1000914019	Robert Granetz	Shot 19 -- Plasma. Good shot. One long steady EDA H-mode. H/D=9%. Prf ramped up to 2.5 MW. Next shot: increase Ip to 1.0 MA and decrease nl_04 to 0.6e20 m-2.
Sep 14 2000 03:23:30:357PM	1000914020	Robert Granetz	Shot 20 -- Plasma. Good shot. Ip=1.0 MA. Target nl_04=6.7e19 m-2. First H-mode looks ELMfree. Prf ramps from 1.0 to 2.3 MW. The ELMfree H-mode occurs much earlier in the RF ramp, so it's obvious that the higher current gets H-mode at a lower power threshold. Next shot: no PCS changes. Tune RF.
Sep 14 2000 03:43:24:840PM	1000914021	Robert Granetz	Shot 21 -- Plasma. Good shot. Prf=2.6 MW, but it faulted early. 2 H-modes. H/D=10%. Next shot: decrease nl_04 to 0.5e20 m-2. Also add -5 amps to IC_EF4.
Sep 14 2000 04:03:25:233PM	1000914022	Robert Granetz	Shot 22 -- Plasma. Good shot. First H-mode is ELMfree. Prf=2.6 MW. H/D=10-12%, but it's noisy. Next shot: raise nl_04 to 0.7e20 m-2.
Sep 14 2000 04:26:44:903PM	1000914023	Robert Granetz	Shot 23 -- Plasma. Good shot. Target nl_04=0.75-0.8e20 m-2. First H-mode is between ELMfree and EDA. Prf=2.5 MW. H/D=10-12% Next shot: no PCS changes. We are now doing between-shot ECDC in D2 for 8 minutes.
Sep 14 2000 05:21:17:200PM	1000914025	Robert Granetz	Shot 25 -- Fizzle! Fields and pressure look as good as on any other shot. End of run

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:59:42:670AM	Plasma	Ok
2	09:13:17:873AM	Plasma	Ok
3	09:34:39:327AM	Plasma	Ok
4	09:49:41:217AM	Plasma	Ok
5	10:08:13:763AM	Plasma	Ok
6	10:24:09:373AM	Plasma	Ok
7	10:53:36:000AM	Plasma	Ok
8	11:07:58:403AM	Plasma	Ok
9	11:31:51:013AM	Plasma	Ok
10	11:53:09:763AM	Plasma	Ok
11	12:23:49:920PM	Plasma	Ok
12	12:39:34:890PM	Plasma	Ok
13	01:00:03:687PM	Plasma	Ok
14	01:16:56:263PM	Plasma	Ok
15	01:35:57:500PM	Plasma	Ok
16	01:53:00:327PM	Plasma	Ok
17	02:13:05:200PM	Plasma	Ok
18	02:32:58:793PM	Plasma	Ok
19	02:51:07:920PM	Plasma	Ok
20	03:12:41:483PM	Plasma	Ok
21	03:32:14:140PM	Plasma	Ok
22	03:52:39:280PM	Plasma	Ok
23	04:12:36:687PM	Plasma	Ok
24	04:34:19:513PM	Plasma	Ok
25	04:54:27:280PM	Plasma	Ok