Alcator C-Mod Run 1050826 Information

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Miniproposals
Miniproposal:409
Date Filed: 1/19/2005
Title:Phase Space of the Scrape-off-Layer Plasma
First Author:Brian Labombard
Session Leader:Brian Labombard (shots 1-27)

Operators
Session leader(s):Brian Labombard
Physics operator(s):Robert Granetz
Engineering operator(s):Bill Cochran,Bill Byford,Ed Fitzgerald

Engineering Operator Run Comment
automatically entered by signon - please replace with real comment

Session Leader Plans
Entered: Aug 25 2005 10:25:50:097PM
Author: Brian Labombard
Run Plan for 1050826

MP#409 "SOL Phase space studies"

Overall Goal
Map out the 'phase space' of the SOL plasma, i.e. the relationships between
the 'transport state' (profile shapes, gradients, cross-field fluxes, advection
velocities, turbulence characteristics) and theory-based 'control parameters'
(local collisionality, magnetic field strengths, parallel connection length,...)
that may determine that state.

Today's Goals
We will continue from the last time we attempted this MP (1050602), moving on to
Ip=0.4 MA, Bt=2.7 tesla. If things go well, we will collect some high density data at the nominal
Ip=0.8 MA, Bt=5.4 tesla values in lower single null - something we were not able
to do so far.

Run Preparation Tasks (for probe diagnostics)
- Reconfigure A14 and A12 digitizer connections to outer divertor probe
array according to file: "put_new_fast_refs_2005_mar01.tcl"
- Execute TCL>@put_new_fast_refs_2005_mar01.tcl
- Configure ASP bias supplies: PA93 amplifiers ("DC supply") in standard sweep mode,
"Sweep A" and "Sweep B" set to -200 volts
- Use IDL code to switch ASP probe triggering and ASP/FMP power supply biases
between one of two modes:
"Scan" mode - ASP: N,S,E,W electrodes in current mode, "DC supply"
Probe scanning three times during shot, 256k samples/channel
FMP: OSD**.p0 probes in current mode, "Sweep B" supply
OSD**.p1 probes in current mode, "DC -" supply
OSD**.p2 probes in floating mode, "DC +" supply
"Dwell" mode - ASP: W & S electrodes in current mode, "Sweep A" & "Sweep B"
N & E electrodes in floating mode
Probe in dwell mode, with 512k samples/channel
FMP: OSD**.p0 probes in current mode, "DC -" supply
OSD**.p1 probes in current mode, "DC -" supply
OSD**.p2 probes in floating mode, "DC +" supply
IDL code: mp409_scan.pro
undwell_scan_asp.pro
set_asp_pa93_sweep.pro
set_fmp_sweep.pro
mp409_dwell.pro
dwell_scan_asp.pro
set_asp_fluctuation_mp409.pro
set_fmp_fluctuation_mp409.pro

Run Preparation Tasks (for optical diagnostics)
- Set integration time on Xybion to 1 ms
- Connect the following fiber views for the fast diodes
Outer SOL views 1-3,5,7,9-14,31-40 (total of 21)
Innerwall SOL views B and C
- Connect the following fiber views for the CHROMEX
Outer SOL views 18-22,24-29 (total of 11)
Innerwall SOL views A,D,E,F - otherwise known as 1,4-6
- Set timing on fastdiode digitizers to 0.1 s after the A-B limiter NINJA puff timing


Plan
Start from shot#1050602032. This shot ran on segment#2. It was a LSN discharge
with Ip=0.4 MA, Bt ramping down to 2.7 tesla @ 0.95s, NL04 = 0.5e20. Note: segment#3 has
a USN program that we will use (Segment#4 is double-null? will not be used today.)
ASP, FSP, ISP programmed to scan at 0.65, 0.85, 1.05 seconds
NINJA gas puff for GPI and boron V spectroscopy entering plasma at 1.1s
Set NINJA for D2 puff at A-B limiter and B16-001. Plenum pressure of 10 PSI.

Shots

=> Ip=0.4 MA, Bt=2.7 tesla

1 LSN, NL04 = 0.5, Scan mode, optimize probe insertion
NINJA puff at 1.1 s, fast camera at 1.25 s
3 USN, NL04 = 0.5, Scan mode, optimize probe insertion
NINJA puff at 1.1 s, fast camera at 1.25 s

5 USN, NL04 = 0.4, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
7 LSN, NL04 = 0.4, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

9 LSN, NL04 = 0.3, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
11 USN, NL04 = 0.3, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

13 USN, NL04 = 0.2, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
15 LSN, NL04 = 0.2, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

17 LSN, NL04 = 0.6, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
19 USN, NL04 = 0.6, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

21 USN, NL04 = 0.7, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
23 LSN, NL04 = 0.7, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

Change to Ip=0.8 MA, Bt=5.4 tesla

25 LSN, NL04 = 1.2, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
27 USN, NL04 = 1.2, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
Note: If MARFES persist, then we will skip the USN discharges.

29 USN, NL04 = 1.4, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s
30 LSN, NL04 = 1.4, Scan mode
NINJA puff at 1.1 s, fast camera at 1.25 s

31 Fill NINJA plenum with 40 PSI D2
Set Xybion gain for NL04=2.4
Puff through B16-001 (inner midplane capillary) trigger=0.5s, duration=0.9s
(see shot#1021107016 as an example with 0.1s earlier trigger)
LSN, program NL04=1.0 - flat, get: NL04=1.4 to 2.7, from 0.7 to 1.2 s
Dwell mode,trigger=0.95 (dwell from 0.7 to 1.2s)

32 repeat 31: in Scan mode, with only ASP and ISP scanning at 0.8, 1.0, 1.2s
NL04 ~ 1.6, 2.2, 2.7

33 repeat 32: in Scan mode, with deep ASP scan at 1.2 s
NL04 ~2.7

Physics Operators Plans
Entered: Aug 25 2005 11:55:22:270AM
Author: Robert Granetz

Engineering setup for Friday 26 Aug 2005
 
MP #409: SOL Phase Space

Session leader: B. Labombard
Physics operator: R. Granetz
 
Overnight ECDC in HELIUM, and bake at 60 C.
 
Run begins at 09:00 and ends at 17:00.

Power systems as on 1050602032 (0.4 MA, 2.7 T, lower single null)

A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled.

Gas Setup:
   fill B-Top            with  6 psi D2  Hybrid enabled  (PG4)
   fill B-side lower     with  1 psi Ar + 2 psi Ne  Hybrid DISABLED (PG1)
  leave B-side upper     with whatever   Hybrid DISABLED (PG2)
   fill B-main (C-side)  with 40 psi D2  Hybrid enabled  (PG3)
   fill NINJA            with 10 psi D2  Leave DISABLED

Enable the following gate valves and shutters, assuming no vacuum problems:
  ECE, VUV, Z-bolo shutters
 
Torvac setup: Gate valves open

No between-shot boronization.

Important Diagnostics:
  ASP, FSP, ISP, Xybion camera, fast H-alpha diode array, Chromex, Edge TS

-------------------------------------------------------------------------------
ICRF Setup: No RF today.

-------------------------------------------------------------------------------
Run plan: See the session leader's detailed posting.

Session Leader Summaries
Entered: Aug 26 2005 09:40:58:520PM
Author: Brian Labombard
Run Summary for 1050826

MP#409 "SOL Phase space studies"
___________________________________________________________________________________
This run went fairly well despite a power-supply delay (about 1.2 hours for
OH2L commutation system) and a sprinkling of duds plus a fizzle. We got 19 discharges,
which we put to good use towards mining the low-density, low-field parameter space
of this MP. The focus today was on 0.4 MA, 2.7 T plasmas. A careful scan of density was
performed in matched upper and lower null topologies (NL04 from 0.2 to 0.5e20 m^-2).
We would have liked to additionally explore a higher range of densities (the MP called
for up to 0.7) but we just ran out of time.
Good profile and fluctuation data was obtained on high and low-field sides of the
SOL with probes, fast diodes (thanks to Olaf), and Chromex spectrometer (looking at
D-beta). We took special care to target the probes (ASP, FSP, ISP) at the seperatrix for
each set of conditions. The xybion camera was used to monitor D-alpha profiles on the
low-field side (thanks to Stewart for getting this working). The intention is to use
these data to infer ionization profiles in the SOL. Unfortunately, the image
of the fiber bundle on the camera had obviously moved and there were concerns of a boron
coating on the periscope window. To help sort some of this out, we re-ran a shot from
a previous run (1050304007) as the last two discharges today (shots 26 and 27). This
will allow us to compare the response of the xybion camera.
The data collected today should help us understand the role of that the
neutral ionization mean-free-path plays in affecting the SOL profiles, in particular
the appearance of a 'shoulder', which appears in the far SOL at moderate n/nG. Folded into
this story is the role that SOL flows might be playing. For example, we observed today that
the inner-wall probe persistently sees strong parallel plasma flows and a dependence on
upper/lower null topology over the full density range. Some interesting changes in flows
on the low field SOL (ASP) were also detected in the lowest density, upper single null
discharges. Plasma potential profiles as well as perpendicular Mach flows appear to be
affected. A comparison of shots 22, 24, and 25 revealed that these changes are linked
to upper versus lower-null topology. These data are also interesting in that they may
allow us to cross-check the perpendicular Mach flow measurement against an ExB flow as
inferred from plasma potential profile estimates. Stay tuned for further analysis.

Quick shot log:

Shots with Ip=0.4 MA, Bt=2.7 tesla

NL04=0.5 requested
01 - LSN, NL04=0.47, ASP(+0), FSP(-10), ISP(off) at 0.8, 1.0, 1.2 FSP 0.65, 0.85, 1.05- ASP
02 - LSN, NL04=0.5, ASP(+10), FSP(+10), ISP(14ms) at 0.8, 1.0, 1.2 - targeting a little deep
03 - LSN, NL04=0.5, ASP(+9), FSP(+9)-arcing on WEST, ISP(14ms) at 0.8, 1.0, 1.2 - targeting ok
04 - fizzle
05-07 power supply tests - 1.25 hour delay
08 - USN, NL04=0.48, ASP(+9), FSP(+9), ISP(14ms) at 0.8, 1.0, 1.2
09 - dud
10 - USN, NL04=0.5, ASP(+10), FSP(+9), ISP(14ms) at 0.8, 1.0, 1.2
11 - USN, NL04=0.49, ASP(+12), FSP(+9), ISP(14ms) at 0.8, 1.0, 1.2

NL04=0.4 requested
12 - USN, NL04=0.42, ASP(+12), FSP(+9), ISP(14ms) at 0.8, 1.0, 1.2 ISP hit by cross-over glitch
13 - USN, NL04=0.4 ASP(+13), FSP(+9)(West-floating), ISP(14ms) at 0.7, 0.9, 1.1 - excellent targeting
14 - LSN, NL04=0.44 ASP(+10), FSP(+7), ISP(14ms) at 0.7, 0.9, 1.1 - excellent targeting
15 - LSN, NL04=0.44 ASP(+10), FSP(+7), ISP(14ms) at 0.75, 0.95, 1.15

NL04=0.3 requested
16 - dud
17 - LSN, NL04=0.3 to 0.37 ASP(+10), FSP(+7), ISP(14ms) at 0.75, 0.95, 1.15
18 - dud
19 - LSN, NL04=0.3 to 0.32 ASP(+10), FSP(+7), ISP(14ms) at 0.75, 0.95, 1.15 - excellent targets
20 - USN, NL04=0.3 to 0.32, ASP(+13), FSP(+9), ISP(14ms) at 0.75, 0.95, 1.15 - excellent
21 - USN, NL04=0.3, ASP(+13), FSP(+9), ISP(14ms) at 0.75, 0.95, 1.15

NL04=0.2 requested
22 - USN, NL04=0.2, ASP(+13), FSP(+9), ISP(14ms) at 0.75, 0.95, 1.15 Positive Vf, different flows.
23 - dud
24 - LSN, NL04=0.2, ASP(+10), FSP(+7), ISP(14ms) at 0.75, 0.95, 1.15 Vf and flows back to 'normal'.
25 - USN, NL04=0.2, ASP(+13), FSP(+9), ISP(14ms) at 0.75, 0.95, 1.15 - again flows, Vf different like shot 22

Shots to make contact with earlier data having known Xybion calibration.
Reload from 1050304007
Ip=0.8 MA, Bt=5.4 tesla, NL04=0.67
26 - LSN, NL04=0.67, ASP(+2), FSP(+0), ISP(22ms) at 0.65, 0.85, 1.05 - FSP near sep., ASP far.
27 - LSN, NL04=0.67, ASP(+7), FSP(+0), ISP(22ms) at 0.65, 0.85, 1.05 - ASP, FSP at sep.

Physics Operator Summaries
Entered: Aug 26 2005 06:08:47:407PM
Author: Robert Granetz
Physics operator summary for Friday 12 Aug 2005:

MP #409 SOL Phase Space

Session leader: B. Labombard
Physics operator: R. Granetz
 
The tokamak ran reasonably well today, although we lost two hours in the
morning because of a problem with the commutation charging circuit for
OH2L.  It turns out that a cable connection had broken.  Once that was
fixed, the rest of the run went fairly well.  There were 4 true
duds/fizzles throughout the day, and I had to tweak the startup often.
We ran 0.4 MA, 2.7 T plasmas most of the day, switching between lower null
and upper null equilibria, and a range of lowish densities.  The last two
shots were at 0.8 MA and 5.4 T so that the session leader can touch base
with previous measurements.  See Brian's report for details on the probe
scan data.

Note: there were a number of resistance warnings on the OH2U coax (around
2.6-2.7 microohms).

Scorecard: 19 plasmas
            4 duds
            1 fizzle (commutation failure)
            1 power supply related abort
            2 power supply tests
           --------------
    Total: 27 shot cycles

Session Leader Comments
Aug 26 2005 09:22:59:527AM1050826001Brian LabombardShot 1 NL04=0.47 0.4 MA, 2.7T
ASP, FSP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.0s

Next: repeat
Aug 26 2005 09:44:38:310AM1050826002Brian LabombardShot 2 NL04=0.5 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - ok, a little deep
FSP - ok. a little deep, some arcing
ISP - ok

Next: repeat
Aug 26 2005 09:54:48:060AM1050826003Brian LabombardShot 3 NL04=0.5 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, arcing on WEST probe
ISP - ok

Next: go to USN
Aug 26 2005 01:02:54:000PM1050826008Brian LabombardShot 8 USN, NL04=0.48 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - could be deeper
FSP - ok, arcing on WEST probe
ISP - target pulls away

Next: repeat with flat inner wall gap at 13mm.
Aug 26 2005 01:28:03:203PM1050826010Brian LabombardShot 10 USN, NL04=0.5 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - target pulls away.
FSP - ok, arcing on WEST probe
ISP - target is great

Next: repeat with improved outer gap
Aug 26 2005 01:37:33:173PM1050826011Brian LabombardShot 11 USN, NL04=0.49 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - good
FSP - ok, arcing on WEST probe
ISP - target is great

Next: go to NL04=0.4
Aug 26 2005 01:53:22:203PM1050826012Brian LabombardShot 12 USN, NL04=0.42 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.8, 1.0, 1.2 s
NINJA trigger at 1.1s
ASP - good, could be deeper
FSP - ok, arcing on WEST probe
ISP - second scan got hit by cross-over glitch

Next: repeat
Aug 26 2005 02:06:02:297PM1050826013Brian LabombardShot 13 USN, NL04=0.4 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.7, 0.9, 1.1 s
NINJA trigger at 1.1s
ASP - excellent
FSP - ok, WEST probe is floating now
ISP - good

Next: go to LSN at NL04=0.4
Aug 26 2005 02:34:14:547PM1050826014Brian LabombardShot 14 LSN, NL04=0.44 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.7, 0.9, 1.1 s
NINJA trigger at 1.1s
ASP - excellent
FSP - ok, WEST probe is floating
ISP - gets close to cross-over glitch

Next: repeat
Aug 26 2005 02:34:05:780PM1050826015Brian LabombardShot 15 LSN, NL04=0.44 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - excellent
FSP - ok, WEST probe is floating
ISP - good

Next: go to NL04=0.3
Aug 26 2005 03:26:19:797PM1050826019Brian LabombardShot 19 LSN, NL04=0.3 to 0.32 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - good
FSP - ok, WEST floating
ISP - good

Next: go to USN at NL04=0.3
Aug 26 2005 03:43:32:110PM1050826020Brian LabombardShot 20 USN, NL04=0.3 to 0.32 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, WEST floating
ISP - ok

Next: repeat
Aug 26 2005 03:55:06:860PM1050826021Brian LabombardShot 21 USN, NL04=0.3 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, WEST floating
ISP - ok

Next: go to NL04=0.2
Aug 26 2005 04:31:52:547PM1050826022Brian LabombardShot 22 USN, NL04=0.2 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, WEST floating
ISP - ok
Plasma flows show and interesting change on this shot. M-perp stays negative
across the separatrix and the floating potentials become positive. This shot
may allow us to cross-check the M-perp measurements against ExB from
probe sheath potentials.

Next: go to LSN, NL04=0.2
Aug 26 2005 05:05:28:390PM1050826024Brian LabombardShot 24 LSN, NL04=0.2 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, WEST floating
ISP - ok
Plasma flows are back to 'normal' now. Apparently the key
knob is USN versus LSN

Next: go to back to USN, NL04=0.2
Aug 26 2005 05:07:00:907PM1050826025Brian LabombardShot 25 USN, NL04=0.2 0.4 MA, 2.7T
ASP, FSP, ISP scanning at 0.75, 0.95, 1.15 s
NINJA trigger at 1.1s
ASP - ok
FSP - ok, WEST floating
ISP - ok
Flows and floating potentials are again changed, similar to shot#22

Next: go to 0.8 MA, 5.4 T reference shot
Aug 26 2005 05:16:02:830PM1050826026Brian LabombardShot 26 LSN, NL04=0.66 0.8 MA, 5.4T
ASP, FSP, ISP scanning at 0.65, 0.85, 1.05 s
NINJA trigger at 1.1s
ASP - far from sep
FSP - ok, near sep. WEST floating
ISP - far from sep

Next: repeat with ASP inserted deeper.
Aug 26 2005 05:20:21:330PM1050826027Brian LabombardShot 27 LSN, NL04=0.66 0.8 MA, 5.4T
ASP, FSP, ISP scanning at 0.65, 0.85, 1.05 s
NINJA trigger at 1.1s
ASP - ok, second scan is best.
FSP - ok, near sep. WEST floating
ISP - far from sep

End of run

Physics Operator Comments
Aug 25 2005 06:47:43:830PMRobert GranetzLoaded shot 1050602032, then imported segment 1 from the last shot yesterday (1050825027).

Changed initial Btor in segment 2 to be 5.2 T instead of 5.4 T, just so that the field
ramps down to 2.7 T a little sooner. Also set Btor in segment 1 to 5.2 T.
Aug 26 2005 09:08:14:107AM1050826001Robert GranetzPlasma. Good shot. 0.4 MA, ramp down to 2.7 T, nl_04=0.5e20 m-2. But lots of runaways.
Startup bounced.

Next shot: increase pre-fill by 3 ms.
Aug 26 2005 09:36:33:450AM1050826002Robert GranetzPlasma. Good shot. 0.4 MA, 2.7 T, 0.5e20 m-2, LSN.
Got rid of the hard x-rays. Good startup.

Next shot: fire beam into tokamaks at t=0.15 s. Add 2 ms to pre-fill to compensate for DNB
pumpout.
Aug 26 2005 09:54:42:810AM1050826003Robert GranetzPlasma. Good shot. 0.4 MA, 2.7 T, 0.5e20 m-2, LSN.
DNB fired successfully into plasma. Good start.

Next shot: change to upper single null; keep all other parameters the same.
Aug 26 2005 10:08:52:560AM1050826004Robert GranetzFizzle. Fields look funny. OH2L did not commutate. Not sure about OH2U.

Next shot: try again, no DPCS changes.
Aug 26 2005 10:32:30:853AM1050826005Robert GranetzNo power. Pulse-forming-network (PFN) for the OH2L commutation again failed to work during check.
Aug 26 2005 10:53:00:010AM1050826006Robert GranetzTest of OH2L. Cap bank did NOT charge.
Aug 26 2005 11:13:32:920AM1050826006Robert GranetzThere will be an least an hour delay while the charging supply cable is fixed.
Aug 26 2005 12:29:30:220PM1050826007Robert GranetzTest of OH2 charging supply. Looks good.
Aug 26 2005 12:33:38:140PM1050826007Robert GranetzNext shot: go for plasma. Turn on DNB again.
Aug 26 2005 01:01:41:157PM1050826008Robert GranetzPlasma. Good shot. Upper single null. 0.4 MA, 2.7 T, 0.5e20 m-2. Outer gap ramps smaller by
6-8 mm over the flattop, but the scanning probe targeting is pretty good with this. Brian requests
tweaking inner gap so that it stays constant at 13 mm.

Next shot: tweak CLEARIN to keep inboard gap at 13 mm throughout flattop. Adjust RCUR for better
gap as well.
Aug 26 2005 01:25:44:703PM1050826009Robert GranetzDud. Everything looks good.

Next shot: shorten pre-fill by 2 ms.

Aug 26 2005 01:26:11:937PM1050826010Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.5e20 m-2.
Inboard gap is quite constant at 13 mm. Outer gap is better than it was, but
could still be improved a little more.

Next shot: reduce outer gap by 2 mm after t=0.9 s.
Aug 26 2005 01:35:05:703PM1050826011Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.5e20 m-2. Good gap control for the probes.

Next shot: USN, lower nl_04 to 0.4e20 m-2
Aug 26 2005 01:48:49:767PM1050826012Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.4e20 m-2.

Next shot: No DPCS changes. Brian will adjust timing of probe scans to avoid bad time
around PF zero-crossing.
Aug 26 2005 02:04:23:470PM1050826013Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.4e20 m-2.

Next shot: switch back to LSN (segment 2). Set nl_04 to 0.4e20 m-2. Tweak CLEARIN to keep
inboard gap constant at 13 mm.
Aug 26 2005 02:16:41:483PM1050826014Robert GranetzPlasma. Good shot. LSN, 0.4 MA, 2.7 T, 0.4e20 m-2.

Next shot: repeat, no DPCS changes
Aug 26 2005 02:28:29:983PM1050826015Robert GranetzPlasma. Good shot. LSN, 0.4 MA, 2.7 T, 0.4e20 m-2.

Next shot: LSN, set nl_04 to 0.3e20 m-2.
Aug 26 2005 02:43:47:423PM1050826016Robert GranetzDud. Everything looks good.

Next shot: raise Br0 by 0.0002 T and reduce pre-fill by 2 ms.
Aug 26 2005 02:52:44:877PM1050826017Robert GranetzPlasma. Good shot. LSN, 0.4 MA, 2.7 T, 0.3e20 m-2.
Startup bounced.

Next shot: add the 2 ms back to the pre-fill puff.
Aug 26 2005 03:04:35:877PM1050826018Robert GranetzDud.

Next shot: tweak IC_EF4, and add 1 ms to pre-fill
Aug 26 2005 03:22:13:580PM1050826019Robert GranetzPlasma. Good shot. LSN, 0.4 MA, 2.7 T, 0.3e20 m-2.
Startup still has a bounce and hard x-rays.

Next shot: upper single null, set nl_04 to 0.3e20 m-2. Also increase pre-fill another 1 ms.
Aug 26 2005 03:46:09:313PM1050826020Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.3e20 m-2.
Startup was better...no runaways.

Next shot: repeat, no DPCS changes.
Aug 26 2005 03:59:29:703PM1050826021Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.3e20 m-2.
Startup bounced...lots of hard x-rays.

Next shot: USN, reduce nl_04 to 0.2e20 m-2 (This will be the lowest value for today.)
Also add 1 ms to pre-fill puff.
Aug 26 2005 04:13:23:330PM1050826022Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.2e20 m-2.
Good startup.

Next shot: switch to LSN, set nl_04 to 0.2e20 m-2.
Aug 26 2005 04:19:57:813PM1050826023Robert GranetzDud.

Next shot: increase IC_EF4 (Bz0) by +10 amps.
Aug 26 2005 04:36:41:890PM1050826024Robert GranetzPlasma. Good shot. LSN, 0.4 MA, 2.7 T, 0.2e20 m-2.
Startup was okay.

Next shot: go back to USN at this density (shot 22)
Aug 26 2005 04:53:01:470PM1050826025Robert GranetzPlasma. Good shot. USN, 0.4 MA, 2.7 T, 0.2e20 m-2.
Okay startup.

Next shot: 0.8 MA, 5.4 T, SNL; load from shot 1050304007. Needed to zero the offsets in CLEARIN and
Ip. Imported segment 1 from most recent shot today. Changed Btor in segment 1 back to 5.4 T, rather
than 5.2 T.
Aug 26 2005 05:00:30:330PM1050826026Robert GranetzPlasma. Good shot. LSN, 0.8 MA, 5.4 T, 0.65e20 m-2.
Startup bounced...lots of hard x-rays.

Next shot: increase pre-fill puff another 2 ms. No other DPCS changes.
Aug 26 2005 05:44:24:250PM1050826027Robert GranetzPlasma. Good shot. LSN, 0.8 MA, 5.4 T, 0.6e20 m-2.
Good startup, no runaways.

End of run.

Engineering Operator Comments
ShotTimeTypeStatusComment
109:03:59:277AMPlasmaOk
209:26:10:450AMPlasmaOk
309:44:43:637AMPlasmaOk
410:01:05:073AMPlasmaOk
510:25:59:823AMPlasmaBadOH2L Cap Bank Problem
610:48:48:420AMPlasmaOk
712:27:45:983PMTestOkOH2U&L Capacitor charging test
812:42:15:360PMPlasmaOk
901:02:45:937PMPlasmaOk
1001:15:15:313PMPlasmaOk
1101:28:19:703PMPlasmaOk
1201:40:49:890PMPlasmaOk
1301:55:08:407PMPlasmaOk
1402:07:56:080PMPlasmaOk
1502:20:29:860PMPlasmaOk
1602:34:57:360PMPlasmaOk
1702:47:16:983PMPlasmaOk
1802:59:46:140PMPlasmaOk
1903:15:27:233PMPlasmaOk
2003:27:57:940PMPlasmaOk
2103:46:02:780PMPlasmaOk
2204:04:54:517PMPlasmaOk
2304:17:18:563PMPlasmaOk
2404:29:39:877PMPlasmaOk
2504:42:01:610PMPlasmaOk
2604:54:24:140PMPlasmaOk
2705:06:42:767PMPlasmaOk
2807:49:47:900AMTestOkShot cycle test