Miniproposals

Miniproposal: 550 Date Filed: 4/15/2008 Title: Locked Mode Rotation Studies First Author: Alex Ince-Cushman Session Leader: Alex Ince-Cushman (shots 1-32)

Engineering Operator Run Comment

MP 550, Momentum transport w/A-coil locking/unlocking SL: Alex Ince-Cush

Session Leader Plans

Entered: May 19 2008 11:48:57:793AM

Author: Alex Ince-Cushman

MP 550: Locked Mode Rotation Studies Session Leader: Alex Ince-Cushman PhysOp: Bill Rowan The purpose of this experiment is to use locked modes as a means of perturbing the toroidal rotation profile to allow for momentum transport studies. A secondary goal involves investigating the relationship between the [dB/B] locked mode threshold and toroidal rotation velocity. Diagnostics: Hirex-sr, Hirex-jr, Thomson, Edge Thomson, ECE, Chromex, CXRS, MSE Step 1: Locked mode discharge (1-2 shots) -The first few shots will be used to reproduce the now standard Hirex-Sr calibration locked mode discharge (load shot 1080215001). Step 2: Locking/unlocking a high rotation discharge (10 shots) - Load shot 1080130025 - Keep the feedback on throughout the discharge but change the target error field from 0 to 5G and/or -5G (to lock) and then back to 0 G (to unlock). - If we are unable to get the discharge to lock, the density will be lowered to reduce the locking threshold. Step 3: Magnetic Topology Variation - SSEP will be reduced to maximize the rotation in the un-locked RF heated phase of the discharge (5 shots)

Physics Operators Plans

Entered: May 18 2008 06:09:01:360PM

Author: Bill Rowan

Purpose: MP 550, Momentum transport w/A-coil locking/unlocking SL: Alex Ince-Cushman PO: Bill Rowan ----------------- Engineering Setup ----------------- Run begins at 09:00 and ends at 17:00 Power systems as on: 1080215001 Acoil: +Dtop -Dbot -Jtop +Jbot (standard) Hybrid Enabled (PO note to self: double check acoil dpcs before run) Gas setup: Fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid DISABLED (PG1) leave B-side upper as is Hybrid DISABLED (PG2) fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3) fill NINJA with 10 psi D2 DISABLED Enable gatevalves and shutters: ECE, VUV, DNB, Z-bolo Torvac gatevalve toggle (yes/no): Boronization(yes/no): no Overnight ECDC (yes/no): yes ICRF(yes/no): yes LH(yes/no): no DNB(yes/no): yes Cryopump (yes/no): yes Vessel temperature: 35/35/35 ------------------------------ ECDC Parameters (if requested) ------------------------------ gas and pressure: D2 at 2e-4 Torr sweep: 44/45/103 cm scan: 20/120 s

Session Leader Summaries

Entered: May 20 2008 06:19:43:440PM

Author: Alex Ince-Cushman

MP 550: Locked mode rotation studies The fiducial locked mode portion of the experiment was successful. The first two shots of the day had steady locked modes, both of which started at ~0.7 s and persisted until the end of the discharges. A total of 32 shots were attempted, 9 of which were fizzles, duds, or early disruptions. Of the remaining 23 discharges, 20 were successfully locked. Only 3 of these 20 were â??unlockedâ?? (29, 30,31, with 31 being the trophy shot). A number of different A-coil programming approaches were tried, however, the only successful receipt was: - Begin with nl04 = 0.35e19m^2, Ip = 0.8 MA, Bt= 5.4T - Ramp the A-coils from 0 to 6G starting at 0.5s over 100ms (this induces a locked mode at about 0.8s) - Ramp the A-coils from 6G to 0 G at 1.0s over 100 ms - Ramp the density from 0.35 to 0.5 nl04 starting at 1.05s over 150 ms (this unlocks the plasma at about 1.25s) Shot 30, should provide a data set that will allow for momentum transport analysis. Also of note was the demonstrated ability to lock discharges at high rotation (up to 30km/s). Shot 26 is a particularly striking example of rotation inversion with density modification first observed on TCV. Two rotation inversions are seen in this discharge as the result of changes in density. This is the best data we have of this kind to date.

Physics Operator Summaries

Entered: May 21 2008 06:53:21:513AM

Author: Bill Rowan

Physics Operator Summary for 1080520 In this run, we sought a set of control parameters which would lock and then unlock MHD modes. This capability can be used as a tool for study of toroidal momentum transport. A-coil programming, plasma current, density, density ramping, and ICRF were varied in LSN and USN configurations with and without cryopumping. For shots 029 through 031, locking followed by unlocking was observed. During the run, locking was often observed, but unlocking events were very rare. Note that 031 and 032 were identical in control parameters but 031 was successful in that it locked and then unlocked. 032 locked but never unlocked. Disruptions were common but occurred usually during rampdown. This is not surprising since mode locking was common. A few disruptions occurred during the current plateau and were associated with locking or with injections. Score Card 30 plasmas 2 fizzles 32 total discharges

Session Leader Comments
May 20 2008 09:11:57:360AM	1080520001	Alex Ince-Cushman	Shot locked at ~0.7s and lasted until the shot disrupted at ~1.6s. Lower hybrid was inadvertently started at t = 0s.
May 20 2008 09:34:29:783AM	1080520002	Alex Ince-Cushman	Shot locked at ~0.65s and lasted until the shot disrupted at ~1.6s. Lower hybrid came on at 1.4s for 100ms.
May 20 2008 10:14:28:530AM	1080520005	Alex Ince-Cushman	The shot did not lock and disrupted at ~1.1s. For the next shot, we will back off on the Ar puff and reduce the density to nl04~5e19 from ~6.5e19. There was a TCV like rotation inversion at ~0.75s associated with the changing density.

Physics Operator Comments
May 20 2008 07:46:30:700AM		Bill Rowan	Logged in as physop
May 20 2008 08:27:05:090AM		Bill Rowan	Loaded from 1080215001. Note segment 01 and 03 are on. Load a non-cryo startup from Friday. 1080516010. Selected this because it was near the end of the ITB run. The second exp on Friday may have used a special startup? Loaded dpcs
May 20 2008 08:29:41:950AM		Bill Rowan	Argon: on at 0.3 and off at 0.5
May 20 2008 08:32:29:047AM		Bill Rowan	b-side lower (PG1) enabled
May 20 2008 09:06:25:120AM	1080520001	Bill Rowan	001. Plasma Disrupted at 1.6 s LH turned on at t=0 Locked at 0.73 s as expected. Next shot. No DPCS changes LH moved to later in the shot.
May 20 2008 09:34:52:033AM	1080520002	Bill Rowan	002. Plasma Disrupted at 1.6 s Locked earlier; 0.65 LH at 1.4 s, x-rays on wide2 Engineering fault after the shot. EF1 Next shot SL requested that we go to Step 2 Loaded from 1080130025 Load segment 1 from 1080520002 Increase the prefill to 59 ms A-coils: 0.0005 T from 0.7 to 1.1
May 20 2008 09:49:07:513AM	1080520003	Bill Rowan	003. Disruption at 0.18 s May be an injection Next shot: no dpcs changes
May 20 2008 09:57:48:630AM	1080520004	Bill Rowan	004. Plasma Disruption at 1.6 s Did not lock. nl_04 = 0.84e+20 Next shot pellet at 1.5 s Lower nl_04 demand to 0.6
May 20 2008 10:12:56:793AM	1080520005	Bill Rowan	005. Plasma Disruption at 1.1 s nl_04 = 0.6e+20 Next shot. reduced the nl_04 demand to 0.5 reduced argon. now on: 0.3 , off: 0.7
May 20 2008 10:48:45:407AM	1080520007	Bill Rowan	007. Plasma Disruption at 1.5 s Next shot A-coil programming changed. Instead of going back to 0 go back to -0.0002
May 20 2008 11:03:41:357AM	1080520008	Bill Rowan	008. Plasma Disruption at 1.6 s nl_04=0.4e+20 Next shot. A-coil programming to -0.0004 at 1.2 s
May 20 2008 11:20:53:743AM	1080520009	Bill Rowan	009. Plasma Disruption at 1.5 s Next shot. A-coil programming to 0.0002 at 1.2 s Lengthened argon puff now 0.3 s to 1.2 s
May 20 2008 11:39:29:413AM	1080520010	Bill Rowan	010. Plamsa No locking. bolo indicates radiation increase when argon goes in there were a few spikes in bolo and soft x-ray which may indicate injections Next shot. Argon puff shortened 0.3 s to 0.7 s RF on at 1 s
May 20 2008 11:53:33:440AM	1080520011	Bill Rowan	011. Plasma Locks a 0.97 s Does not unlock Next shot. RF timing changed
May 20 2008 12:07:30:093PM	1080520012	Bill Rowan	012. Fizzle Ratiomatic was off. Next shot. Reduce prefill by 2 ms
May 20 2008 12:25:43:920PM	1080520013	Bill Rowan	013. Plasma Locked but no unlock Next shot A-coil programming to -0.0004 at 1.2 s
May 20 2008 12:30:08:780PM	1080520013	Bill Rowan	Added a second argon puff from 1.2 to 1.4
May 20 2008 12:52:57:877PM	1080520014	Bill Rowan	014. Plasma Locked at 0.95. did not unlock Next shot. Reload 1080520002 Turn off the preprogramed A-coil by 1.2 No cryo
May 20 2008 12:53:11:940PM	1080520015	Bill Rowan	015. Fizzle Next shot. As before (012), remove 2 ms of gas
May 20 2008 01:12:17:470PM	1080520016	Bill Rowan	016. Plasma Disruption at 0.2 s; much like shot 003; before it diverted Also first shot after a change in configuration but had not yet diverted Injection Next shot. No PCS changes
May 20 2008 01:32:08:390PM	1080520017	Bill Rowan	017. Plasma Disruption at 1.5 s Locks at 0.6. Next shot. reload shot 014. reload segment 1 from 017 add a density ramp from 1.2 to 1.5 nl_04 from 0.4 to 0.6 reduced pg3
May 20 2008 01:42:38:963PM	1080520018	Bill Rowan	018. Plasma Disruption at 0.9 s First shot after a configuration change. Injection Next shot. No DPCS changes
May 20 2008 02:11:18:110PM	1080520020	Bill Rowan	020. Plasma Disruption at 1.0 s Next shot IP reduced to 0.8 MA
May 20 2008 02:18:31:583PM	1080520021	Bill Rowan	021. Fizzle CII about twice as large as previous shot Next shot. No dpcs changes
May 20 2008 02:34:20:157PM	1080520022	Bill Rowan	022. Plasma Disruption at 0.9 s Next shot. reduce the argon puff on: 0.3 s and off 0.5 s
May 20 2008 03:05:17:213PM	1080520024	Bill Rowan	024. Plasma Plasma into ramp down Next shot. A-coil programming changed. Peak is 6G and then it ramps down after 1 s to -4G at the end of the shot
May 20 2008 03:16:19:613PM	1080520025	Bill Rowan	025. Plasma Next shot. Density ramp 1.1 s to 1.3 s nl_04 from 0.4 to 0.6
May 20 2008 03:46:04:230PM	1080520027	Bill Rowan	027. Plasma Locks but does not unlock
May 20 2008 03:52:34:577PM	1080520027	Bill Rowan	027. Plasma Locks but does not unlock Next shot. Reduce max after nl_04 ramp from 0.6e+20 to 0.5e_20
May 20 2008 04:02:09:193PM	1080520028	Bill Rowan	028. Plasma Locks. Next shot. Change a-coil programming. Ramp down to 0
May 20 2008 04:30:13:153PM	1080520029	Bill Rowan	029. Plasma Locks and then unlocks just before the end of the flat-top Next shot. Change the A-coil rampdown Start at 1.1 and end at 0 at 1.2 s
May 20 2008 04:59:28:067PM	1080520031	Bill Rowan	031. Plasma Locked and unlocked Next shot.

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	08:58:20:100AM	Plasma	Ok
2	09:13:27:970AM	Plasma	Ok	EF1L fault low AC phase sequence
3	09:35:54:253AM	Plasma	Ok
4	09:49:52:390AM	Plasma	Ok
5	10:03:21:507AM	Plasma	Ok
6	10:18:48:300AM	Plasma	Ok
7	10:35:34:163AM	Plasma	Ok
8	10:51:11:580AM	Plasma	Ok
9	11:07:52:013AM	Plasma	Ok
10	11:26:05:547AM	Plasma	Ok
11	11:41:30:837AM	Plasma	Ok
12	11:59:54:510AM	Plasma	Ok
13	12:12:20:190PM	Plasma	Ok
14	12:31:04:657PM	Plasma	Ok
15	12:49:12:420PM	Plasma	Ok
16	01:02:07:557PM	Plasma	Ok
17	01:14:45:067PM	Plasma	Ok
18	01:33:12:720PM	Plasma	Ok
19	01:46:30:840PM	Plasma	Ok
20	02:01:48:350PM	Plasma	Ok
21	02:14:19:783PM	Plasma	Ok
22	02:27:07:107PM	Plasma	Ok
23	02:40:02:223PM	Plasma	Ok
24	02:53:41:547PM	Plasma	Ok
25	03:07:29:637PM	Plasma	Ok
26	03:20:46:897PM	Plasma	Ok
27	03:41:07:177PM	Plasma	Ok
28	03:57:30:393PM	Plasma	Ok
29	04:16:46:690PM	Plasma	Ok
30	04:37:17:067PM	Plasma	Ok
31	04:51:39:950PM	Plasma	Ok
32	05:07:00:400PM	Plasma	Ok

System Availability

May 20 2008 08:58:11:707AM

System Available Comment Availability Changed Owner Description Who Can Change Active MHD yes Fully operational Mar 28 2007 09:19PM (sears) Joe Snipes Active MHD Antenna sears,snipes BES yes vertical array of six views at R ~ 87.3 cm, radial array of three views out to R ~ 89 cm, both at outboard midplane. Three discrete fiber views of beam at R ~ 70.0, 76.5 and 82.5 cm. Feb 06 2007 10:00AM (bravenec) Ron Bravenec Beam Emission Spectroscopy bravenec,rowan Bolometers yes Diode 2pi working fine, foil 2pi being low-pass filtered to remove noise. Outboard miidplane AXUV has a grounded channel which is disrupting the whole array OFFLINE for now. Midplane foils working fine, but need to fill tree with calibrations. 2D AXUV arrays are being digitized but need further debugging and calibration. Mar 14 2008 11:09AM (mlreinke) Matt Reinke Bolometers hutch,mlreinke Boronization yes System Operational Apr 29 2008 03:29PM (irby) Jim Irby Boronization dekow,irby CNPA yes Single channel CNPA available as of 12/1707 Dec 17 2007 05:48PM (parker) Ron Parker Compact Neutral Analyzer parker Cryopump - Upper Divertor yes Cryopump is operational Dec 11 2007 10:13AM (labombard) Brian LaBombard Upper Divertor Cryopump irby,labombard CXRS yes The pedestal toroidal array was installed, spatially and absolutely calibrated. There are 10 chords intersect the beam at the major_R_range=[74.2:86.3]cm. Spatial resolution: 1.2 cm. The F-top poloidal array was installed and spatially calibrated. There are 19 chords intersect the beam at the major_R_range=[67.8:91.0]cm. Spatial resolution: 1.22 cm. Nov 27 2007 10:21AM (bespam) Bill Rowan Charge Exchange Spectroscopy bespam,blip,rachmcd,rowan D Alpha yes \ha2_bright and \SPECTROSCOPY::TOP.VUV.VIS_SIGNALS:MCP_VIS_SIG1 are available Nov 26 2007 04:23PM (terry) Jim Terry Balmer Alpha Monitor irby,terry,wolfe Dalsa yes optics repaired, camera re-installed, and view has been re-calibrated Nov 27 2007 09:54AM (marmar) Earl Marmar Visible Bremsstrahlung marmar Disruption Mitigation no   Nov 20 2007 10:47PM (granetz) Robert Granetz Gas Jet granetz,whyte Divertor IR no   Mar 06 2007 10:50AM  Glen Wurden Divertor IR Digital Video gwurden,terry Divertor IR Spectroscopy no   Mar 06 2007 10:51AM  Glen Wurden Divertor IR Spectroscopy gwurden,terry DNB no   Nov 20 2007 10:47PM (granetz) Robert Granetz Diagnostic Neutral Beam beals,granetz FRC-ECE yes 16 Channels now working - low freq. side - outer Rmids Feb 19 2008 09:56AM (phillips) Perry Phillips Heterodyne ECE-32 channels phillips G-Side Ratiomatic yes Gauge is operational and calibrated against G-side MKS on shot#1071127002 Nov 27 2007 01:25PM (labombard) Brian LaBombard G-side ratiomatic ionization gauge labombard,toland GPC yes All 9 channels operational as of new year. Jan 03 2008 09:31AM (hubbard) Amanda Hubbard ECE Polychromater hubbard,schmidt GPC2 yes Most channels operational. Jan 02 2008 12:22PM (hubbard) Amanda Hubbard ECE Polychromater hubbard,schmidt GPI no Neither the Xpt-view nor the midplane-view camera is operational. Nov 26 2007 04:25PM (terry) Jim Terry Gas Puff Imaging terry,zweben H/D yes Should be operational for the FY08 campaign Nov 27 2007 09:54AM (marmar) Earl Marmar H/D Ratio marmar Hirex Jr yes   Mar 06 2007 08:59AM (rice) John Rice High Resolution X-Ray ince,rice Hirex Sr no Be Window has a leak and so the gate valve is closed Nov 23 2007 12:50PM (ince) John Rice High Resolution X-Ray ince,rice HXR yes Something might be wrong with channel 26; all others working fine. Mar 23 2007 10:43AM (schmidt) Ron Parker Hard X-Ray Array parker,schmidt ICRF D-Antenna yes available (quarter-wave transformer for pre-matching) Dec 11 2007 09:01AM (ylin) Steve Wukitch D-port antenna wukitch,ylin ICRF E-Antenna yes available (with FFT for automatical matching) Dec 11 2007 09:01AM (ylin) Steve Wukitch E-port antenna wukitch,ylin ICRF J-Antenna yes normally in [0,pi,pi,0] phase for heating. current drive phase available if requested. Dec 11 2007 09:03AM (ylin) Steve Wukitch J-port antenna wukitch,ylin Lower Hybrid yes Body I Fault Circuits Repaired and tested. High power tests completed Dec 05 2007 06:40PM (dterry) Ron Parker Lower Hybrid dterry,parker LPI yes 1/9/08 Jan 09 2008 03:23PM (bose) Earl Marmar Lithium Pellet Injector bose,marmar Ly-alpha yes Midplane working fine, emissivity profiles being stored in tree, but still need to apply in-vessel calibrations to data. WB1-LY being digitized, but not processed in tree. Dec 09 2007 06:53PM (mlreinke) Matt Reinke Lyman alpha cameras labombard,mlreinke McPherson no Problems with detector. No quantitative line brightnesses possible. Qualitative tasks like impurity identification possible. Feb 15 2008 02:07PM (mlreinke) Jim Terry VUV Spectrometer mlreinke,terry Michelson yes Operational Apr 29 2008 02:30PM (hubbard) Amanda Hubbard ECE Te Profiles hubbard,schmidt MKS yes E-Top, E-Bottom, F-top (cryo), G-side, and B-bottom are operational. F-top gauge has a 'sniffer tube' to measure pressures in cryopump gas box. Mar 20 2007 06:42PM (g) Brian LaBombard Baratron pressure gauges labombard MLP no Initial tests on the A-port scanning probe went well. We need to take care of some control glitches that caused some component failures. May 30 2007 08:01PM (labombard) Brian LaBombard Mirror Langmuir Probe Electronics System labombard MSE no We are basically awaiting the DNB & its new aperture. MSE itself is OK. Feb 21 2008 08:51AM (jinseok) Steve Scott Motional Stark Effect jinseok,sscott Neutrons yes Voltage is on for the He3 bank. Voltage will be turned on for the global system at the first plasma attempts. Nov 26 2007 08:31AM (fiore) Catherine Fiore Neutron Detectors fiore Neuts and Hards yes calibration unchanged from 2007 campaign Dec 04 2007 08:56PM (irby) Jim Irby X-Ray/Neutron Detector at K-Hor irby NINJA yes All capillaries displayed by the NINJA_CONTROL GUI have been tested. Nov 26 2007 04:26PM (terry) Brian LaBombard NINJA gas puff labombard,terry PCI yes working Feb 29 2008 07:00PM (lianglin) Miklos Porkolab Phase Contrast Imaging edlund,lianglin,ntsujii,porkolab Penning Gauges yes All gauges except B_DivL are operating Nov 27 2007 01:31PM (labombard) Brian LaBombard Penning Ionization Gauges labombard Plasma TV yes WIDE1, WIDE2 (chan 33), DANT, JANT and DIV are operational. Nov 26 2007 04:27PM (terry) Jim Terry Video of plasma via several cameras dekow,irby,terry,wolfe Polarimeter no Safe for Machine Entry Sep 14 2007 12:17PM (irby) Jim Irby C-Mod Polarimeter irby Probe Array - ISD yes Operational Nov 27 2007 01:40PM (labombard) Brian Labombard Inner Lower Divertor Probe Array labombard Probe Array - LH yes Operational Nov 27 2007 01:40PM (labombard) Brian LaBombard Lower Hybrid Probe Array labombard Probe Array - OSD yes Operational Nov 27 2007 01:41PM (labombard) Brian LaBombard Outer Lower Divertor Probe Array labombard Probe Array - UDIV yes Operational Nov 27 2007 01:41PM (labombard) Brian LaBombard Upper Divertor Probe Array labombard Reflectometer yes System is fully connected except for the 75GHz channel. System was connected on 1080422. Apr 22 2008 08:26AM (dominguez) Earl Marmar Reflectometer dominguez,marmar Scanning Probe - ASP yes Operational, but needs to be checked with plasma. Nov 27 2007 01:45PM (labombard) Brian LaBombard A-Port Scanning Probe labombard Scanning Probe - FSP yes FSP is operational Dec 11 2007 10:13AM (labombard) Brian LaBombard F-Port Scanning Probe labombard Scanning Probe - WASP yes A- and K-port WASP electrodes have been replaced/tested. Nov 27 2007 01:44PM (labombard) Brian LaBombard Inner Wall Scanning Probe labombard,nsmick TCI yes Operational Apr 29 2008 03:33PM (irby) Jim Irby Two-Color Interferometer irby,murray TS - Core yes One laser operational, 12 spatial channels Apr 11 2008 10:36AM (jwhughes) Jerry Hughes Core Thomson scattering jwhughes,yma TS - Edge yes System is working with 3 out of 4 spectral channels and should be believable for Te>50eV, ne>3e19. Density is calibrated from both Raman scattering in D2 (3/2/08) and from edge ECE cutoffs in high-density H-modes (1080228014). Apr 11 2008 10:36AM (jwhughes) Jerry Hughes Millimeter resolution edge Thomson scattering jwhughes,yma Vispec no 350 and 670 nm, 4 spatial channels Nov 28 2007 09:58AM (agraf) Alex Graf Visible Spectrometer agraf XTOMO yes system operational, but channels have been dying...stay tuned. Mar 14 2008 11:10AM (mlreinke) Bob Granetz X-Ray Tomography granetz,mlreinke