Transcript Summary of topic III: Plasma sources and diagnostics for

Summary of topic III:
-- Plasma sources and diagnostics for PMI facilities -Session contains 5 presentations ···
1. “High Flux Steady-State Plasma Source for Integrated PMI-PFC
Test Stand”
presented by Y. Raitses, PPPL
2. “Thermal regime of LaB6 cathode of plasma linear device”
presented by A. Ivanov (instead of V.I. Davydenko), Dudker Inst.
3. “Intense RF Plasma Source Research”
presented by R. Goulding, ORNL
4. “A collarborative Proposal to Explore on PSI-2 “Glow Discharge
Spectroscopy “ as an in vacuo PMIF Diagnostic"
presented by C.C. Klepper, ORNL
5. “Use of the focusing multi slit ion optical system at the diagnostic
neutral beam injectior RUDI”
presented by A. Listpad, Budker Inst.
Plasma
Source
Diagnostics
[1]
High Flux Steady-State Plasma
Source for Integrated PMI-PFC
Test Stand
Yevgeny Raitses, Stewart Zweben Robert
Goldston, Michael Jaworski and Randy
Wilson
PPPL, Princeton, New Jersey 08543, USA
PMI Workshop, Julich
19-21 September, 2011
Possible Source Options for Initial Phases of
Integrated PMI-PFC Test-Stand
• A steady-state currentless plasma flow of energetic
ions (~ 100 eV) to a floating plate
RF-Plasma + ICH/ECH heating, Plasma thrusters (Hall,
MPD, Arcjet, VASIMR)
GAMMA 10 E-div.
May be IDEAL or GDT or ZaP ?
• Non-ambipolar plasma flow to a biased target-plate
Arc plasma sources, RF-plasma sources (helicon, ICP),
DC-RF plasma sources
• Heat sources
Arc discharge, neutral and electron beams
Hall thruster (HT) can source highly ionized
currentless plasma flow in a broad energy range
Ne ~ 5 1018 m-3 in ionization region
Ion kinetic energy ~102-103 eV
Ion temperature ~ 1 eV
Current density ~103 -104 A/m2
Steady-state operation
12 cm diam. 2 kW PPPL HT
The use of Hall thruster for the small prototype teststand would make possible to study liquid lithium wall
with and without target bias
Summary
• There are no readily available plasma sources for the required PMI-PFC parameters:
1 MW power flux, 10-40 MW/m2 at 1 Tesla, Deuterium,  5 s
• High power source options which could be developed to match the proposed PMIPFC test stand requirements:
- GDT: could be the best way to go if it could operate  5 sec
- Helicon+ICH:  1 MW, high B-field (~ 1 Tesla) Deuterium operation need to be
demonstrated (Note: Ad Astra results: 200 kW at ~ 1-2 Tesla for Ar)
- Arc plasma sources (Magnum or MPD types): matches all requirements
including  10 MW/m2 (> 1MW power level is likely feasible)
Limitation: target-plate needs to be biased
Challenges: high background pressure ~ 10 mtorr
• Small scale PMI-PFC prototype test stand is proposed for internal PPPL support (not
funded yet):
The prototype test stand will be modular and may use variety of plasma
sources, including currentless (Hall thrusters) and non-ambipolar with biased
plate (RF-plasma sources, arc discharges, arc plasma sources, electron gun)
[2]
[3]
[4]
What is GDS or GDOES?
(“Glow Discharge Spectroscopy” or “Glow
Discharge Optical Emission
Spectroscopy”)
Low energy, high flux incident
ions sputter away surface
layers with minimum damage
to the bulk sample.
Emission spectrum is
measured to determine
composition, layer-by-layer.
** Image from Y. Hatano et al, 13th PFMC
Workshop (Rosenheim, May 09th - 13th, 2011)
PSI-2 linear facility
IR Camera
Re-entrant
Anode
RF
Source
Sample
Problems:
Laser beam
•
•
Containment of discharge
Containment of sputtered
species
Sample
To Spectrometer
or Filterscopes
Summary
 PSI-2 can provide a good opportunity to develop GDOES
as an in vacuo diagnostic for PMI applications
 Sufficient literature from surface science literature and
initial (ex-situ) application for fusion PMI
 Port access seems sufficient for a first, rudimentary set-up
 RF supplies and matching circuit element are available at
ORNL RF Lab
 Industrial systems already available and teaming with
manufacturers possible to get custom systems.
 Early proof-of-principle feasible on time to provide more
complete diagnostic for JULE-PSI and ORNL-PMTS
 Community participation is welcome.
[ 5 ] Use of the focusing multi-slit ion optical
system at the diagnostic injector RUDI
A.Listopad1, J.Coenen2, V.Davydenko1, A.Ivanov1, V.Mishagin1, V.Savkin1,
G.Shulzhenko1, B.Schweer2 and R.Uhlemann2
1Budker
Institute of Nuclear Physics SB RAS,
630090 Novosibirsk, RUSSIA
2
Trilateral Euregio Cluster, Institut fuer Energie- und Klimaforschung,
Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, 52425 Juelich,
Germany
[email protected]
Atomic driver based on arc generator
Lanthanum hexaboribe
thermocathode
Arc-discharge
channel
Water cooling
Converter
H0
Round and slit RUDI beamlet geometries
U1=50 kV
U2=43 kV
U3=-500 V
U4=0 V
BEAM
RUDI beam divergence scan at 45 kV (6,6 kV 1st gap)
Charge-eXchange Recombination Spectroscopy
DED
H-beam
Lower observation system
Toroidal
observation
system
Summary
• Optical beam diagnostic complex was developed
• New slit ion optics is introduced (June 2010)
• Beam current achieved 2,8A (at 49 kV, due to HV PS power
limit)
• Beam diameter at 2m ~3cm along the slits
• Beam species composition ~80% protons
• More than 100% CXRS signal level rise
• New arc-discharge element has provided 6-8 s beam duration