Arkadi Kreter on behalf of FZJ PWI team
Institute for Energy and Climate Research - Plasma Physics, Forschungszentrum Jülich,
Association EURATOM-FZJ, Trilateral Euregio Cluster, Germany
2 nd International Workshop on Plasma Material Interaction Facilities for Fusion Research (PMIF)
Jülich, Germany, 19 September 2011

Based on PSI-2 / PISCES type device
Installation in a Hot Cell for handling of
radioactive and toxic materials
Plasma source
PMI studies with
• Neutron irradiated materials
• All wall materials incl. Beryllium
• Low quantities of Tritium
Schematic view
Target chamber Surface analysis Linear manipulator

Talk by B. Unterberg
PSI-2 is the pilot experiment of the JULE-PSI project
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 2

Formerly operated by IPP-Garching at Humboldt Univ., Berlin

PSI-1 was first operated in 1992

Upgrade to PSI-2 in 1998: extended target chamber with 2 additional coils

Transfer to FZJ in October 2009
PSI-2 installation in Berlin
Arkadi Kreter
1 m
“PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 3

 Transferred from Berlin to Jülich in October 2009
 First plasma in Jülich in January 2011

Idea: Existing PSI-2 as the pilot experiment of the JULE-PSI project, outside of hot cell

Name: PSI2 (Jülich)

Goals:
 Gain experience operating linear plasma device
 Test of components for JULE-PSI
• Prototype of target station
•
Plasma source optimization
• Diagnostics
• Other peripheral components
 Contribute to current PMI research topics
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 4

Current status corresponds to the installation in Berlin before transport
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 5

Text from IEK-4 news web site of 7/Jan/2011
First plasma in PSI2 Jülich
Today, Friday 7th of January 2011, 6.30 pm, the very first Argon discharge has been produced in the PSI-
2 Jülich device. This achievement constitutes a major milestone for our PSI programme on linear devices, which aims at the investigation of PSI processes with neutron activated fusion materials with the linear plasma device JULE-PSI in the Hot Material Laboratory
(HML) of FZJ. PSI2 Jülich will serve as a pilot experiment for this development and supplement our portfolio of facilities for the joint TEC programme on plasma-surface interactions.
Many thanks to the whole PSI-2 team, in particular to our colleagues from Berlin, Werner
Bohmeyer and Achim Mans.
Arkadi Kreter
Since August 2011 routine operation in deuterium
“PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 6

n e
[m -3 ]
< 10 19
For deuterium plasma
Te [eV] Flux [m -2 s -1 ]
< 20 < 10 23
E i
[eV]
10 – 300 (bias)
Example of Ar plasma profile at target position
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 7

• Arc discharge up to 1000 A and 150 V
• Typical regime of operation:
• Heating up and cooling down ~60 min
•
Steady-state plasma of several hours per day
•
Change of discharge parameters (incl. working gas) on one day possible
• Exchange of the cathode every 12 – 18 months
• Advantages:
•
Larger emitter area
 more efficient plasma production
•
Less prone to break due to thermal stresses
• Observation through the aperture
• Drawback (decisive):
•
Hollow plasma profile
Cylindrical cathode w/o heat shield
Cylindrical cathode assembly
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 8

• Originally designed by H. Greuner
• Partially constructed and tested in Berlin, but never in plasma operation
• Currently: optimization of design and testing
• Installation on PSI-2 is planned for Dec. 2011
Heater of disc-shaped cathode Disc-shaped cathode assembly
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 9


Options to optimize arc source performance / reliability are analysed in collaboration with the Budker Institute
 talk by A. Ivanov (for V. Davydenko)

Alternatively, helicon-type plasma source is considered, also in collaboration with the Budker Institute
• Synergy from the helicon source development at ORNL?
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 10

• First stage: side-fed manipulator from Berlin
• Currently being refurbished and adapted for our purposes
• To be installed in Oct 2011
• Second stage: new target station
PSI-2 current installation
Layout of sample holder in plasma
Side-fed manipulator support structure
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 11

Plasma source Typical target position
Exchange and
Analysis chamber
Target manipulator
• Serves as prototype of JULE-PSI target station
 talk by B. Unterberg
• Currently being manufactured
• Installation by the end of 2011
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 12

PSI-2 serves as test-bed for diagnostic development for JULE-PSI

Focus on reliability and easy maintenance
Plasma diagnostics (characterization of background plasma)
• Optical spectroscopy
• Langmuir probe
•
Thomson scattering being considered as substitute of Langmuir probe
In-situ PMI diagnostics
• Optical spectroscopy
•
IR thermography
•
Quartz microbalance (QMB)
In-vacuo sample analysis
Target station: linear manipulator and surface analysis station with
• Laser-aided analysis methods (LID, LIBS)
 talk by B. Unterberg
• Glow discharge spectroscopy
 talk by C. Klepper
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 13

Spectrometer systems available: i) Direct imaging spectrometer at the target
Spectrometer Acton 0.75m (SP2750 UV-VIS-NIR) with detector 2D EMCCD Andor NEWTON DU971 1600 x 400 ii) Fibre-coupled spectrometer in Littrow arrangement (10 nm coverage @ R=20000)
Spectrometer 0.75 m Echelle optimised for VIS with detector 2D EMCCD Andor IXON DU888 EC 1024 x 1024 iii) Fibre-coupled spectrometer in Littrow arrangement (2 nm coverage @ R=100000)
Spectrometer 1.25 m Echelle optimised for VIS with detector 2D EMCCD Andor IXON DU888 EC 1024 x 1024 iv) 2 sets of 4 channel compact spectrometers (300-858 nm @ R= 7500)
Avantes set (JET KT1-type with 1800 l/mm and 10
 m slit):
Ch.1 300-455 nm, ch.2 450-577 nm, ch.3 575-681 nm, ch.4 658-858 nm v) Overview compact spectrometer
Avantes 300 -1100 nm with 300 l/mm and 10
 m slit vi) Spectrelle and deep UV compact spectrometer to be shared with TEXTOR
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 14

•
High-precision balance (0.1
 g)

Weight loss measurements
• Thermal desorption spectrometry (TDS)

Retention with temperature resolution
• SEM / EDX

Morphology / Elemental composition
• Ion beam analyses: NRA, RBS,..

Absolute amounts of surface materials, limited depth resolution
•
Secondary Ion Mass Spectrometry (SIMS)

Depth distribution of elements
• X-ray Photoelectron Spectrometry (XPS)

Chemical composition and state (e.g. carbidization)
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 15

Recombining deuterium plasma
• Plasma characterization
• Hydrogen and impurity spectroscopy
•
Fuel retention in tungsten and graphite under the influence of impurities
• Erosion of tungsten and tungsten spectroscopy
• Simulation of transient heat loads by laser
(collaboration with Budker Institute)

Talks by A. Burdakov and A. Shoshin
• EUROFER as first wall material
Neutralizer plate
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 16


PSI-2 to serve as pilot experiment for JULE-PSI
 Transferred from Berlin to Jülich and successfully taken into operation

New components (cathode, target station, laser, diagnostics) purchased and partially delivered and commissioned

Physics programme started with plasma characterization and spectroscopic studies

PMI programme to start from October 2011
Arkadi Kreter “PSI-2 - the pilot experiment of the JULE-PSI project" PMIF, Jülich, 19 Sep 2011 17