Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X

doi:10.1063/1.5037543

Title: Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X

Abstract

Here, we present a detailed overview and first results of the new laser blow-off system on the stellarator Wendelstein 7-X. The system allows impurity transport studies by the repetitive and controlled injection of different tracer ions into the plasma edge. A Nd:YAG laser is used to ablate a thin metal film, coated on a glass plate, with a repetition rate of up to 20 Hz. A remote-controlled adjustable optical system allows the variation of the laser spot diameter and enables the spot positioning to non-ablated areas on the target between laser pulses. During first experiments, clear spectral lines from higher ionization stages of the tracer ions have been observed in the X-ray to the extreme ultraviolet spectral range. The temporal behavior of the measured emission allows the estimate of transport properties, e.g., impurity transport times in the order of 100 ms. Although the strong injection of impurities is well detectable, the global plasma parameters are barely changed.

Authors:

^[1]; Geiger, B. ^[1]; Kunkel, F. ^[1]; Burhenn, R. ^[1];

^[1]; Biedermann, C. ^[1];

^[1]; Cseh, G. ^[2];

^[3]; Grulke, O. ^[1]; Hollfeld, K. ^[3];

^[1]; Kocsis, G. ^[2]; Krings, T. ^[3]; Langenberg, A. ^[1];

^[3]; Neuner, U. ^[1];

^[3]; Offermanns, G. ^[3];

^[4] more »

Max-Planck Inst. for Plasma Physics, Greifswald (Germany)
Wigner Research Center for Physics, Budapest (Hungary)
Forschungszentrum Julich (Germany)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Publication Date:: 2018-07-20

Research Org.:: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: USDOE; European Commission (EC)

Contributing Org.:: W7-X Team

OSTI Identifier:: 1473872

Grant/Contract Number:: 633053

Resource Type:: Accepted Manuscript

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 89; Journal Issue: 7; Journal ID: ISSN 0034-6748

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION

Citation Formats


                    Wegner, Th., Geiger, B., Kunkel, F., Burhenn, R., Schröder, T., Biedermann, C., Buttenschön, B., Cseh, G., Drews, P., Grulke, O., Hollfeld, K., Killer, C., Kocsis, G., Krings, T., Langenberg, A., Marchuk, O., Neuner, U., Nicolai, D., Offermanns, G., Pablant, N. A., Rahbarnia, K., Satheeswaran, G., Schilling, J., Schweer, B., Szepesi, T., and Thomsen, H. Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X.  United States: N. p., 2018. 
        Web.  doi:10.1063/1.5037543.

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                    Wegner, Th., Geiger, B., Kunkel, F., Burhenn, R., Schröder, T., Biedermann, C., Buttenschön, B., Cseh, G., Drews, P., Grulke, O., Hollfeld, K., Killer, C., Kocsis, G., Krings, T., Langenberg, A., Marchuk, O., Neuner, U., Nicolai, D., Offermanns, G., Pablant, N. A., Rahbarnia, K., Satheeswaran, G., Schilling, J., Schweer, B., Szepesi, T., & Thomsen, H. Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X.  United States.  doi:10.1063/1.5037543.

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                    Wegner, Th., Geiger, B., Kunkel, F., Burhenn, R., Schröder, T., Biedermann, C., Buttenschön, B., Cseh, G., Drews, P., Grulke, O., Hollfeld, K., Killer, C., Kocsis, G., Krings, T., Langenberg, A., Marchuk, O., Neuner, U., Nicolai, D., Offermanns, G., Pablant, N. A., Rahbarnia, K., Satheeswaran, G., Schilling, J., Schweer, B., Szepesi, T., and Thomsen, H. Fri .  
        "Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X".  United States.  doi:10.1063/1.5037543.  https://www.osti.gov/servlets/purl/1473872.

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@article{osti_1473872,

  title        = {Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X},

  author       = {Wegner, Th. and Geiger, B. and Kunkel, F. and Burhenn, R. and Schröder, T. and Biedermann, C. and Buttenschön, B. and Cseh, G. and Drews, P. and Grulke, O. and Hollfeld, K. and Killer, C. and Kocsis, G. and Krings, T. and Langenberg, A. and Marchuk, O. and Neuner, U. and Nicolai, D. and Offermanns, G. and Pablant, N. A. and Rahbarnia, K. and Satheeswaran, G. and Schilling, J. and Schweer, B. and Szepesi, T. and Thomsen, H.},

  abstractNote = {Here, we present a detailed overview and first results of the new laser blow-off system on the stellarator Wendelstein 7-X. The system allows impurity transport studies by the repetitive and controlled injection of different tracer ions into the plasma edge. A Nd:YAG laser is used to ablate a thin metal film, coated on a glass plate, with a repetition rate of up to 20 Hz. A remote-controlled adjustable optical system allows the variation of the laser spot diameter and enables the spot positioning to non-ablated areas on the target between laser pulses. During first experiments, clear spectral lines from higher ionization stages of the tracer ions have been observed in the X-ray to the extreme ultraviolet spectral range. The temporal behavior of the measured emission allows the estimate of transport properties, e.g., impurity transport times in the order of 100 ms. Although the strong injection of impurities is well detectable, the global plasma parameters are barely changed.},

  doi          = {10.1063/1.5037543},

  journal      = {Review of Scientific Instruments},

  number       = 7,

  volume       = 89,

  place        = {United States},

  year         = {2018},

  month        = {7}

}

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DOI: 10.1063/1.5037543

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Cited by: 9 works

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Figure 1: Schematic side view of the experimental setup with the result of the ray tracing calculation (red beam). The laser blow-off system is installed below the multi-purpose manipulator which is used for the positioning of the glass target holder inside the torus. The glass target holder, enlarged in themore »

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Works referenced in this record:

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Neutral and ion composition of laser produced lithium plasma plume in front and back ablation of thin film
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Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited)
journal, October 2018

Langenberg, A.; Pablant, N. A.; Wegner, Th.
Review of Scientific Instruments, Vol. 89, Issue 10
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Plasma impurities observed by a pulse height analysis diagnostic during the divertor campaign of the Wendelstein 7-X stellarator
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Kubkowska, M.; Czarnecka, A.; Fornal, T.
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Charge exchange recombination spectroscopy at Wendelstein 7-X
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Ford, O. P.; Vanó, L.; Alonso, J. A.
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Impurity transport studies at Wendelstein 7-X by means of x-ray imaging spectrometer measurements
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Plasma Physics and Controlled Fusion, Vol. 61, Issue 1
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Observation of anomalous impurity transport during low-density experiments in W7-X with laser blow-off injections of iron
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Similar Records

Title: Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X

Abstract

Citation Formats

Figures / Tables:

Measurements of n e ( r ) and T e ( r ) in TdeV boundary layer by injection of laser ablated Li and C journal, December 1992

Laboratory study of the PDX/PLT laser blow‐off trace element injectors journal, April 1982

Development and manufacturing of CIS thin film solar modules journal, February 2001

Derivation of local impurity transport quantities from soft-x radiation evolution during tracer injection at W7-AS journal, January 1999

Selective ablation of thin Mo and TCO films with femtosecond laser pulses for structuring thin film solar cells journal, June 2007

A simple method of impurity injection into tokamak plasmas journal, April 1989

On plasma ion beam formation in the Advanced Plasma Source journal, May 2012

Effects of Internal Disruptions on Impurity Transport in Tokamaks journal, August 1983

Atomic and ionic beam source utilizing pulsed laser blow off journal, January 1976

Impurity Transport in a Mixed-Collisionality Stellarator Plasma journal, April 2017

Impurities in tokamaks journal, December 1984

Startup impurity diagnostics in Wendelstein 7-X stellarator in the first operational phase journal, October 2015

Diamagnetic energy measurement during the first operational phase at the Wendelstein 7-X stellarator journal, July 2018

Laser ablation of thin molybdenum films on transparent substrates at low fluences journal, August 2010

Transient electron heat diffusivity obtained from trace impurity injection on TFTR journal, March 1994

An experimental counter‐example to the local transport paradigm journal, June 1995

Measurement of the scrape‐off layer density profile on ASDEX via an energetic neutral lithium beam journal, May 1985

System for rapid injection of metal atoms into plasmas journal, September 1975

Edge plasma density measurement by laser blow-off method journal, May 1989

On impurity handling in high performance stellarator/heliotron plasmas journal, April 2009

Fluctuation measurements on the Wendelstein 7-AS stellarator by means of repetitive lithium laser blow-off journal, February 2004

Laboratory studies of metal atomic beams produced by means of UV-laser radiation journal, May 1997

Understanding Thin Film Laser Ablation: The Role of the Effective Penetration Depth and the Film Thickness journal, January 2014

Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited) journal, October 2018

Impurity Transport in a Quiescent Tokamak Plasma journal, December 1975

Transport studies using laser blow-off injection of low- Z trace impurities injected into the TJ-II stellarator journal, May 2011

Design of a high–efficiency extreme ultraviolet overview spectrometer system for plasma impurity studies on the stellarator experiment Wendelstein 7-X journal, September 2004

Propagation of cold pulses and heat pulses in ASDEX Upgrade journal, November 2000

Use of laser‐ablated fast particle beams for the measurement of n e and T e profiles in the TEXTOR boundary layer journal, August 1988

Laser‐generated pulsed atomic beams journal, January 1974

Characterization of laser-ablation plasmas journal, July 1999

Characterization of impurity confinement on Alcator C-Mod using a multi-pulse laser blow-off system journal, March 2011

Metal deposition from a supported metal film using an excimer laser journal, August 1986

A multi-purpose manipulator system for W7-X as user facility for plasma edge investigation journal, November 2017

Laser blow‐off lithium beam probing with high temporal resolution for edge plasma diagnostics journal, August 1993

Density control problems in large stellarators with neoclassical transport journal, August 1999

Core Impurity Transport Studies from Different Diagnostic Approaches in LHD journal, August 2010

Effects of plasma shape on laser blow-off injected impurity transport in TCV journal, October 2003

Compact imaging Bragg spectrometer for fusion devices journal, October 2004

Acceleration characteristics of spherical and nonspherical pellets by the LHD impurity pellet injector journal, March 2003

Impurity transport in JET using laser injected impurities in Ohmic and radiofrequency heated plasmas journal, October 1990

Time-resolved study of back side ablated molybdenum thin films by ultrashort laser pulses journal, August 2012

Forward Modeling of X-Ray Imaging Crystal Spectrometers Within the Minerva Bayesian Analysis Framework journal, April 2016

Time-integrated reflectivity of laser-induced back-ablated aluminum thin film targets journal, August 1997

Plasma Based Synthesis, Electron Microscopy, and Optical Characterization of Au-, Ag-, and Ag/Au-Core–Shell Nanoparticles journal, December 2014

Overview video diagnostics for the W7-X stellarator journal, October 2015

Neutral and ion composition of laser produced lithium plasma plume in front and back ablation of thin film journal, January 2019

Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited) journal, October 2018

Plasma impurities observed by a pulse height analysis diagnostic during the divertor campaign of the Wendelstein 7-X stellarator journal, October 2018

Charge exchange recombination spectroscopy at Wendelstein 7-X journal, February 2020

Impurity transport studies at Wendelstein 7-X by means of x-ray imaging spectrometer measurements journal, November 2018

Observation of anomalous impurity transport during low-density experiments in W7-X with laser blow-off injections of iron journal, February 2019

Overview of first Wendelstein 7-X high-performance operation journal, June 2019

Plasma termination by excess pellet fueling and impurity injection in TJ-II, the Large Helical Device and Wendelstein 7-X journal, May 2019

Characterization of the W7-X scrape-off layer using reciprocating probes journal, June 2019

Measurements of n _e ( r ) and T _e ( r ) in TdeV boundary layer by injection of laser ablated Li and C
journal, December 1992

Laboratory study of the PDX/PLT laser blow‐off trace element injectors
journal, April 1982

Development and manufacturing of CIS thin film solar modules
journal, February 2001

Derivation of local impurity transport quantities from soft-x radiation evolution during tracer injection at W7-AS
journal, January 1999

Selective ablation of thin Mo and TCO films with femtosecond laser pulses for structuring thin film solar cells
journal, June 2007

A simple method of impurity injection into tokamak plasmas
journal, April 1989

On plasma ion beam formation in the Advanced Plasma Source
journal, May 2012

Effects of Internal Disruptions on Impurity Transport in Tokamaks
journal, August 1983

Atomic and ionic beam source utilizing pulsed laser blow off
journal, January 1976

Impurity Transport in a Mixed-Collisionality Stellarator Plasma
journal, April 2017

Impurities in tokamaks
journal, December 1984

Startup impurity diagnostics in Wendelstein 7-X stellarator in the first operational phase
journal, October 2015

Diamagnetic energy measurement during the first operational phase at the Wendelstein 7-X stellarator
journal, July 2018

Laser ablation of thin molybdenum films on transparent substrates at low fluences
journal, August 2010

Transient electron heat diffusivity obtained from trace impurity injection on TFTR
journal, March 1994

An experimental counter‐example to the local transport paradigm
journal, June 1995

Measurement of the scrape‐off layer density profile on ASDEX via an energetic neutral lithium beam
journal, May 1985

System for rapid injection of metal atoms into plasmas
journal, September 1975

Edge plasma density measurement by laser blow-off method
journal, May 1989

On impurity handling in high performance stellarator/heliotron plasmas
journal, April 2009

Fluctuation measurements on the Wendelstein 7-AS stellarator by means of repetitive lithium laser blow-off
journal, February 2004

Laboratory studies of metal atomic beams produced by means of UV-laser radiation
journal, May 1997

Understanding Thin Film Laser Ablation: The Role of the Effective Penetration Depth and the Film Thickness
journal, January 2014

Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited)
journal, October 2018

Impurity Transport in a Quiescent Tokamak Plasma
journal, December 1975

Transport studies using laser blow-off injection of low- Z trace impurities injected into the TJ-II stellarator
journal, May 2011

Design of a high–efficiency extreme ultraviolet overview spectrometer system for plasma impurity studies on the stellarator experiment Wendelstein 7-X
journal, September 2004

Propagation of cold pulses and heat pulses in ASDEX Upgrade
journal, November 2000

Use of laser‐ablated fast particle beams for the measurement of n _e and T _e profiles in the TEXTOR boundary layer
journal, August 1988

Laser‐generated pulsed atomic beams
journal, January 1974

Characterization of laser-ablation plasmas
journal, July 1999

Characterization of impurity confinement on Alcator C-Mod using a multi-pulse laser blow-off system
journal, March 2011

Metal deposition from a supported metal film using an excimer laser
journal, August 1986

A multi-purpose manipulator system for W7-X as user facility for plasma edge investigation
journal, November 2017

Laser blow‐off lithium beam probing with high temporal resolution for edge plasma diagnostics
journal, August 1993

Density control problems in large stellarators with neoclassical transport
journal, August 1999

Core Impurity Transport Studies from Different Diagnostic Approaches in LHD
journal, August 2010

Effects of plasma shape on laser blow-off injected impurity transport in TCV
journal, October 2003

Compact imaging Bragg spectrometer for fusion devices
journal, October 2004

Acceleration characteristics of spherical and nonspherical pellets by the LHD impurity pellet injector
journal, March 2003

Impurity transport in JET using laser injected impurities in Ohmic and radiofrequency heated plasmas
journal, October 1990

Time-resolved study of back side ablated molybdenum thin films by ultrashort laser pulses
journal, August 2012

Forward Modeling of X-Ray Imaging Crystal Spectrometers Within the Minerva Bayesian Analysis Framework
journal, April 2016

Time-integrated reflectivity of laser-induced back-ablated aluminum thin film targets
journal, August 1997

Plasma Based Synthesis, Electron Microscopy, and Optical Characterization of Au-, Ag-, and Ag/Au-Core–Shell Nanoparticles
journal, December 2014

Overview video diagnostics for the W7-X stellarator
journal, October 2015

Neutral and ion composition of laser produced lithium plasma plume in front and back ablation of thin film
journal, January 2019

Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited)
journal, October 2018

Plasma impurities observed by a pulse height analysis diagnostic during the divertor campaign of the Wendelstein 7-X stellarator
journal, October 2018

Charge exchange recombination spectroscopy at Wendelstein 7-X
journal, February 2020

Impurity transport studies at Wendelstein 7-X by means of x-ray imaging spectrometer measurements
journal, November 2018

Observation of anomalous impurity transport during low-density experiments in W7-X with laser blow-off injections of iron
journal, February 2019

Overview of first Wendelstein 7-X high-performance operation
journal, June 2019

Plasma termination by excess pellet fueling and impurity injection in TJ-II, the Large Helical Device and Wendelstein 7-X
journal, May 2019

Characterization of the W7-X scrape-off layer using reciprocating probes
journal, June 2019