Multi-energy reconstructions, central electron temperature measurements, and early detection of the birth and growth of runaway electrons using a versatile soft x-ray pinhole camera at MST

Delgado-Aparicio, L. F.; VanMeter, P.; Barbui, T.; Chellai, O.; Wallace, J.; Yamazaki, H.; Kojima, S.; Almagari, A. F.; Hurst, N. C.; Chapman, B. E.; McCollam, K. J.; Den Hartog, D. J.; Sarff, J. S.; Reusch, L. M.; Pablant, N.; Hill, K.; Bitter, M.; Ono, M.; Stratton, B.; Takase, Y.; Luethi, B.; Rissi, M.; Donath, T.; Hofer, P.; Pilet, N.

doi:10.1063/5.0043672

Title: Multi-energy reconstructions, central electron temperature measurements, and early detection of the birth and growth of runaway electrons using a versatile soft x-ray pinhole camera at MST

Journal Article · 01 July 2021 · Review of Scientific Instruments

DOI: https://doi.org/10.1063/5.0043672 · OSTI ID:1805056

;

; Yamazaki, H.;

; Almagari, A. F.;

;

; McCollam, K. J.; Den Hartog, D. J.; Sarff, J. S.; Reusch, L. M.;

;

; Bitter, M.;

; Stratton, B.;

A multi-energy soft x-ray pinhole camera has been designed, built, and deployed at the Madison Symmetric Torus to aid the study of particle and thermal transport, as well as MHD stability physics. This novel imaging diagnostic technique employs a pixelated x-ray detector in which the lower energy threshold for photon detection can be adjusted independently on each pixel. The detector of choice is a PILATUS3 100 K with a 450 μm thick silicon sensor and nearly 100 000 pixels sensitive to photon energies between 1.6 and 30 keV. An ensemble of cubic spline smoothing functions has been applied to the line-integrated data for each time-frame and energy-range, obtaining a reduced standard-deviation when compared to that dominated by photon-noise. The multi-energy local emissivity profiles are obtained from a 1D matrix-based Abel-inversion procedure. Central values of Te can be obtained by modeling the slope of the continuum radiation from ratios of the inverted radial emissivity profiles over multiple energy ranges with no a priori assumptions of plasma profiles, magnetic field reconstruction constraints, high-density limitations, or need of shot-to-shot reproducibility. In tokamak plasmas, a novel application has recently been tested for early detection, 1D imaging, and study of the birth, exponential growth, and saturation of runaway electrons at energies comparable to 100 × Te,0; thus, early results are also presented.

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Sponsoring Organization:: USDOE

Grant/Contract Number:: AC02-09CH11466

OSTI ID:: 1805056

Journal Information:: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 7 Vol. 92; ISSN 0034-6748

Publisher:: American Institute of PhysicsCopyright Statement

Country of Publication:: United States

Language:: English

References (21)

FLYCHK: Generalized population kinetics and spectral model for rapid spectroscopic analysis for all elements Chung, H. -K.; Chen, M. H.; Morgan, W. L. High Energy Density Physics, Vol. 1, Issue 1 https://doi.org/10.1016/j.hedp.2005.07.001	journal	December 2005
Inversion technique to obtain an emissivity profile from tangential line‐integrated hard x‐ray measurements Bell, Ronald E. Review of Scientific Instruments, Vol. 66, Issue 1 https://doi.org/10.1063/1.1146350	journal	January 1995
Soft x-ray continuum radiation transmitted through metallic filters: An analytical approach to fast electron temperature measurements Delgado-Aparicio, L.; Tritz, K.; Kramer, T. Review of Scientific Instruments, Vol. 81, Issue 10 https://doi.org/10.1063/1.3474641	journal	October 2010
Novel energy resolving x-ray pinhole camera on Alcator C-Mod Pablant, N. A.; Delgado-Aparicio, L.; Bitter, M. Review of Scientific Instruments, Vol. 83, Issue 10 https://doi.org/10.1063/1.4732177	journal	October 2012
Optimization of the configuration of pixilated detectors based on the Shannon-Nyquist theory Wang, E.; Beiersdorfer, P.; Bitter, M. Review of Scientific Instruments, Vol. 83, Issue 10 https://doi.org/10.1063/1.4746998	journal	October 2012
Growth and decay of runaway electrons above the critical electric field under quiescent conditions Paz-Soldan, C.; Eidietis, N. W.; Granetz, R. Physics of Plasmas, Vol. 21, Issue 2 https://doi.org/10.1063/1.4866912	journal	February 2014
An integrated data analysis tool for improving measurements on the MST RFP Reusch, L. M.; Galante, M. E.; Franz, P. Review of Scientific Instruments, Vol. 85, Issue 11 https://doi.org/10.1063/1.4886957	journal	November 2014
Multi-energy x-ray detector calibration for Te and impurity density (nZ) measurements of MCF plasmas Maddox, J.; Pablant, N.; Efthimion, P. Review of Scientific Instruments, Vol. 87, Issue 11 https://doi.org/10.1063/1.4960602	journal	August 2016
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited) Delgado-Aparicio, L. F.; Maddox, J.; Pablant, N. Review of Scientific Instruments, Vol. 87, Issue 11 https://doi.org/10.1063/1.4964807	journal	November 2016
Resolving runaway electron distributions in space, time, and energy Paz-Soldan, C.; Cooper, C. M.; Aleynikov, P. Physics of Plasmas, Vol. 25, Issue 5 https://doi.org/10.1063/1.5024223	journal	May 2018
Pixel-to-pixel variation on a calibrated PILATUS3-based multi-energy soft x-ray detector VanMeter, P.; Delgado-Aparicio, L. F.; Reusch, L. Review of Scientific Instruments, Vol. 89, Issue 10 https://doi.org/10.1063/1.5037347	journal	October 2018
A computational tool for simulation and design of tangential multi-energy soft x-ray pin-hole cameras for tokamak plasmas Yamazaki, H.; Delgado-Aparicio, L. F.; Groebner, R. Review of Scientific Instruments, Vol. 89, Issue 10 https://doi.org/10.1063/1.5038788	journal	October 2018
Simulation, design, and first test of a multi-energy soft x-ray (SXR) pinhole camera in the Madison Symmetric Torus (MST) Delgado-Aparicio, L. F.; Wallace, J.; Yamazaki, H. Review of Scientific Instruments, Vol. 89, Issue 10 https://doi.org/10.1063/1.5038798	journal	October 2018
Determination of Z _eff by integrating measurements from x-ray tomography and charge exchange recombination spectroscopy Galante, M. E.; Reusch, L. M.; Den Hartog, D. J. Nuclear Fusion, Vol. 55, Issue 12 https://doi.org/10.1088/0029-5515/55/12/123016	journal	November 2015
A ‘multi-colour’ SXR diagnostic for time and space-resolved measurements of electron temperature, MHD activity and particle transport in MCF plasmas Delgado-Aparicio, L. F.; Stutman, D.; Tritz, K. Plasma Physics and Controlled Fusion, Vol. 49, Issue 8 https://doi.org/10.1088/0741-3335/49/8/010	journal	July 2007
Generation and suppression of runaway electrons in MST tokamak plasmas Munaretto, S.; Chapman, B. E.; Cornille, B. S. Nuclear Fusion, Vol. 60, Issue 4 https://doi.org/10.1088/1741-4326/ab73c0	journal	March 2020
Reduced Edge Instability and Improved Confinement in the MST Reversed-Field Pinch Chapman, B. E.; Anderson, J. K.; Biewer, T. M. Physical Review Letters, Vol. 87, Issue 20 https://doi.org/10.1103/PhysRevLett.87.205001	journal	October 2001
Fluctuation and transport reduction in a reversed field pinch by inductive poloidal current drive Sarff, J. S.; Hokin, S. A.; Ji, H. Physical Review Letters, Vol. 72, Issue 23 https://doi.org/10.1103/physrevlett.72.3670	journal	June 1994
Performance of single-photon-counting PILATUS detector modules Kraft, P.; Bergamaschi, A.; Broennimann, Ch. Journal of Synchrotron Radiation, Vol. 16, Issue 3 https://doi.org/10.1107/s0909049509009911	journal	April 2009
Characterization and Calibration of PILATUS Detectors Kraft, P.; Bergamaschi, A.; Bronnimann, Ch. IEEE Transactions on Nuclear Science, Vol. 56, Issue 3 https://doi.org/10.1109/TNS.2008.2009448	journal	June 2009
The Madison Symmetric Torus Dexter, R. N.; Kerst, D. W.; Lovell, T. W. Fusion Technology, Vol. 19, Issue 1 https://doi.org/10.13182/fst91-a29322	journal	January 1991

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