DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Machine learning-aided line intensity ratio technique applied to deuterium plasmas

Journal Article · · AIP Advances
DOI: https://doi.org/10.1063/5.0147463 · OSTI ID:1972220

It has been demonstrated that the electron density, ne, and temperature, Te, are successfully evaluated from He I line intensity ratios coupled with machine learning (ML). In this paper, the ML-aided line intensity ratio technique is applied to deuterium (D) plasmas with 0.031 < ne (1018 m–3) < 0.67 and 2.3 < Te (eV) < 5.1 in the PISCES-A linear plasma device. Two line intensity ratios, Dα/Dγ and Dα/Dβ, are used to develop a predictive model for ne and Te separately. Reasonable agreement of both ne and Te with those from single Langmuir probe measurements is obtained at ne > 0.1 × 1018 m–3. Addition of the D2/Dα intensity ratio, where the D2 band emission intensity is integrated in a wavelength range of λ ~ 557.4–643.0 nm, is found to improve the prediction of, in particular, ne, and Te. It is also confirmed that the technique works for D plasmas with 0.067 < ne (1018 m–3) < 6.1 and 0.8 < Te (eV) < 15 in another linear plasma device, PISCES-RF. The two training datasets from PISCES-A and PISCES-RF are combined, and unified predictive models for ne and Te give reasonable agreement with probe measurements in both devices.

Research Organization:
Univ. of California, San Diego, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
SC0022528; FG02-07ER54912
OSTI ID:
1972220
Journal Information:
AIP Advances, Vol. 13, Issue 5; ISSN 2158-3226
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

References (35)

Application of passive spectroscopy to the He I line intensity ratio technique: a new tool for electron temperature and density measurement in fusion boundary plasmas journal May 2001
Machine learning prediction of electron density and temperature from He I line ratios journal February 2021
Comparison of He I line intensity ratio method and electrostatic probe for electron density and temperature measurements in NAGDIS-II journal January 2006
PISCES-RF: a liquid-cooled high-power steady-state helicon plasma device journal May 2021
Hydrogen‐atom spectroscopy of the ionizing plasma containing molecular hydrogen: Line intensities and ionization rate journal June 1993
Formation of helium induced nanostructure ‘fuzz’ on various tungsten grades journal September 2010
New application of hyperspectral imaging to steady-state plasma observations journal August 2020
Space Charge Waves in Cylindrical Plasma Columns journal November 1959
Application of multiple regression for sensitivity analysis of helium line emissions to the electron density and temperature in Magnum-PSI journal April 2021
Collisional-radiative model for neutral helium in plasma revisited journal February 2003
On the measurement of molecular particle fluxes in fusion boundary plasmas journal March 2003
Status of electron temperature and density measurement with beam emission spectroscopy on thermal helium at TEXTOR journal September 2008
Particle influx measurements in jet helium plasmas using a multichannel visible spectrometer journal April 1989
Implementation of a new atomic basis for the He I equilibrium line ratio technique for electron temperature and density diagnostic in the SOL for H-mode plasmas in DIII-D journal August 2011
Validation of 2D Te and ne measurements made with Helium imaging spectroscopy in the volume of the TCV divertor journal February 2023
Helium I line intensity ratios in a plasma for the diagnostics of fusion edge plasmas journal October 1996
Use of machine learning for a helium line intensity ratio method in Magnum-PSI journal October 2022
Electron temperature and electron density profiles measured with a thermal He-beam in the plasma boundary of TEXTOR journal December 1992
Edge temperature and density measurements with a thermal helium beam in the RFX reversed field pinch journal December 1999
Determination of the optical escape factor in the He I line intensity ratio technique applied for weakly ionized plasmas journal April 2007
Influence of plasma impurities on the fuel retention in tungsten journal June 2019
Optical diagnostics with radiation trapping effect in low density and low temperature helium plasma journal June 2016
Yacora on the Web: Online collisional radiative models for plasmas containing H, H2 or He journal January 2020
Microscopic damage of tungsten exposed to deuterium–helium mixture plasma in PISCES and its impacts on retention property journal August 2011
Spectroscopic measurement of atomic and molecular deuterium fluxes in the DIII-D plasma edge journal July 2006
Electron temperature measurement by a helium line intensity ratio method in helicon plasmas journal December 2001
Effect of He on D retention in W exposed to low-energy, high-fluence (D, He, Ar) mixture plasmas journal August 2011
Observations of suppressed retention and blistering for tungsten exposed to deuterium–helium mixture plasmas journal May 2009
Plasma surface interaction experimental facility (PISCES) for materials and edge physics studies journal May 1984
Interpretation of spatially resolved helium line ratios on MAST journal June 2009
Rough-surface effect on sputtering of Cr bombarded by low-energy He plasma journal December 2021
Helium line ratio spectroscopy for high spatiotemporal resolution plasma edge profile measurements at ASDEX Upgrade (invited) journal October 2018
Emission spectroscopy of He lines in high-density plasmas in Magnum-PSI journal February 2020
The role of hydrogen molecular effects on detachment in Magnum-PSI journal October 2020
Testing of the collisonal-radiative model by laser-induced perturbation of a supersonic He beam in TJ-II plasmas journal March 2006