- By:
- Kafle, Nischal ; Elliott, Drew B; Berlinger, Bruce; He, Zichen ; Cohen, Samuel; Zhang, Zhili ; Biewer, Theodore M
- Journal Name:
- Review of Scientific Instruments
- Page Number:
- 113506
- Volume:
- 93
- Issue Number:
- 11
- Publication Date:
- December 27, 2023
- Conference Name:
- High-Temperature Plasma Diagnostics Conference
- Conference Location:
- Rochester, New York, United States of America
- Conference Sponsor:
- NA
- View DOI Listing:
- https://doi.org/10.1063/5.0101849
Abstract
An Advanced Research Projects Agency-Energy funded diagnostic system has been deployed to the Princeton field-reversed configuration 2 (PFRC-2) device, located at Princeton Plasma Physics Laboratory. The Portable Diagnostic Package (PDP), designed at Oak Ridge National Laboratory, allows for the measurement of Thomson Scattering (TS) for electron density and temperature and Optical Emission Spectroscopy (OES) for ion temperature, impurity density, and ion velocity. A tunable spectrometer on the PDP with three gratings provides the flexibility to measure low (1 eV) and high (1000 eV) electron temperature ranges from TS. Additionally, using a second spectrometer, the OES diagnostic can survey light emission from various ion excitation levels for wide wavelength ranges. The electron density (1 × 1020 m−3 for the PDP. A recently implemented narrow-band notch spectral filter that masks the second harmonic 532 nm Nd:YAG laser wavelength has increased the system’s TS light discrimination sensitivity 65 times compared to the instance when the notch filter was not implemented. The hardware implementation including design changes to the flight tubes and Brewster windows will be discussed, along with results from Rayleigh and rotational Raman scattering sensitivity analyses, which were used to establish a quantitative figure of merit on the system performance. The Raman scattering calibration with the notch filter has improved the PDP electron density threshold to 1 ± 0.5 × 1018 m−3.
