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Title: Responsivity calibration of the LoWEUS spectrometer

Abstract

We performed an in situ calibration of the relative responsivity function of the Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS), while operating on the Lithium Tokamak Experiment (LTX) at Princeton Plasma Physics Laboratory. The calibration was accomplished by measuring oxygen lines, which are typically present in LTX plasmas. The measured spectral line intensities of each oxygen charge state were then compared to the calculated emission strengths given in the CHIANTI atomic database. Normalizing the strongest line in each charge state to the CHIANTI predictions, we obtained the differences between the measured and predicted values for the relative strengths of the other lines of a given charge state. We find that a 3rd degree polynomial function provides a good fit to the data points. Lastly, our measurements show that the responsivity between about 120 and 300 Å varies by factor of ~30.

Authors:
 [1]; ORCiD logo [2];  [3];  [3]; ORCiD logo [3]
  1. Univ. of California, Berkeley, CA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1349666
Report Number(s):
LLNL-JRNL-698642
Journal ID: ISSN 0034-6748; RSINAK; TRN: US1701664
Grant/Contract Number:
AC02-09CH11466; AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 87; Journal Issue: 11; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 74 ATOMIC AND MOLECULAR PHYSICS; 70 PLASMA PHYSICS AND FUSION

Citation Formats

Lepson, J. K., Beiersdorfer, P., Kaita, R., Majeski, R., and Boyle, D. Responsivity calibration of the LoWEUS spectrometer. United States: N. p., 2016. Web. doi:10.1063/1.4960729.
Lepson, J. K., Beiersdorfer, P., Kaita, R., Majeski, R., & Boyle, D. Responsivity calibration of the LoWEUS spectrometer. United States. doi:10.1063/1.4960729.
Lepson, J. K., Beiersdorfer, P., Kaita, R., Majeski, R., and Boyle, D. 2016. "Responsivity calibration of the LoWEUS spectrometer". United States. doi:10.1063/1.4960729. https://www.osti.gov/servlets/purl/1349666.
@article{osti_1349666,
title = {Responsivity calibration of the LoWEUS spectrometer},
author = {Lepson, J. K. and Beiersdorfer, P. and Kaita, R. and Majeski, R. and Boyle, D.},
abstractNote = {We performed an in situ calibration of the relative responsivity function of the Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS), while operating on the Lithium Tokamak Experiment (LTX) at Princeton Plasma Physics Laboratory. The calibration was accomplished by measuring oxygen lines, which are typically present in LTX plasmas. The measured spectral line intensities of each oxygen charge state were then compared to the calculated emission strengths given in the CHIANTI atomic database. Normalizing the strongest line in each charge state to the CHIANTI predictions, we obtained the differences between the measured and predicted values for the relative strengths of the other lines of a given charge state. We find that a 3rd degree polynomial function provides a good fit to the data points. Lastly, our measurements show that the responsivity between about 120 and 300 Å varies by factor of ~30.},
doi = {10.1063/1.4960729},
journal = {Review of Scientific Instruments},
number = 11,
volume = 87,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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  • We performed an in situ calibration of the relative responsivity function of the Long-Wavelength Extreme Ultraviolet Spectrometer (LoWEUS), while operating on the Lithium Tokamak Experiment (LTX) at Princeton Plasma Physics Laboratory. The calibration was accomplished by measuring oxygen lines, which are typically present in LTX plasmas. The measured spectral line intensities of each oxygen charge state were then compared to the calculated emission strengths given in the CHIANTI atomic database. Normalizing the strongest line in each charge state to the CHIANTI predictions, we obtained the differences between the measured and predicted values for the relative strengths of the other linesmore » of a given charge state. We find that a 3rd degree polynomial function provides a good fit to the data points. Our measurements show that the responsivity between about 120 and 300 Å varies by factor of ∼30.« less
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