Vacuum ultraviolet radiometry 3: The argon mini-arc as a new secondary standard of spectral radiance

Bridges, J. M.; Ott, William R.

doi:10.1364/ao.16.000367

Cited by 123 publications

(36 citation statements)

References 6 publications

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“…More detail is available in recent work on V I . Our heavily used D 2 lamp is periodically checked against another NIST-traceable D 2 lamp that has far fewer hours of operation, and against a windowless Ar miniarc (Bridges & Ott 1977) calibrated personally by Dr. Bridges at NIST. The echelle data on Co I are primarily used in the UV to provide better sensitivity, test for optical depth errors, and test the UV calibration of the FTS data.…”

Section: Branching Fraction Measurements For Lines Of Co Imentioning

confidence: 99%

IMPROVED Co i log( gf ) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

Lawler

Sneden

Cowan

2015

ApJS

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New emission branching fraction measurements for 898 lines of the first spectrum of cobalt (Co I) are determined from hollow cathode lamp spectra recorded with the National Solar Observatory 1 m Fourier transform spectrometer on Kitt Peak, AZ and a high-resolution echelle spectrometer. Published radiative lifetimes from laser induced fluorescence measurements are combined with the branching fractions to determine accurate absolute atomic transition probabilities for the 898 lines. Hyperfine structure (hfs) constants for levels of neutral Co in the literature are surveyed and selected values are used to generate complete hfs component patterns for 195 transitions of Co I. These new laboratory data are applied to determine the Co abundance in the Sun and metal-poor star HD 84937, yielding log ε(Co) = 4.955 ± 0.007 (σ = 0.059) based on 82 Co I lines and log ε(Co) = 2.785 ± 0.008 (σ = 0.065) based on 66 Co I lines, respectively. A Saha or ionization balance test on the photosphere of HD 84937 is performed using 16 UV lines of Co II, and good agreement is found with the Co I result in this metal-poor ([Fe I/H] = −2.32, [Fe II/H] = −2.32) dwarf star. The resulting value of [Co/Fe] = +0.14 supports a rise of Co/ Fe at low metallicity that has been suggested in other studies.

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Section: Branching Fraction Measurements For Lines Of Co Imentioning

confidence: 99%

IMPROVED Co i log( gf ) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

Lawler

Sneden

Cowan

2015

ApJS

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“…Examples include argon arcs (Bridges and Ott 1977), bare metal photoemissive diodes (Saloman 1978), D 2 lamps (Klose et al 1988), tungsten-filament incandescent lamps (Waters et al 1988), hollow-cathode (Danzmann et al 1988;Hollandt et al 1994) and Penning (Heise et al 1994) discharges, and silicon trap detectors (Goebel et al 1996) and photodiodes (Kuschnerus et al 1998;Canfield et al 1998). …”

Section: Transfer Standardsmentioning

confidence: 99%

Spectroradiometry with space telescopes

Pauluhn

Huber

Smith

et al. 2015

Astron Astrophys Rev

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Radiometry, i.e. measuring the power of electromagnetic radiationhitherto often referred to as "photometry"-is of fundamental importance in astronomy. We provide an overview of how to achieve a valid laboratory calibration of space telescopes and discuss ways to reliably extend this calibration to the spectroscopic telescope's performance in space. A lot of effort has been, and still is going into radiometric "calibration" of telescopes once they are in space; these methods use celestial primary and transfer standards and are based in part on stellar models. The history of the calibration of the Hubble Space Telescope serves as a platform to review these methods. However, we insist that a true calibration of spectroscopic space telescopes must directly be based on and traceable to laboratory standards, and thus be independent of the observations. This has recently become a well-supported aim, following the discovery of the acceleration of the cosmic expansion by use of type-Ia supernovae, and has led to plans for launching calibration rockets for the visible and infrared spectral range. This is timely, too, because an adequate exploitation of data from present space missions, such as Gaia, and from many current astronomical projects like Euclid and WFIRST demands higher radiometric accuracy than is generally available today. A survey of the calibration of instruments observing from the X-ray to the infrared spectral domains that include instrument-or mission-specific estimates of radiometric accuracies rounds off this review.

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“…A less-widely used technique for calibration of VUV and EUV spectrometers is the use of argon mini-arc 59 and high-current hollow cathode 60 secondary-standard radiometric sources. For example, Danzmann et al 60 have described a high current hollow cathode lamp which can be used as a radiometric source for the 13-60 nm region.…”

Section: Radiometric Calibrationmentioning

confidence: 99%

Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

Stratton¹,

Bitter²,

Hill³

et al. 2007

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Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given.Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

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Vacuum ultraviolet radiometry 3: The argon mini-arc as a new secondary standard of spectral radiance

Cited by 123 publications

References 6 publications

IMPROVED Co i log( gf ) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

IMPROVED Co i log( gf ) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

Spectroradiometry with space telescopes

Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

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