Cryogenic absolute radiometers as laboratory irradiance standards, remote sensing detectors, and pyroheliometers

Foukal, P.; Hoyt, Clifford; Kochling, H.; Miller, Peter J.

doi:10.1364/ao.29.000988

Cited by 62 publications

(42 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The temperature increase of an irradiated cavity cooled to liquid helium temperatures is compared by a null method with the temperature increase caused by deposition of accurately measured electrical power into an equivalent cavity. Although corrections for reflections, scattering and diffraction must be made, cryogenic radiometers are accepted as the most accurate radiometric standards (Fox and Martin 1990;Foukal et al 1990;Hoyt and Foukal 1991;Quinn and Martin 1991a, b).…”

Section: Primary Radiometric Standardsmentioning

confidence: 99%

Spectroradiometry with space telescopes

Pauluhn

Huber

Smith

et al. 2015

Astron Astrophys Rev

View full text Add to dashboard Cite

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.

show abstract

Section: Primary Radiometric Standardsmentioning

confidence: 99%

Spectroradiometry with space telescopes

Pauluhn

Huber

Smith

et al. 2015

Astron Astrophys Rev

View full text Add to dashboard Cite

show abstract

“…The radiance on the integrating sphere was calibrated using the TACR 9 . The TACR is a cryogenically cooled active cavity radiometer that works on the principle of electrical substitution heating 10 . The TACR has been fitted with the same fore-optics as the CERES flight instruments to minimize the errors caused by mismatched field of views and aperture areas.…”

Section: Radiometric Calibration Facility (Rcf)mentioning

confidence: 99%

Pre-launch characterization of spectral response functions for the Clouds and Earth's Radiant Energy System (CERES) instrument sensors

Shankar

Thomas

Priestley

2010

Earth Observing Systems XV

View full text Add to dashboard Cite

The Clouds and Earth's Radiant Energy System (CERES) uses four instruments onboard two spacecraft to make measurements of the earth's reflected shortwave and emitted longwave radiation, which constitute two components of earth radiation budget. Flight Models 1 and 2 (FM1, FM2) are onboard the TERRA spacecraft and Flight Models 3 and 4 (FM3, FM4) are onboard the AQUA spacecraft. The measurements are made using three radiometric sensor channels on each instrument-shortwave channel (0.3-5 microns), window channel (8-12 microns) and total channel (0.3-200 microns). This paper describes the process of obtaining the estimates of the spectral response functions of the three sensor channels using pre-launch measurements. The shortwave spectral response function (0.3-2 microns) for the shortwave channel as well as the shortwave region of the total channel is obtained through measurements of the components in the optical path. The longwave responses (>2 microns) are obtained using a Fourier Transform Spectrometer (FTS) system. The CERES sensors as well as a reference detector, which is used to account for any measurement or background noise in the system, acquire measurements of the FTS. By the use of various sources and beam-splitters in the spectrometer, the entire spectral range of the broadband total channel is covered. The spectral estimates are obtained in smaller, overlapping bands, which are then tied together appropriately to obtain the end-to-end spectral response function for each of the sensors for all CERES instruments.

show abstract

“…This ECPR radiometer is traceable to our absolute cryogenic radiometer [7]. Four tunable laser diodes covering the range between 1250-1650 nm were used in a calibration setup similar to the one used in reference [12]. At 850 nm a multimode laser diode has been used.…”

Section: 3-spatial Non-uniformity Of Responsementioning

confidence: 99%