Absolute radiometric characterization of the transfer radiometer unit of RASTA in the UV, VIS and NIR spectral range

The German Aerospace Centre (DLR) is operating the Calibration Home Base (CHB) as a facility for the radiometric calibration of airborne hyperspectral sensors and field spectrometers, the calibration concept relying on the application of both absolutely calibrated source- and detector-based radiometric transfer standards. Following this concept, DLR has designed a new and dedicated radiance standard (RASTA).To provide a source-based SI traceability to the CHB facility, RASTA has been recently calibrated at the Physikalisch-Technische Bundesanstalt (PTB). To provide redundancy to the source-based calibration and to take advantage of the superior stability of detector-based radiometric transfer standards, the RASTA design includes a multiple detector unit, the so-called transfer radiometer. This transfer radiometer is built up of five individual filter radiometers (FRs), each consisting of a detector, a dedicated amplifier and an associated temperature controller. Three of these FRs use silicon photodiodes as detectors and coloured optical glass filters as wavelength selecting elements with centre wavelengths at 400 nm, 550 nm and 850 nm. The remaining two FRs are of broad-band design without any filters, applying a standard-type and a long-wavelength-type InGaAs photodiode for covering the wavelength range from 850 nm to 1.7 µm and 850 nm to 2.5 µm, respectively. The measurement of the spectral irradiance responsivity of each of these FRs was performed at the spectral comparator facility of PTB. In the wavelength range from 250 nm to 1.7 µm, this was accomplished by comparison with absolutely calibrated transfer detectors, traceable to the primary detector standard, the cryogenic radiometer. In the wavelength range from 1.7 µm to 2.5 µm a relative calibration was done by applying a thermopile-detector with a previously characterized, spectrally flat absorbing layer. The instrumentation, the comparison procedure and the calibration results including a detailed uncertainty analysis will be presented

SOLAR/SOLSPEC: Scientific Objectives, Instrument Performance and Its Absolute Calibration Using a Blackbody as Primary Standard Source

International audienceSOLAR is a set of three solar instruments measuring the total and spectral absolute irradiance from 16 nm to 3080 nm for solar, atmospheric and climatology physics. It is an external payload for the COLUMBUS laboratory launched on 7 February 2008. The mission’s primary objective is the measurement of the solar irradiance with the highest possible accuracy, and its variability using the following instruments: SOL-ACES (SOLar Auto-Calibrating EUV/UV Spectrophotometers) consists of four grazing incidence planar gratings measuring from 16 nm to 220 nm; SOLSPEC (SOLar SPECtrum) consists of three double gratings spectrometers, covering the range 165 nm to 3080 nm; and SOVIM (SOlar Variability Irradiance Monitor) is combining two types of absolute radiometers and three-channel filter – radiometers. SOLSPEC and SOL-ACES have been calibrated by primary standard radiation sources of the Physikalisch-Technische Bundesanstalt (PTB). Below we describe SOLSPEC, and its performance

Methodologies and uncertainty estimates for T - T 90measurements over the temperature range from 430 K to 1358 K under the auspices of the EMPIR InK2 project

18 pags., 15 figs., 16 tabs.We report new developments in instrumentation and techniques for both acoustic (speed of sound) and radiometric primary thermometry methods. These include both new cylindrical resonators for extending acoustic gas thermometry to higher temperatures and absolute radiation thermometers incorporating InGaAs detectors to extend primary radiometry to lower temperatures than can be achieved using Si-detector based instruments. These new approaches have been established in order to determine the difference between thermodynamic temperature, T, and the International Temperature Scale of 1990 (the ITS-90), T90, over the temperature range from 430 K to 1358 K as part of the three-year EMPIR project `Implementing the new kelvin 2¿ (InK2). This paper describes the facilities and measurement methodologies for measuring T¿T90 at each of the different institutes, along with an assessment of the target uncertainties. The work is ongoing, but we anticipate that the results of these measurements will ultimately be pooled to provide consensus values of T¿T90 with associated estimated uncertainties. These consensus values will initially feed into the technical annex of the mise en pratique for the definition of the kelvin (MeP-K-19) and, if required, will be used to help to provide a foundation for any future temperature scale.This work has received funding from the EMPIR programme co-financed by the Participating States and from the European Union’s Horizon 2020 R&I programme through the InK2 project. NIM’s research was supported by the National Key R&D Program of China (number 2016YFF0200101

Third Universal Definition of Myocardial Infarction

Cardiolog