Flux calibration

The Hubble mid-UV echelle spectra extend blueward to 2130 A for hot stars, or to 2380 A or 2885 A for cooler ones. Redward they extend to 3120 A for faint stars, to 2885 A for bright hot stars, and to 3150 A for bright cool stars. These spectra are flux-calibrated, which fixes the mid-UV continuum normalization. 

No Net Flux/Zero Net Flux Calibration The most time intensive of all the in vivo microdialysis calibration methods is the method of no net flux (NNF), which is sometimes referred to as the method of zero net flux (ZNF). The NNF calibration method requires the analyte to be in a steady state. So, for healthy... 

Fig. 16 Calibration plot showing coverage of AI2O3 produced on Re(OOOl) (STM measured) from the Al doser flux (calibrated with AES).

Thermopile Radiation-measuring instrument consisting of a number of thermocouples connected together in series. Measures the incident total radiant flux (calibrated in microwatts). The irradiance is obtained by dividing the measured value by the effective sensitive receiving surface area. 

N. R. Keltner, B. L. Bainbridge, and J. V. Beck, Rectangular Heat Source on a Semi-Infinite Solid— An Analysis for a Thin Film Flux Calibration, 84-HT-46,1984. 

The calibration of the Long-Wave Spectrometer is discussed by Swinyard et al. (1996) and by Burgdorf etal. (1998). A description of the Short-Wave Spectrometer is given by de Graauw etal. (1996). Flux calibration has been discussed by Schaeidt et al. (1996) and wavelength calibration by Valentijn et al. (1996). 

In addition to irradiation of indium foils for measuring flux distributions in (6) above, it is desired that we irradiate a gold foil for absolute flux calibration at one point in the spectrums. Is it now necessary to correct for flux depression ... 

Together with our flux calibration for this observation, the measured NEFD in this image is 42 mJy mtn arcsec. This is worse than our best measured system performance of 23.5 mJymin f arcsec because our sensitivity (as measured by our standard star flux calibrations) was reduced due to poor sky transmission. 

The linear relation between the PSL signal and neutron fluence was established to exist over three decades up to 6. lO cm. The IP-ND can be used as fast and efficient neutron monitors at rather low neutron fluxes. However, for neutron dosimetry individual IP-ND must be calibrated individually since their sensitiviy can differ from one plate to another. In Gd/film based direct NR the film fog below the exposure dose of about 8.10 cm is the limiting factor. 

Previous studies of the interaction of energetic particles with suri ces have made it clear that under nearly all conditions the majority of atoms or molecules removed from a surface are neutral, rather than charged. This means that the chained component can have large relative fluctuations (orders of magnitude) depending on the local chemical matrix. Calibration with standards for surfaces is difficult and for interfaces is nearly impossible. Therefore, for quantification ease, the majority neutral component of the departing flux must be sampled, and this requires some type of ionization above the sample, often referred to as post-ionization. SALI uses effi-... 

The advanced control room uses fiber optics, microprocessors, and digital monitoring and control. This includes self-testing, automatic calibration, user interactive from panels, full multiplex, standardization of the man-machine interface, common circuit cards, and wide-range flux monitors to eliminate range switching on startup. 

Requirements of Standards. Standards used In the calibration of mlcrospectrofluorometrlc Instrumentation must meet more stringent requirements than those used In macromeasurements. The effect of Increased excitation flux as well as spatial effects under magnification make many macromeasurement standards unsatisfactory for micromeasurements. Following are some of the requirements for fluorescence standards that are strongly Influenced by a change from the macro- to the micro-environment. 

The complete data series is used to calculate the temperature response, but only certain parts of the experimental data are used to calculate the error. An example of a calibration run is given in Figure 53, the final calibrated TRNSYS model run is shown in Figure 54. Using the first part of the data (with constant heat flux) an estimate of ground thermal conductivity of 2.15 was obtained. Yavatzturk s method yielded an estimate of 2.18, while the estimate obtained with the TRNSYS parameter estimation method was 2.10. 

Plotting the errors for all individual data points (Figure 56) for the different calibration runs it is clear that largest errors are associated with periods of transient heat flux. Moreover, errors during the period with heat extraction (1—40 h and 1-80 h), increase with time. 

Calibration to absolute intensity means that the scattered intensity is normalized with respect to both the photon flux in the primary beam and the irradiated volume V. Thereafter the scattering intensity is either expressed in terms of electron density or in terms of a scattering length density. Both definitions are related to each other by Compton s classical electron radius. 

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