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These calibrations exist in the STScI Calibration Data Base, and are accessible with the STSDAS SYNPHOT package or with the XCAL software. The XCAL and SYNPHOT Users Guides should be consulted for further details. We include here a sufficient calibration for exposure planning.
In Table 6.1
The mean wavelength is defined in Schneider, Gunn, and Hoessel Ap. J., 264, 337 (1983)
This rather unconventional definition has the property that the correspondingly defined mean frequency is just
. It is in some sense halfway between the conventional frequency mean and the wavelength mean. The pivot wavelength is defined as
The effective dimensionless Gaussian width is defined implicitly by
where the integration limits eliminate unrealistic contributions from imperfect blocking far from the bandpass. The effective width of the bandpass is
The final two columns in Table 6.1
Table 6.1: System Efficiencies and Zeropoints.
Table 6.2: AB_nu as a Function of Wavelength.