11.1.6 Application of Calibrations and Corrections

It is important to note that, as implemented in the image processing software, the interpolated inverse sensitivity values, time- and temperature-dependent sensitivity corrections, effective exposure time normalization, and any overall gain correction factor (for non-standard exposure or read gain or LWR UVC voltage settings) are computed as independent correction factors and then all applied simultaneously to the net flux and sigma spectra to result in fully calibrated and corrected spectra in absolute flux units. The net flux spectrum (in FN units), as determined by SWET, that is retained in the low-dispersion extracted spectrum does not have any of these correction factors applied to it. The calibrations and corrections are applied as follows:

$$F_{calib} = FN_{\lambda} \times S_{\lambda}^{-1} \times gain \times R_{T} / R_{t} / t_{eff}$$

$$\sigma_{calib} = \sigma_{FN_{\lambda}} \times S_{\lambda}^{-1} \times gain \times R_{T} / R_{t} / t_{eff}$$

where $S_{\lambda}^{-1}$ is the inverse sensitivity (including any necessary S/L or T/L response corrections), gain is the cumulative UVC voltage and gain correction factor (if necessary), R_t and R_T are the time- and temperature-dependent sensitivity correction factors, respectively, and t_eff is the effective exposure time. The values for $S_{\lambda}^{-1}$ and R_t are evaluated at the wavelength of each pixel through quadratic and nearest neighbor interpolation, respectively, of their tabulated values. The resulting absolutely calibrated units are ergs/cm²/Å/sec.