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Dead Time

Dead-time corrections are important (i.e., are greater than 1%) only for line emission above 30 count s-1 integrated over the line, or > 4 count pixel-1s-1 at the peak for a line of 3 Å full-width at half-maximum (FWHM), or > 3 count pixel-1s-1 at the peak of a 6 Å FWHM line. Continuum emission limits are lower, with corrections important only at rates exceeding 1 count pixel-1s-1. Since few HUT targets exceed these rates and since the Monte-Carlo detector model is computationally expensive, dead-time corrections are not routinely calculated for all HUT spectra in the reduction process. When appropriate, these calculations must be done off-line separately for each observation.