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37.5 Calibration Quality Files

calhrs reads the raw data quality files, operates on the data using the quality flags as a discriminate, and flags the appropriate data values in the output quality files. Fill data are ignored. Reed-Solomon flagged data are calibrated, but is flagged as suspect in the output quality files.

The initial error in the data is assumed to be Poisson-limited. The error is propagated mathematically through the calibration process. The propagated statistical error file (.c2h) contains a measure of the statistical errors of the original data values; this file is calibrated in lock-step with the science data files.

The flux data quality file (.cqh) flags bad pixel values in the calibrated flux and propagated statistical error files.

Special diodes data quality files (.c4h) flags bad pixel values in the calibrated special diodes file (.c3h). Good pixel values are identified by a zero value.



Calibrated Data Quality Flags

Flag Value

Description

Category 1: Data not useful -data values set to zero

800

Data filled

400

Dead or disabled channel

300

Severe saturation (uncertainty >50%)

Category 2: Data uncertain-uncertainty not indicated in error computation

190

Large saturation correction (uncertainty > 20%)

180

Photocathode blemish (deep)

150

Photocathode blemish (medium)

140

Photocathode blemish (small)

130

Moderate saturation correction (uncertainty >5%)

100

Reed-Solomon decoding error

Category 3: Data uncertain-uncertainty indicated in propagated error file

30

Dead diode contributed to comb-added data point



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