Calibration Access and Data Handbook

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The task returns the X-ray transmission factor for the suspected contamination layer. For each energy bin the transmission is obtained by interpolating the between transmission values stored for neighbouring energy points. Not yet implemented

By invoking the time, the predicted depth of contamination layer is first calculated from some TBD coefficients, stored in a depth extension. Ad interim we assume a linear growth from a reference point of form:

Depth = Growth  .  (Time - Reference Time)

The attenuation extension then has linear attenuation coefficients versus energy appropriate for the witches brew building up on the CCDs. From the depth value, a transmission factor is thus obtained.

Michael Smith 2011-09-20