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11.1.4 Time-Dependent Degradation Correction

The sensitivity of the SEC Vidicon camera is known to degrade with time, hence the need for a method to correct for this loss. One of the fundamental requirements of the IUE Final Archive is that the dataset be fully intercomparable. The sensitivity degradation correction is essential in satisfying this requirement and allowing full utilization of the remarkably long timeline of IUE observations. The broad-band sensitivity analysis (Garhart 1992a) that monitors the degradation effects on the optical coatings of the camera caused by exposure to radiation is of insufficient resolution to provide a proper correction algorithm. The analysis described herein was motivated as a result of this concern.


Karen Levay