Effects of cosmic ray removal on the accumulating signal of the infrared spectrograph

摘要

During the in-orbit checkout phase of the Infrared Spectrograph on board The Spitzer Telescope, it was found that the noise of the spectrograph's arrays was correlated with the number of cosmic ray hits. Our analysis reveals that the cause of that effect is most likely due to the algorithms used to correct cosmic ray hits on dark pixels. We also found that the noise characteristics of the pixels that have an illumination that is lower than 1/10 of the full well is artificially raised by the cosmic ray correction by a factor of about 10% if 1% of the pixels are affected by cosmic rays.