The Detection of Outliers in Nondestructive Integrations with the Generalized Extreme Studentized Deviate Test

The identification of outliers in nondestructive integrations represents an important step in the routine processing of on-orbit or ground observations and in providing data of the highest quality to the observer. We present the Generalized Extreme Studentized Deviate (ESD) Test for multiple outliers and apply it to the iden- tification of cosmic ray hits in simulated integrations and in ground laboratory observations collected with a James Webb Space Telescope (JWST) near-IR detector. The completeness ratio and fraction of false detections of the simulated cosmic-ray impacts are characterized for a range of parameters expected in real-world observations. Ran- dom Telegraph Noise (RTN) pixels, which are intrinsically variable, are also successfully identified with this test. The algorithm of this versatile statistical test is straightforward to implement and can serve to flag and mask bad or variable pixels in automated data calibration pipelines.