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5. What’s the meaning of “group gap” or “dropframes” in the JWST NIR detectors?

  • these are frames between groups that are sampled but not included in the group average

6. What is a reset?

  • stops the pixels from accumulating charge and resets them to the bias level

7. What is an integration?8. What is an exposure?

  • a set of groups starting with the first group after a reset and ending with either the last group before a reset (NIR) or the last read-reset group (MIRI)

8. What is an exposure?

  • a set of identical integrations that are separated by only a constant number of resets (nominally 1)

9. Suppose you have data from a CCD and from a JWST detector. They both reach the saturation level in one-half of the total integration time. Can you describe what the main difference is? Can you recover information in the saturated pixels?

  • You can recover info in saturated pixel in JW detector but not from CCD because the charge/signal as a function of time is recorded in JW detector.

10. What will be the impact of a cosmic ray in a JWST integration? Can information be recovered?

  • impact is a jump in signal as function of time; yes info can be recovered.

11. a) What is the practical difference between a MIRI SLOW mode exposure and a NIR exposure with NFRAMES=8? b) Which has a higher data rate: a single MIRI Si:As

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