Questions tagged [charge-coupled-devices]

Questions about CCD-sensors, i.e. light-sensitive electronic devices based on the internal photoelectric effect.

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What is the probability that a photon that enters the aperture is registered?

If I want to derive the probability that a photon that enters the aperture of a telescope is detected, how do I do that? This should be closely related to the quantum efficiency of a telescope, but ...
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2 votes
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What was the first use of time-delay integration in Astronomy? Are there instances before GAIA?

In the context of GAIA, time-delay integration is the clocking of a CCD's charge shift register at a frequency such that it matches the linear speed across the focal plane of the actual image. So even ...
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Calibrating raw photometric measurements

So I have a photometry data sourced from Solar Mass Ejection Imager's (SMEI) server as an ‘add-on data’ for my point source of interest (a variable star) with a 104 minute cadence. However, it’s not ...
  • 105
3 votes
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Why wasn't CHEOPS data taken during passage through the South Atlantic Anomaly downlinked in this case, resulting in gaps in photometry?

Section 4.1.2. CHEOPS in Six transiting planets and a chain of Laplace resonances in TOI-178 says Due to the low-Earth orbit of CHEOPS, the spacecraft-target line of sight was interrupted by Earth ...
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3 votes
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How often are electron-multiplying CCDs used in telescope focal planes? Will Nancy Grace Roman be the first use in a space telescope?

Section I. of The Wide Field Infrared Survey Telescope: 100 Hubbles for the 2020s says: Table 1 summarizes the WFIRST instrument suite, and Figure 1 presents the effective area of the Wide Field ...
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