I know that in ComCam DP1, there were known red (or infrared) leaks in the u and g bands. Are there any known red leaks for the DP2 datasets? In particular, in u or g?
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Hi @jgizis, thanks for your question. While others chime in, I wanted to point you to the DP2 known issues page which might be of interest.
Hi @jgizis, although excess transmission in the LSST g filter at wavelengths beyond the nominal bandpass (extending past 1100 nm) was revealed in testing, as far as I know this was only an appreciable issue with Data Preview 1 because LSSTComCam CCDs were operated at temperatures about 20 - 40°C warmer. Gloria linked you to the DP2 known issues page above, and it does not mention the g-band red lead like the DP1 page does, for this reason.
As Melissa mentioned the ‘r-leak’ in ComCam was caused by higher than designed operating temperature for the ComCam CCDs. At those temperatures a phonon-assist effect in Silicon further boosts the QE at the very red edge of the bandpass. NIR transmission in the g-band filter in ComCam was most evident via the observation of diffraction off the gates in bright stars, a sign of >1050nm light. To my knowledge such diffraction has not been observed in bright stars for LSSTCam observations.