There is read noise from downstream electronics converting photons to electrons, but the "shot noise" is a property of the photon stream and will be present reg

There is read noise from downstream electronics converting photons to electrons, but the "shot noise" is a property of the photon stream and will be present regardless of how much we improve the electronics. Cooling the detector won't help there. https://en.wikipedia.org/wiki/Shot_noise#Optics https://en.wikipedia.org/wiki/Shot_noise#Optics