Developing the first astronomical and quantum imaging instrument using the Smart Skipper-CCD technique

Abstract: Cosmic surveys aim to understand the fundamental physics governing dark energy and dark matter, which together comprise 95% of the Universe. This proposal seeks to develop technology and scientific forecasts for next-generation cosmic surveys probing the ‘dark sector’. Our specific aims are: (1) to develop faster readout strategies for low-noise Skipper CCDs, (2) characterize the optical performance of these detectors for use in quantum imaging applications and cosmic surveys, (3) to demonstrate the first implementation of Skipper CCDs on a prototype astronomical instrument, and (4) to assess the sensitivity of future cosmic surveys to fundamental properties of dark matter. The non-destructive charge sensing capability of the Skipper CCD (compared to the destructive readout of standard CCD [1]) allows to take several measurements of the pixel charge and average them out to get a final value with a smaller error. The final error, given by the readout noise (RN), has an inverse relationship with the number of measurements per pixel [2, 3]. Values of 0.1 e- (5-sigma discrimination of single photons) can be achieved for 1000 samples with total readout times in the order of milliseconds. We propose to significantly reduce the readout time by means of an optimization of the number of samples per pixel based on the on-line information from the first measurements of the charge of the pixel. This optimization is implemented on high-speed digital processing hardware. For spectroscopy applications, the uncertainty in large charge packets will be dominated by the shot noise from photon absorption so the readout noise requirements can be relaxed (therefore less readout time needed). The technique dramatically reduces the readout time of the Skipper CCD and makes it suitable applications in astronomy and quantum optics. We propose to develop the first instrument for astronomy and quantum imaging applications that uses the smart skipper capability