摘要: Removing optical and atmospheric blur from galaxy images significantly
improves galaxy shape measurements for weak gravitational lensing and galaxy
evolution studies. This ill-posed linear inverse problem is usually solved with
deconvolution algorithms enhanced by regularisation priors or deep learning. We
introduce a so-called "physics-based deep learning" approach to the Point
Spread Function (PSF) deconvolution problem in galaxy surveys. We apply
algorithm unrolling and the Plug-and-Play technique to the Alternating
Direction Method of Multipliers (ADMM), in which a neural network learns
appropriate hyperparameters and denoising priors from simulated galaxy images.
We characterise the time-performance trade-off of several methods for galaxies
of differing brightness levels as well as our method's robustness to systematic
PSF errors and ablations. We show an improvement in reduced shear ellipticity
error of 38.6% (SNR=20)/45.0% (SNR=200) compared to classic methods and 7.4%
(SNR=20)/33.2% (SNR=200) compared to modern methods.