Images

Images are where survey data begin. Before we can learn anything about galaxies, stars or the Universe, the images have to be reconstructed and understood: what their pixels mean, how they were blurred and sampled, and which imperfections they carry. Most of my work on images is for the Nancy Grace Roman Space Telescope, whose sharp but undersampled images need careful reconstruction before they can be used for weak gravitational lensing.

Roman's Wide Field Instrument detectors, a grid of eighteen squares, and its Coronagraph detector, shown against the starry sky with the full Moon for scale. — The fields of view of Roman's Wide Field Instrument and Coronagraph, compared with the full Moon, over an infrared image of the Fornax galaxy cluster. Credit: NASA's Goddard Space Flight Center; background, NASA/JPL-Caltech/UCLA (SVS 15096).

Image Reconstruction: Reconstructing well-sampled images with a controlled point spread function from a telescope's undersampled exposures, for the Nancy Grace Roman Space Telescope and beyond.
Image Analysis: The physical meaning of astronomical images: noise, detector effects and systematics, and images as discrete samples of continuous fields.
Extragalactic Astronomy: Nearby galaxies, distant galaxies and quasars, and strong gravitational lenses, to which I am glad to contribute my image processing expertise.

All my papers, with what I contributed to each, are on Publications. New to the topic? The Glossary explains the terms in plain language.