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arXiv · 1911.08327

Eliminating artefacts in Polarimetric Images using Deep Learning

Dhruv Paranjpye·Ashish Mahabal·A. N. Ramaprakash·Gina Panopoulou·Kieran Cleary·Anthony Readhead·Dmitry Blinov·Kostas Tassis
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Abstract

Polarization measurements done using Imaging Polarimeters such as the Robotic Polarimeter are very sensitive to the presence of artefacts in images. Artefacts can range from internal reflections in a telescope to satellite trails that could contaminate an area of interest in the image. With the advent of wide-field polarimetry surveys, it is imperative to develop methods that automatically flag artefacts in images. In this paper, we implement a Convolutional Neural Network to identify the most dominant artefacts in the images. We find that our model can successfully classify sources with 98\% true positive and 97\% true negative rates. Such models, combined with transfer learning, will give us a running start in artefact elimination for near-future surveys like WALOP.

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Dhruv Paranjpye, Ashish Mahabal, A. N. Ramaprakash, Gina Panopoulou, Kieran Cleary, Anthony Readhead, Dmitry Blinov, Kostas Tassis. 2019-11-19. Eliminating artefacts in Polarimetric Images using Deep Learning. https://doi.org/10.1093/mnras%2Fstz3250

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