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arXiv · 2010.03762

Peculiar Velocity Estimation from Kinetic SZ Effect using Deep Neural Networks

Yuyu Wang·Nesar Ramachandra·Edgar M. Salazar-Canizales·Hume A. Feldman·Richard Watkins·Klaus Dolag
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Abstract

The Sunyaev-Zel'dolvich (SZ) effect is expected to be instrumental in measuring velocities of distant clusters in near future telescope surveys. We simplify the calculation of peculiar velocities of galaxy clusters using deep learning frameworks trained on numerical simulations to avoid the estimation of the optical depth. The image of distorted photon backgrounds are generated for idealized observations using one of the largest cosmological hydrodynamical simulations, the Magneticum simulations. The model is tested to be capable peculiar velocities from future kinetic SZ observations under different noise conditions. The deep learning algorithm displays robustness in estimating peculiar velocities from kinetic SZ effect by an improvement in accuracy of about 17% compared to the analytical approach.

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Yuyu Wang, Nesar Ramachandra, Edgar M. Salazar-Canizales, Hume A. Feldman, Richard Watkins, Klaus Dolag. 2020-10-08. Peculiar Velocity Estimation from Kinetic SZ Effect using Deep Neural Networks. https://doi.org/10.1093/mnras%2Fstab1715

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