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arXiv · 2308.16452

Imaging with a gravitational lens: the geometric view

Viktor T. Toth
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Abstract

We investigate imaging point sources with a monopole gravitational lens, such as the Solar Gravitational Lens in the geometric optics limit. We compute the light amplification of the lens used in conjunction with a telescope featuring a circular aperture that is placed in the focal region of the lens, compared to the amount of light collected by the same telescope unaided by a gravitational lens. We recover an averaged point-spread function that is in robust agreement with a wave-theoretical description of the lens, and can be used in practical calculations or simulations.

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Viktor T. Toth. 2023-08-31. Imaging with a gravitational lens: the geometric view. https://doi.org/10.1093/mnras%2Fstad3293

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