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arXiv · 1501.03921

Deflection of light by the field of a binary system

Nahid Ahmadi·Zainab Sedaghatmanesh
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Abstract

We examine the motion of a photon in the gravitational field of a binary system. The equations of motion are geodesic equations in a Schwarzchild background with a tidal force. We specialize the equations to that of an edge-on binary and use the method of osculating elements to integrate them. This work helps to identify a binary system through the gravitational light deflection of one member in the gravitational field of the other member. It is found that the effects of the companion body on a photon passing the edge of the star can be potentially detected by astrometric satellites with $μ$as precision, if the ratio of the Schwarzchid radius to the star radius, $\frac{Gm}{c^2 R}\geq 10^{-5}$. Two different cumulative effects on the photon path are identified.

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Nahid Ahmadi, Zainab Sedaghatmanesh. 2015-04-27. Deflection of light by the field of a binary system. https://doi.org/10.1088/0264-9381%2F32%2F23%2F235015

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