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arXiv · 0903.0620

A Fast New Public Code for Computing Photon Orbits in a Kerr Spacetime

Jason Dexter·Eric Agol
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Abstract

Relativistic radiative transfer problems require the calculation of photon trajectories in curved spacetime. We present a novel technique for rapid and accurate calculation of null geodesics in the Kerr metric. The equations of motion from the Hamilton-Jacobi equation are reduced directly to Carlson's elliptic integrals, simplifying algebraic manipulations and allowing all coordinates to be computed semi-analytically for the first time. We discuss the method, its implementation in a freely available FORTRAN code, and its application to toy problems from the literature.

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Jason Dexter, Eric Agol. 2009-03-03. A Fast New Public Code for Computing Photon Orbits in a Kerr Spacetime. https://doi.org/10.1088/0004-637x%2F696%2F2%2F1616

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