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LensMEM: A Gravitational Lens Inversion Algorithm Using the Maximum Entropy Method

S. Wallington·C. S. Kochanek·R. Narayan
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Abstract

We present a new algorithm for inverting poorly resolved gravitational lens systems using the maximum entropy method (MEM). We test the method with simulations and then apply it to an 8 GHz VLA map of the radio ring lens MG1654+134. We model the lens as a singular isothermal sphere embedded in an external shear field and find the critical radius of the lens is $b=0\parcs9820$, the dimensionless shear is $γ=0.0771$, and the position angle of the shear is $θ=100\pdeg8$. These results are consistent with the results obtained by Kochanek (1995) using a complementary inversion algorithm based on Clean.

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S. Wallington, C. S. Kochanek, R. Narayan. 1995-11-28. LensMEM: A Gravitational Lens Inversion Algorithm Using the Maximum Entropy Method. https://doi.org/10.1086/177401

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