Multipole Expansion Model in Gravitational Lensing
نویسندگان
چکیده
Non-transparent models of multipole expansion model and two pointmass model are analyzed from the catastrophe theory. Singularity behaviours of 2n-pole moments are discussed. We apply these models to triple quasar PG1115+080 and compare with the typical transparent model, softened power law spheroids. Multipole expansion model gives the best fit among them.
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