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Defocusing gravitational microlensing

Salvatore Capozziello·Ruggiero de Ritis·Vladimir Mank'o·Alma Angela Marino·Giuseppe Marmo
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Abstract

We introduce the notion of defocusing gravitational lens considering a MACHO located behind a light source with respect to an observer. The consequence of defocusing effect is a temporal variability of star luminosity which produces a gap instead of a peak as tell--tale signature in the light curve. General theory of (de)focusing rays (geodesics) in a gravitational field is presented. Furthermore, we give estimations of the mass of the lens and the optical depth connected to such a phenomenon.

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Salvatore Capozziello, Ruggiero de Ritis, Vladimir Mank'o, Alma Angela Marino, Giuseppe Marmo. 1996-10-21. Defocusing gravitational microlensing. https://doi.org/10.1088/0031-8949%2F56%2F2%2F007

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