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Gravitational microlensing of gamma-ray blazars

Diego F. Torres·Gustavo E. Romero·Ernesto F. Eiroa·Joachim Wambsganss·M. E. Pessah
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Abstract

We present a detailed study of the effects of gravitational microlensing on compact and distant $γ$-ray blazars. These objects have $γ$-ray emitting regions which are small enough as to be affected by microlensing effects produced by stars lying in intermediate galaxies. We analyze the temporal evolution of the gamma-ray magnification for sources moving in a caustic pattern field, where the combined effects of thousands of stars are taken into account using a numerical technique. We propose that some of the unidentified $γ$-ray sources (particularly some of those lying at high galactic latitude whose gamma-ray statistical properties are very similar to detected $γ$-ray blazars) are indeed the result of gravitational lensing magnification of background undetected Active Galactic Nuclei (AGNs).

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Diego F. Torres, Gustavo E. Romero, Ernesto F. Eiroa, Joachim Wambsganss, M. E. Pessah. 2002-05-24. Gravitational microlensing of gamma-ray blazars. https://doi.org/10.1046/j.1365-8711.2003.06219.x

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