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Verification of a prediction made by Prof. S. Rahvar and his collaborators

A prediction made by our Prof. S. Rahvar and his collaborators [link] regarding the possibility of observing self-lensing binary star systems with space-based telescopes has been just recently verified by the analysis of data from the Kepler spacecraft [see: link].

Gravitational lensing is the observational effect of bending of light in curved-space time. This phenomenon has been observed at cosmological and galactic scales, and nowadays it has turned to be a useful tool for astrophysical and cosmological studies. The possibility of self-lensing in a binary system where one of the companions is a main sequence star and the other is a white dwarf or a black hole has been proposed by Maeder in 1973. Detailed analysis for possibility of observing this phenomenon with space-based telescopes in recent years has been done by Sahu (2003), Gould (1995), Rahvar, Mehrabi, and Dominik (2011), and Mao (2012). Recently, Kruse and Agol reported the discovery of this phenomenon in a paper published in Science. Their analysis of light curves of stars from the Kepler spacecraft found a candidate with the signal of self-lensing effect. This discovery will open up a new window in studying compact objects as white dwarfs and black-holes orbiting in binary systems.

We are happy of this news, and congratulate Prof. Rahvar and his colleague for this great prediction.