Anomalous Fluctuations in Observations of Q0957+561 A,B: Smoking Gun of a Cosmic String?

R. Schild; I Masnyak; B. Hnatyk; V. Zhdanov

doi:10.1051/0004-6361:20040274

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Anomalous Fluctuations in Observations of Q0957+561 A,B: Smoking Gun of a Cosmic String?

R. Schild·I Masnyak·B. Hnatyk·V. Zhdanov

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Abstract

We report the detection of anomalous brightness fluctuations in the multiple image Q0957+561 A,B gravitational lens system, and consider whether such anomalies have a plausible interpretation within the framework of cosmic string theory. We study a simple model of gravitational lensing by an asymmetrical rotating string. An explicit form of the lens equation is obtained and approximate relations for magnification are derived. We show that such a model with typical parameters of the GUT string can quantitatively reproduce the observed pattern of brightness fluctuations. On the other hand, explanation involving a binary star system as an alternative cause requires an unacceptably large massive object at a small distance. We also discuss possible observational manifestations of cosmic strings within our lens model.

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R. Schild, I Masnyak, B. Hnatyk, V. Zhdanov. 2004-06-18. Anomalous Fluctuations in Observations of Q0957+561 A,B: Smoking Gun of a Cosmic String?. https://doi.org/10.1051/0004-6361%3A20040274

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