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arXiv · 1209.0903

Femto-lensing due to a Cosmic String

Chul-Moon Yoo·Ryo Saito·Yuuiti Sendouda·Keitaro Takahashi·Daisuke Yamauchi
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Abstract

We consider the femto-lensing due to a cosmic string. If a cosmic string with the deficit angle $\Delta\sim 100$ [femto-arcsec] $\sim10^{-18}$ [rad] exists around the line of sight to a gamma-ray burst, we may observe characteristic interference patterns caused by gravitational lensing in the energy spectrum of the gamma-ray burst. This "femto-lensing" event was first proposed as a tool to probe small mass primordial black holes. In this paper, we propose use of the femto-lensing to probe cosmic strings with extremely small tension. Observability conditions and the event rate are discussed. Differences between the cases of a point mass and a cosmic string are presented.

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Chul-Moon Yoo, Ryo Saito, Yuuiti Sendouda, Keitaro Takahashi, Daisuke Yamauchi. 2012-09-05. Femto-lensing due to a Cosmic String. https://doi.org/10.1093/ptep/pts045

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