The true nature of CSL-1

TL;DR

The paper clarifies that CSL-1, initially thought to be a cosmic string lensing event, is actually a pair of interacting elliptical galaxies, resolving a prior cosmic string hypothesis.

Contribution

It provides observational evidence disproving the cosmic string lensing interpretation of CSL-1, confirming its nature as a galaxy pair.

Findings

CSL-1 is a pair of interacting elliptical galaxies

No evidence of gravitational lensing by a cosmic string

High-resolution imaging refutes previous cosmic string hypothesis

Abstract

On January 12 2006, the Hubble Space Telescope observed the peculiar double extragalactic object CSL-1, suspected to be the result of gravitational lensing by a cosmic string. The high resolution image shows that the object is actually a pair of interacting giant elliptical galaxies. In spite of the weird similarities of the energy and light distributions and of the radial velocities of the two components, CSL-1 is not the lensing of an elliptical galaxy by a cosmic string.