Search for Cosmic Strings in the COSMOS Survey
  We search the COSMOS survey for pairs of galaxies consistent with the
gravitational lensing signature of a cosmic string. The COSMOS survey imaged
1.64 square degrees using the Advanced Camera for Surveys (ACS) aboard the
Hubble Space Telescope (HST). Our technique includes estimates of the
efficiency for finding the lensed galaxy pair. We find no evidence for cosmic
strings with a mass per unit length of G mu/c^2 < 3.0E-7 out to redshifts
greater than 0.6 and set 95% upper limits. This corresponds to a global 95%
upper limit of Omega_string<0.0028.
