AAS 201st Meeting, January, 2003
Session 80. Gravitational Lenses
Poster, Wednesday, January 8, 2003, 9:20am-6:30pm, Exhibit Hall AB

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[80.04] Weak Lensing by Large-Scale Structure with the FIRST Radio Survey

T.-C. Chang (Columbia University), A. Refregier (CEA Saclay), D.J. Helfand (Columbia University), R.H. Becker (Lawrence Livermore National Laboratory), R.L. White (Space Telescope Science Institute)

Weak gravitational lensing produced by large-scale structure can be used to directly probe the mass inhomogeneities in the universe, through measurements of the induced coherent distortions of galaxy shapes. We measure this so-called ``cosmic shear'' with the FIRST radio survey, which contains about 320,000 resolved sources over 8000 square degrees of sky. The survey provides a unique resource for probes on large angular scales, and therefore the linear part of the projected lensing power spectrum. In order to extract the lensing signals from various contaminating sources, we have developed and applied a new method for interferometric data analysis and source shape measurements to the FIRST data. We expect our on-going experiment to yield a detection, or at least a tight upper limit, for the weak lensing power spectrum on 0.3-20 degree scales.


The author(s) of this abstract have provided an email address for comments about the abstract: tchang@astro.columbia.edu

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