am a member of the Deep Lens Survey collaboration (Tony Tyson, PI, at
Bell Labs). The project involves making an ultra-deep multiband
optical survey of seven 4 square degree fields. The main goal of
the survey is to produce unbiased maps of the large-scale structure
of the mass distribution beyond the local universe. The shear of the images
of distant galaxies induced by the mass of
foreground structures will be measured. These weak-lensing observations
are sensitive to all forms of clumped mass and will yield
unbiased mass maps with resolution of one arcmin in the plane of
the sky (about 120 kpc/h at z = 0.2), in multiple redshift ranges.
These maps will measure for the first time the evolution in large scale
structure from z=1 to the present epoch, and will provide a test of the
current theories of structure formation. These
observations will directly constrain the clustering properties of
matter, most notably Omega_matter and Omega_Lambda, and, when
compared with the results from microwave background anisotropy missions,
will test the basic theory of structure formation via gravitational
instability. Further details can be found at the
Deep Lens Survey homepage.
A reference to the first measurement of the "cosmic shear" described here
was reported by Wittman et al. (Nature 404 (2000) pp 143-148).
Gravitational lensing is one component of the nuclear,
particle and particle-astrophysics programs of the
New Mexico Center for Particle Physics in the
Department of Physics
and Astronomy at the
University of New Mexico, Albuquerque, NM
87131, USA.
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