The primary goal of the survey is to use gravitational lensing to study the amount of matter in the Universe, the clumping of the matter, and the evolution of the clumping.  This will be used to help determine what type of Universe we live in, its beginning and its ultimate fate.   The two major projects involve measurement of the amplitude of the gravitational lensing signal from Large Scale Structure, and the measurement of the galaxy cluster mass function at different redshifts.  In addition, the images will be used for a wide range of projects studying the evolution of galaxies, the oldest stars in our galaxy, and distant quasars among others.  As befits a survey-type program, the data is being made publicly available as the imaging is completed.


Finally, we are also studying how the sky varies in time. Because the observations of the separate regions take a large amount of telescope time, the observations can be spaced in time with intervals of minutes, days, months and years.  Each observation can then be compared with the previous observations to see what has changed. Each run, we produce catalogs of asteroids, variable stars, and supernovae, and we are in a good position to observe rare phenomena such as Gamma-ray burst afterglows.  With the recent great improvement in computational power and image differencing algorithms, it is now possible to do this in “real time“. This means that we have identifications of moving and varying objects within an hour of when the observation was taken, allowing prompt followup with Keck, Gemini, and other large spectroscopic telescopes.

For more complete information about the Deep Lens Survey,  as well as for the data you can visit the official survey website at Bell Laboratories.

The Deep Lens Survey


The Deep Lens Survey is a large observing project being run by a large collaboration of researchers  at fifteen different institutions, led by researchers at Brown and Bell Laboratories.  The survey aims to obtain deep multi-color photometry of  seven separate 2-degree by 2-degree patches of sky. 


This is being accomplished using the MOSAIC I and II cameras on the Kitt Peak and Cerro Tololo 4 meter telescopes.  When the survey is completed in 2004, we will have measured positions, magnitudes, and shapes for some 10 million distant galaxies, and we will discover about 200 new clusters of galaxies based solely on their gravitational lensing signal.



       The Group


Prof. Ian Dell’antonio

Room 528


Van Dao

Graduate Student (Rm 717)


Paul Huwe

Graduate Student (Rm 717)


Richard Cook

Graduate Student (Rm 717)


Ryan Michney

Graduate Student (Rm 717)