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Grad student rotations available!

Over the last 15 years our group has been central to many developments in the field of neutrino physics. Click here for more of our group history

We are presently operating the EXO-200 double-beta decay experiment at the WIPP underground site in southern New Mexico. This is one of the largest and more sophisticated experiments presently searching for neutrinoless double beta decay. The discovery of such a decay would establish the existence of 2-component Majorana Fermions (mundane Fermions, like the electron, are 4-component Dirac particles), demonstrate the violation of the lepton number and, possibly, establish the neutrino mass scale. A short article in Physics World explains the search for neutrinoless double beta decay.

Within the broader EXO program we are developing new methods to extend the sensitivity of a future multi-ton experiment,nEXO. This work has two major divisions, the first involves the extraction and identification (tagging) of the Ba atom produced in the double-beta decay of Xe using AMO techniques. The second is developing and testing new components and technologies for the nEXO detector to improve the charge and light readout; this includes work with silicon photomultipliers and modular pads for charge readout.
A new setup has just been built to characterize the performance of such devices in Liquid Xenon.

We have started a new program to investigate the nature of gravity at length scales near 1 micron. This work uses ~5 micron diameter silica spheres, which are optically trapped and manipulated in vacuum using lasers. Monitoring the motion of these spheres as they are positioned near gravitational attractors allows us to search for new forces that may appear at micron distances.

We also have a program to develop novel radiation detectors for application to science, homeland security and medical physics.

We have openings for new graduate students in (almost) all of the projects above.

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