I worked with Prof. Gerald Gabrielse and the ATRAP (formerly TRAP) collaboration at CERN and Harvard on the production of cold antihydrogen from trapped positrons and antiprotons. The plot to the right shows the resonance splitting of a cloud of about 1,000,000 positrons interacting with a high-Q RF resonator. We capture the positrons in a Penning trap held at liquid helium temperature (4K).

First ever simultaneous trapping of antihydrogen constituents

In December of 1996, at the CERN Low Energy Antiproton Ring (LEAR), we were able to capture positrons and anitprotons simultaneously in the same apparatus, and to observe their interaction. Unfortunately, the LEAR facility closed permanently immediately after our run, so we are eagerly readying an apparatus for the new Antiproton Decelerator (AD) at CERN. One of our traps for holding antimatter is shown in the photo at right.

Radiation Safety:

Working with antimatter requires some care; here are some links to radiation (and other) safety:

Safety and Health Aspects of X-ray Radiation (a very nice tutorial on radiation measurement and safety!)

Harvard Environmental Health and Safety
 
 

I am also working on precision spectroscopy of Helium in order to measure the fine structure constant accurately by purely atomic means.