1981-82 CDF -- The CDF (Collider Detector at Fermilab) experiment is a proton-antiproton collider experiment that studied weak W and Z bosons in the 1980's and is famous for the top quark discovery in the 1990's. It's best-known current research is the search for the Higgs boson. My contribution as a graduate student was in design studies for the muon system before the detector was built.

1982-86 MarkIII -- The MarkIII experiment at SLAC was an electron-positron collider for charm physics at the Psi charmonium resonances. My graduate thesis on this experiment was a measurement of D meson branching fractions.

1986-90 UA2 -- The UA2 (Underground Area 2) experiment at CERN was famous as the co-discoverer (with, you guessed it, UA1) of the W and Z bosons in 1983. I joined the collaboration as a CERN scientific associate and later took a CERN staff appointment to contribute to the first precision measurements of W and Z characteristics.

1990-00 SLD -- The SLD experiment at SLAC was the first high energy electron-positron linear collider. It used the Stanford 2-mile linear accelerator to produce Z bosons for high precision studies. My work on this experiment involved development of an energy spectrometer for beam energy measurements and B meson studies. My graduate student, Cheng-Ju Stephen Lin, wrote his Ph.D. thesis on a search for Bs mixing.

1991-98 E791 -- The E791 experiment at Fermilab was a fixed target charm hadroproduction experiment for studying weakly decaying charmed mesons and baryons. One of its claims to fame was the largest dataset of its time, about equal to the information content of the Library of Congress, which was stored on video cassette tape. My work on this experiment was in reconstruction software and a search for D meson mixing.

1997-2004 BaBar -- BaBar at SLAC is one of two B factories currently operating, making high statistics measurements of B mesons, especially CP violation measurements. My work on this experiment has involved supervising undergraduate projects on calorimeter reconstruction software, neural net data selection techniques, and Ds meson branching fractions.

2003-present VERITAS -- The VERITAS collaboration is an outgrowth of the very successful Whipple collaboration, which has been known for studies of very high energy gamma ray showers since the 1980's. The proposed VERITAS project is a four-telescope array, which is due to start data taking in October 2004 with the first telescope. The completed array is expected to be installed on the top of Kitt Peak by 2006. My work on this experiment has been in software development for database and repository systems, and in neural net algorithms for gamma ray selection. Ongoing interests include a search for dark matter annihilation to gamma rays, and Lorentz violating speed of light measurements.

The VERITAS gamma ray experiment is currently my primary research interest.

Very High Energy Gamma Ray physics combines many of the scientific interests of astrophysics and particle physics. For the particle physicist, the cosmos contains the highest energy accelerators available, and may ultimately prove to be the final frontier in fundamental physics.

To date, very high-energy gamma rays have been observed from a variety of sources (active galactic nuclei, pulsar-powered nebulae, supernova remnants and an X-ray binary system), offering a wealth of scientific information. Because gamma rays are not as strongly attenuated in the galaxy as longer wavelength radiation, they offer a clear and unique view through the galactic plane. In addition, because of their interaction in infrared photon fields and in strong magnetic fields via   pair production, they can be used to probe intergalactic radiation fields. Finally, the highest energy gamma rays, which are beyond any energies that can be produced on Earth, provide a unique probe of many fundamental particle theories.

Much of the science of VHE gamma rays can be grouped into one of two categories. The first concentrates on understanding the mechanism of gamma ray production in cosmic sources and looking for new sources of gamma rays. The second focuses on fundamental particle physics issues that can be probed by nature's cosmic accelerators. Two studies in the latter category have especially captured my interest at UMass: measurement of gamma ray speeds (relevant to theories of Quantum Gravity) and search for neutralino annhilation into gamma rays (an important search for dark matter).

More details of UMass involvement in VERITAS can be found here.