The D0 Experiment is a collaboration of ~600 physicists, including ~100 graduate students, coming from 75 institutions in 19 countries. D0 started taking data in 1992. Run 1 lasted through early 1996, and after a major upgrade the current Run 2 started in 2002. We collect data on proton-antiproton collisions at the Tevatron which is running at a total c.m. energy of 2 TeV. The physics goals of the experiment are discussed briefly below. As for accomplishments, here's a complete list of D0 publications, and here are "plain English" summaries of selected results. The most important result so far is the discovery of the top quark.

The D0 detector is a large, complicated, expensive (~$100M) detector which tries to detect "everything" produced in p-pbar collisions. The intersecting beams are  surrounded by charged particle tracking devices (silicon and fiber) , solenoidal magnet, calorimeters (em and hadron), and a muon system (toroidal magnet and chambers). Collisions happen at a rate of several million per second, and dozens of particles are produced in a typical collision. Only a small fraction of these events selected for further analysis. The interesting objects identified and recorded by the detector are energetic electrons, muons, photons, groups of particles called jets, and "missing Et" (mostly neutrinos). The detector is operated 24/7 by teams of about six physicists.

The broad goal of the D0 experiment is to study the properties and interactions of the Standard Model particles (quarks, leptons, and gauge bosons) and to search for new physics beyond the Standard Model. Topics of current interest include:

• Precise measurement of the top quark mass. The top mass is related to the mass of the (yet-to-be-found) Higgs boson whose interactions with with other particles give rise to mass in the first place. Several top cross-section measurements are also being pursued actively.

• Detailed studies of production and decay properties of particles containing the bottom quark.

• Precise measurements of the W/Z production cross-sections and decay properties.

• Detailed studies of jet production and other tests of QCD (Quantum ChromoDynamics)

• Searches for the Higgs boson in many channels.

• Searches for new phenomena, including supersymmetry, leptoquarks, large extra dimensions, and substructure of quarks and leptons.

More information on each of these topics can be found here.