Professor Qian focuses his research on the DØ experiment at the Fermilab Tevatron proton-antiproton collider, currently the highest energy collider in the world. At the Tevatron collider, protons and antiprotons are accelerated to ~ 1 TeV and are brought to collide in two massive detectors constructed to detect and record fragments and traces of the collisions. DØ is an international collaboration of approximately 600 scientists and students from 18 nations who have pooled their resources to build and operate one of the two detectors. The data recorded enable DØ physicists to study interactions between fundamental particles and to search for new phenomena to understand nature at its deepest level.

The Michigan DØ group led by Professor Qian has been making significant contributions to the DØ physics program, detector upgrade, and computing and software projects. The group played a significant role in the discovery and its subsequent measurement of the top quark based on the data recorded between 1992 and 1996. The discovery completed the roster of matter particles of a very successful particle theory called Standard Model.

Both the Tevatron collider and the DØ detector have undergone extensive upgrades since the last data-taking period. The Michigan group led the development of the central preshower detector designed to improve electron/photon identification and electromagnetic energy resolution. The current data-taking is expected to increase the previous dataset by at least a factor of 20 and therefore offer greater physics possibilities. Professor Qian is currently the physics coordinator, responsible for the physics effort of the experiment.

Search for Large Extra Dimensions in the Monojet + MET Channel with the Dzero Detector, (DØ Collaboration), Phys. Rev. Lett. 90, 251802 (2003).

Experimental Search for Chargino and Neutralino Production in Supersymmetric Models with a Light Gravitino, (DØ Collaboration), Phys. Rev. Lett. 80, 442 (1998).

A New Detector Technique Using Triangular Scintillating Strips to Achieve Precision Position Measurements for Minimum Ionizing Particles, (M. Adams et al), Nucl. Instrum. And Methods A 378, 131 (1996).

Observation of the Top Quark, (DØ Collaboration), Phys. Rev. Lett. 74, 2632 (1995).

A Determination of the Properties of the Neutral Intermediate Vector Boson Z, (L3 Collaboration), Phys. Lett. B 231, 509 (1989).