ATLAS is one of two main particle detectors under construction that will perform experiments at the Large Hadron Collider (LHC). The LHC is a 16.8 mile (27 km) diameter accelerator ring located 328 feet (~100 m) underground at CERN, the European Organization for Nuclear Research, in Geneva, Switzerland. It is scheduled to turn on and be ready for data-taking by 2008. By colliding particle beams into each other within the detector, physicists can observe the intrinsic behavior of subatomic particles to help understand more about the Standard Model and to unlock valuable information about the origin and nature of our universe. The Santa Cruz Institute for Particle Physics is one of several organizations involved in the development, construction and exploitation of the ATLAS detector.

The Santa Cruz Institute for Particle Physics at the University of California Santa Cruz was a member of the initial group of US institutions that petitioned the DoE and NSF to support US participation in LHC experiments due to the great potential for exciting research. We joined the ATLAS experiment in 1994. Our work has focused on the inner tracker and, by joining at an early stage in its development, we were able to contribute to its specification, design and construction.

Our physicists, staff and students have worked on development of the radiation hard silicon sensors and the radiation hard readout electronics, two areas that we have specialized in for the past 20 years. During the construction phase, we were responsible for testing the custom designed readout integrated circuits (ICs) and assembling and then testing the multi-IC hybrid circuits that became part of each detector module (4088 in total for the detector).

The group's principal physics interest is in searches for physics beyond the standard model, especially from theories with supersymmetry. We are currently studying W/Z + jets events with electrons in the final state as a means of calibrating detector performance and developing data analysis techniques. Many signatures of supersymmetry are similar to these standard model events. Group members also work on improving measurements of jet energies and evaluating inner detector tracking performance.

Our ATLAS group now consists of six senior physicists (faculty and researchers), two postdoctoral researchers and four graduate students. We expect to add more graduate students in the next few years as the LHC becomes operational.