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B.S., 1991, University of Lund. Ph.D., 1996, University of California Santa Barbara. Fairchild and Senior Postdoctoral Scholar, California Institute of Technology, 1996-2003. Assistant Professor, Cornell University, 2003-2009. Associate Professor, Cornell University, 2009-present.

Research Areas
Experimental Elementary Particle Physics

Current Research

The standard model of particle physics has been extremely successful. It incorporates the strong, electromagnetic, and weak forces. The electromagnetic and weak forces are unified in the standard model. So far the standard model is consistent with all direct observations. One crucial piece of the standard model is still missing; the Higgs particle. The Higgs particle is responsible for generating masses in the standard model. The discovery of the Higgs is one of the primary goals of the LHC (Large Hadron Collider at CERN) which will start operating late 2009.

However successful the standard model has been, it is still believed that it can not be the 'ultimate' theory. At a theoretical level there are 'fine tuning' or 'hierarchy' problems that tells us that new particles have to exist to stabilize the mass of the Higgs. On a different level there are cosmological observations that tell us that the universe is dominated by new forms of energy, dark energy, and matter, dark matter that we have not yet observed! 

Cornell joined the CMS experiment at the LHC in 2005. My main involvement in CMS has been with the 66M channel pixel detector. The CMS pixel detector is placed closest to the proton-proton interaction point. The excellent spatial resolution of the pixel detector is used to reconstruct vertex positions and seed the track finding. Cornell has been the major contributor to the online software and calibration of the pixel detector. We are also involved with the commissioning and operation of the detector. With planned increases in the luminosity of the LHC over the next decade, we will have to upgrade the detectors of CMS. I'm involved with studies and R&D for upgrades to the tracking detectors. Future tracking detectors will need to provide information to the trigger, which means that some level of data reduction, e.g. by selecting high momentum tracks, is needed on the detector. We are studying different ideas for building modules with two closely spaced sensors that can provide a local correlation to allow rejection of low momentum tracks. With graduate student Souvik Das, I have looked at tau identification in CMS for the W to tau channel.

In addition to my work on CMS, I'm a member of the CLEO collaboration. My work here has focused on the study of hadronic D and Ds decays. Precise measurements of these decays allow us to better constrain parameters of the standard model. I'm also interested in simulations of particle decays, and improving the performance of the detector by developing better techniques for calibration. 
 
Graduate Students
Souvik Das and Benjamin Kreis