Current Work:
 



Research Contributions

  Top Quark, Electroweak, and Exotics Physics

 In 2001-2002, I was co-convener of the top and electroweak group, which was
 one of the four physics group of the CDF collaboration (now the top and electroweak
 groups have been split).  Our group presented its first Run II results at the 2002
 International Conference on High Energy Physics.
 

            The paper is available here             The motivation for this measurement is to test predictions of electroweak
            theory on the interaction of three bosons (triple gauge couplings). In this
            measurement, we want to find out how a photon or a Z boson interact with
            two W bosons.  LEP2 experiments collected thousands of WW pairs and
            set stringent limits on anomalous couplings. The Tevatron is able to probe
            these interactions at higher energies and will provide complementary
            information on anomalous couplings. Paper soon available...
           I have worked on a search for single top production using our Run 1 data sample
         in  collaboration with Sarah Wolinski from the University of Michigan.
         The measurement of the production cross section of single top quarks constitutes
         the most effective way of directly  measuring the $V_{tb}$ element of the CKM matrix.
         This analysis sets the world's best limit on single top production.  I am now working
         with Bernd Stelzer on a Run II measurment of the cross section. Paper available soon...
            I have worked on a search for W' bosons decaying to top and bottom quarks
          with Hyunsoo Kim and Pekka Sinervo.  This channel is especially interesting in
          the case where the right-handed neutrino is heavy enough to close the W' -> lnu
          channel.   In this case, the W'decays to quarks and therefore, the current limits
          that have been obtained using the leptonic decay channels, which assume a very
          light right-handed neutrino, are not applicable.  The results of this analysis are
          presented in a  Physics Review Letters paper. For the case where the right-handed
          neutrino is heavier than the $W^{'}$, we set what is currently the best direct limit on
          the W' mass.

          More recently, I started a search for events containing very high energy jets and
          missing momentum.  These events could provide indirect evidence of weakly
          interacting massive particles (Dark Matter candidates) or evidence of Large
          Extra dimensions.

Offline Software Development and Coordination
 

            We are currently using the high energy physics beowulf cluster at the
            University of Toronto to produce most of CDF's official Monte Carlo datasets.
            Our cluster has ~450 cpus running at 2.4 GHz with about 20 Terabytes of
            disk storage.  The Monte Carlo productions are also done using the University
            of Alberta's Thor cluster.   We are in the process of installing GRID tools
            on the Toronto machine with the goal of also making the cluster a reconstruction
            farm for CDF.           In July 2002, I was appointed as one of the two offline analysis cooridinators
          of CDF.  The offline coordinators are responsible for all software development
          in CDF and help determine the schedule for data processing.          For almost 3 years, I was convener of CDF's calorimetry reconstruction group.
         The group's activities included the development of electromagnetic and jet
         reconstruction, missing transverse energy reconstruction, and clustering
         algorithms for our preshower and shower maximum detectors.

        The Run II physics programme places stringent requirements on the
        simulation of our calorimetry systems. I replaced the Run I parameterization
        software by a package initially developed by the H1 collaboration (Gflash).