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Introduction

My area of research is Elementary Particle Physics. The underlying goal of this research is to obtain a full (or at least better) understanding of nature at its most fundamental level. In partcular, what are the smallest constituents of matter and how do these fundamental particles interact with one another. Currently, it is the so-called Standard Model of Particle Physics which describes the  fundamental particles (quarks and leptons) and the way in which they interact via the known forces (Electromagnetic, Weak and Strong forces). While this model is successful in describing much of the currently available data, there is good reason to believe that it cannot be the final answer, as it does not address some very fundamental questions, such as:

1) Why are there 3 nearly identical generations of quarks & leptons (mainly differing by their masses)
2) Why is the universe made almost entirely of matter, with almost no antimatter?
3) Why do particles have the masses that they do?
4) What is the dark matter of the Universe? The standard model does not include any particle candidate for this dark matter.
5) Are quarks and leptons fundamental? That is, might they be made up of smaller structures?
6) Is there really a HIggs boson (or multiple Higgs bosons) which endows particles with their masses? 
7) What's going on with neutrinos? What are their masses and mixings?

I'm currently involved in two experiments: CLEO and LHCb. See the brief descriptions below for for more information on these experiments,

CLEO Experiment
The CLEO Experiment takes place at the Cornell Electron Storage Ring (CESR) at Wilson Laboratory, Cornell University, in Ithaca, N.Y. The CESR collider produces beams of electrons and positrons (positive electrons) which annihilate at the interaction region where the CLEO detector is located. Until about 2003, CLEO operated with beam energies around 5 GeV, which allowed for the production of bound states of resonant bound states of a b quark and an b anti-quark, known as the Upsilon resonances. Resonant states, in order of increasing mass included the Y(1S), Y(2S), Y(3S), Y(4S) and Y(5S), each which were produced and studied by CLEO physicists. Below the Y(4S), the resonance decays to light hadrons, and provides a wealth of information on the nature of the strong force. At and above the Y(4S), which has a mass of about 10.6 GeV, the resonance can decay into a pair of b mesons (either B+/B- or B0-B0bar) each having a mass of about 5.28 GeV. A wealth of information about b-decays has come from CLEO including some of the most precise measurements of branching ratios, form factors, CKM matrix element determinations, and rare decays. One of the most recent and elegant pieces of work was the first observation of penguin loop diagrams which give rise to a direct b to s quark transition. The rates observed are consistent with standard model predictions, providing a very stringent test of the standard model.

       CLEO has now moved into the CLEO-c phase where it has lowered the beam energy to about 2 GeV, allowing for the production of the psi resonances. The psi(3770) decays predominantly to D D-bar, allowing for precision measurements in the charm sector. The goals of this phase of the CLEO program are the precision measurements of decay constants, charm branching fractions and form factors, study of D-mixing, limits or observation of CP Violation in the charm quark system, and rare decays of charm and tau leptons. 

At a slightly lower energy, below the charm threshold, CLEO can perform precise spectroscopic measurements of charm-anticharm resonant states, which have the potential to be a factory for so-called "glueballs". Because of the nature of the strong force, the force carriers, called gluons, can interact with each other and form a bound state. The theory allows for such states to arise, but so far no such particles have been discovered. A discovery of glueballs would provide yet another strong piece of evidence for the theory of strong interactions (known as Quantum Chromodynamics, or QCD).

LHCb Experiment
One of the key elements to the standard model of particle physics is the presence of a 3x3 unitary matrix which relates the mass eigenstates of the Hamiltonian to the flavor eigenstates of the Weak Interaction. In one representation of this Unitary matrix there are 3 angles and one complex phase. The presence of this complex phase allows for the phenomenon known as CP Violation. CP-violation can produce differences in the rates at which particles and anti-particles decay, and therefore is intimately tied to the question of baryogenesis. Because the b-quark sector is expected to exhibit large CP asymmetries in decay rates between b-particles and b-antiparticles, a detailed study of the decay rates of these particles places severe constraints on the standard model. When combined with other similar measurements, the hope is to eventually observe effects which cannot be accommodated by the standard model, and perhaps shed some light on a more complete theory of matter and the universe.

      The LHCb Experiment is being designed to perform these precision measurements of the matter-antimatter asymmetries in the b-quark sector. The experiment will run at the Large Hadron Collider (LHC), which accelerates protons and antiprotons to an energy of 1 TeV and collides them into one another. In about 1/1000 collisions, a pair of b quarks are created, and these are the events in which the BTeV experiment is most interested. The LHCb detector  uses a 3-level trigger, a precision silicon vertex detector, excellent tracking,
and a highly parallelized set of processors to weed out most of the uninteresting events, and accept approximately half of the reconstructable b-quark events. The experiment is expected to be fully constructed and installed by about mid-2007.

A photograph and more information about the LHCb experiment can be found here.

This work is carried out by the Syracuse High Energy group  and is supported by the National Science Foundation.

Global Alignment of the LHCb Detector
         Precise alignment of the entire LHCb detector is critical in order to achieve optimal momentum and spatial resolution. All subdetectors, must be brought into relative alignment with one another. Because the Vertex detector (VELO) moves is extracted and reinserted with each fill of the LHC (in order to avoid large radiation doses) the alignment constants are expected to be checked and possibly updated for each fill of the LHC. This effort requires coordination among all the subdetector groups, and development of algorithms to perform automated alignment between the subdetectors. All alignment constants need to be propagated to the databases which store the constants (the so-called "Conditions database). For more information, please visit my web page on Global Alignment.

Recent Publications 

Graduate Students