## Other Research Projects

## Quantum Gravity

- Perturbative relationships between gravity and gauge theories
- Multi-loop diagrams
- Phenomenology of theories with higher dimensions
- Study of collider signatures of TeV scale quantum gravity with large extra dimensions

## Phenomenology of Supersymmetry and Grand Unified Theories

- R-parity violation, collider signals for supersymmetric top, Higgs, neutrinos
- R-parity violating sneutrino interactions at lepton and hadron colliders
- Reactions in gauge-mediated supersymmetry
- Unified SUSY models explaining b-quark deviations at SLC and LEP
- Dynamical explanations for the masses and mixing angles of quarks and leptons

## Tests of the Standard Model

- Study of WW scattering to t tbar as a probe of the strongly interacting Higgs sector
- Investigation of CP violation in tau lepton decay
- Top-charm associated production in e+e- collisions
- models for baryogenesis; neutrino and Sneutrino mixing and oscillation
- sterile neutrinos

## QCD Phenomena

- Pomeron-odderon interference in diffractive photoproduction of heavy quarks
- Disordered chiral condensate phenomena
- Applications of light-front quantization to phenomenology
- Calculation of four-jet production
- Commensurate scale relations and scheme-invariant predictions
- Inclusion of mass-threshold effects into the running of the QCD coupling and the analytic extension of the MSbar scheme
- Commensurate scale relations -- high precision tests of QCD and the Standard Model without renormalization scale and scheme ambiguity
- Anomalous polarization of quarkonium in hadron collisions
- The role of the color-octet mechanism in hadronic production of quarkonium
- Heavy sea quark structure of hadron wavefunctions and double quarkonium hadroproduction
- Perturbative QCD constraints on the shape of polarized structure functions
- Anomalous angular correlations and higher twist effects in the Drell-Yan process and semi-inclusive pion production
- Studies of diffractive lepto-production of vector mesons in QCD; tests of QCD color transparency and the gluon structure function at low x
- Coherent QCD phenomena: the Landau-Pomeranchuk-Migdal Effect in QED and QCD; quark energy loss in matter
- Effects of multiple scattering and target structure on photon emission
- Leading charm and bottom production and coalescence mechanisms in hadron collisions
- Model-independent relation between the proton magnetic moment and the nucleon axial coupling
- Search for disoriented QCD chiral condensate and studies of intermittency at large pseudo-rapidities
- Theory of hard-diffraction related to observations at HERA
- Gluon radiation in diffractive electroproduction
- The quark/antiquark asymmetry of the nucleon sea
- Scale-fixed predictions for meson form factors and other exclusive reactions
- Probing contact interactions at high-energy lepton colliders
- Rapidity gaps in perturbative QCD
- Novel QCD effects in the production and decay of quarkonium
- The Drell-Yan process in nuclei and factorization in impact parameter space
- Signatures of color octet quarkonium production

## Physics at the International Linear Collider

- Testing Supersymmetry and Extensions of the Standard Model at the NLC exploiting polarized beams
- Production of charginos, leptoquarks, and supersymmetric particles
- Probes of anomalous chromodynamic, weak and flavor-changing couplings at the NLC
- High energy photon-photon collisions at the Next Linear Collider
- Studies of WW scattering at a photon-photon linear collider
- Tests of anomalous moments in the Standard Model in polarized electron-photon collisions
- Studies of the QCD Pomeron in virtual two-photon scattering
- Using final state gluons as probes of anomalous top quark couplings at the NLC
- The polarization asymmetry in photon electron collisions at the NLC and triple gauge boson couplings
- The polarization asymmetry and triple gauge boson couplings in gamma e collisions at the NLC
- Probing flavor changing neutral current top couplings at the NLC
- Tests of the Standard Model and QCD at SLC and LEP
- Higher order effects in measuring electron polarization at the SLC
- New approaches to efficient analytic calculation of higher-order amplitudes in gauge theory, particularly QCD, including processes with large numbers of legs
- Applications to hadron colliders and to three and four-jet decays of polarized Z's at the SLC
- Rapidity Gaps and color coherence in electron-positron collisions
- Renormalization scale effects and tests of QCD in jet production
- Anomalous couplings of quarks and leptons
- Effects of new physics in the decay of the Z to bottom and bottom-strange channels
- Foundations of electroweak symmetry breaking
- Baryogenics and Standard Model CP-violation
- Probing violations of CPT and quantum mechanics in kaon decays and kaon pair production
- Improved high order QED corrections to anomalous leptonic moments
- New method for the production of relativistic anti-hydrogen
- The strong coupling constant in Grand Unified Theories
- Kaon decays beyond the Standard Model
- Probing supersymmetry in rare B decays
- Asymmetric quark/anti-quark hadronization in electron-positron annihilation
- Phenomenological implications of low-energy supersymmetry breaking
- Hadroproduction of quarkonia in fixed target experiments

## Probes of Extended Gauge Sectors at Hadron and Electron-Proton Colliders

- Models of electroweak symmetry breaking by new strong interactions and their implications
- Probes of anomalous top-quark couplings at hadron colliders
- Production of new gauge bosons and leptoquarks at TeVatron, LHC, and future hadron colliders
- Tests of light gluinos
- The electroweak symmetry breaking Higgs boson in models with top quark condensation
- Constraints on anomalous top quark couplings at the LHC
- Searches for scalar and vector leptoquarks at future hadron colliders
- Searches for new gauge bosons at future colliders
- Nuclear effects at HERA

## New Theoretical Methods

- Object-oriented programming applied to simulation problems in physics
- Light-cone Fock state methods in nonperturbative QCD
- Nonperturbative renormalization of QED in light cone quantization
- The relation of BLM and Pade methods for resumming perturbative QCD
- Spontaneous symmetry breaking in supersymmetric Yang-Mills theories
- Superstring theory model-building and phenomenology
- Extension of eikonal methods developed for beamstrahlung studies to the analysis of the suppression of radiation in a medium with multiple scattering, including effects of finite target thickness and of multiple targets
- One-loop amplitudes for multijet production
- Power corrections, renormalons and resummation
- Multiple scattering and functional integrals
- Unitarity based techniques for one loop calculations in QCD
- Precision corrections in the minimal supersymmetric Standard Model