EDUCATION
B.S., University of Madras (1969)
M.S., University of Madras (1971)
Ph.D., Columbia University (1976)

FOCUS 

Elementary particles are the smallest constituents of matter that can be studied with the most powerful microscopes (colliding beams of ultra-high-energy protons, electrons, and their antiparticles) that are available today. I am interested in gauge theories of elementary particles and their interactions, especially the SU(2)xU(1) theory of electroweak interactions and the quantumchromodynamic theory of strong interactions. I work on predicting cross sections for high-energy collision reactions currently being studied by experimenters at the Fermi National Accelerator Laboratory (Fermilab) Tevatron Collider and at the CERN Electron-Positron Collider LEP, and planned for study at future high-energy physics facilities, such as the LHC Collider at CERN.

I am also interested in computational physics. I develop computer algebra algorithms and programs for performing Feynman diagram calculations in high-energy physics, I use Monte Carlo methods to simulate field theoretical and statistical systems, and I am also interested in computer-based methods in physics instruction.

SELECTED PROJECTS

• One-loop radiative corrections to photon-photon scattering cross sections
• Parity-violating asymmetries in the minimal supersymmetric extension of the standard model
• Resummation of large logarithmic contributions in electroweak boson production at small transverse momentum
• Software in C++ for performing Feynman diagram calculations in supersymmetric quantum field theories
• Monte Carlo simulations of melting of the Abrikosov vortex lattice

PUBLICATIONS

• R. J. Gonsalves and C.-F. Wai. Chromo-electroweak interference and parity-violating asymmetries in electroweak boson pair production. Phys. Rev. D 49:190­218 (1994); Erratum: ibid., 51:1428 (1995).
• R. J. Gonsalves, C. M. Hung, and J. Pawlowski. Heavy-quark triangle diagram contributions to Z boson production in hadron collisions. Phys. Rev. D 46:4930­42 (1992).
• R. J. Gonsalves, J. Pawlowski, and C.-F. Wai. Scale dependence of the W and Z distributions at large transverse momentum Phys. Lett. B 252:663­68 (1990).
• R. J. Gonsalves. Theory of the W/Z transverse momentum distribution. In Proceedings of the Rice Meeting, 1990 Meeting of the Division of Particles and Fields of the American Physical Society, Houston, Texas, January 3­6, 1990, B. Bonner and H. Miettinen eds. (World Scientific, Singapore, 1990) pp. 536­40.
• R. J. Gonsalves, J. Pawlowski, and C.-F. Wai. QCD radiative corrections to electroweak-boson production at large transverse momentum in hadron collisions. Phys. Rev. D 40:2245­68 (1989).

A sample calculation of high-energy cross-sections in the standard model.

Fig 1 Set of Feynman diagrams, involving quarks, leptons, and gauge bosons, that must be computed.

Fig 2 Predictions for parity-violating cross-sections in hadron-hadron collisions as a function of the center-of-mass energy s of the colliding hadrons.