Heads of Laboratories
In an attempt to understand the creation, evolution and eventual fate of the universe, Dr. Goulianos and his colleagues study the basic constituents of matter and their interactions, watching as particles are accelerated to very high energies and brought into head-on collisions. Their research is concentrated at the Fermilab Tevatron Collider in Illinois and at the Large Hadron Collider in Switzerland.
A large fraction of the energy in particle collisions is converted into particles flying away from the collision point in a fashion reminiscent of exploding fireworks. Most of the created particles have an ephemeral existence, decaying after a brief period of time into more stable ones. Detailed studies of the properties of all known particles have revealed an inner order, which has been coded into a theoretical framework known as the Standard Model. Matter in all its forms, from stars to living organisms, can be described in terms of 12 fundamental particles, six quarks and six leptons, interacting among themselves by exchanging force particles — gluons, photons or W and Z bosons — following strict mathematical rules based on symmetry principles.
Founded in 1970, Dr. Goulianos’s laboratory has made substantial contributions to establishing the Standard Model as the premier theory of particle physics. Experiments of lab members at the Intersecting Storage Rings at CERN, the European Organization for Nuclear Research, were among the first to provide evidence for the existence of quarks through the measurement of high transverse momentum particle production. In other experiments at the Brookhaven National Laboratory, the team discovered and measured the rate of neutrino-proton elastic scattering, confirming the neutral-current interactions predicted by and essential to the foundation of the Standard Model; and using the Fermilab Tevatron, the Goulianos laboratory contributed to the discovery of the top quark. Despite its phenomenal predictive power, the Standard Model is far from the “theory of everything.” It does not incorporate gravity and has no obvious explanation for dark matter or dark energy, of which most of the universe is made. The ultimate theory, the “DNA of nature,” is still at large.
Using data collected by the Collider Detector at Fermilab (CDF) at the proton-antiproton Tevatron collider, Dr. Goulianos and his colleagues have been performing searches for the Higgs particle (the quantum of the field that could explain the diversity of quark masses) and for supersymmetry and extra dimensions (theoretical ideas aimed at accommodating gravity and explaining dark matter and dark energy), and studying difractive phenomena. The latter provide a window to non-perturbative quantum chromo-dynamics, a component of the Standard Model important for understanding the structure of strongly interacting particles like the proton. The data for these searches have been collected with the CDF II detector, in which the Goulianos laboratory has made seminal contributions to several crucial detector components, including the plug calorimeter, the shower-maximum detector and the scintillator-tile pre-shower detector. Tevatron collider operations ceased in September 2011, but data analysis is still continuing. About 30 papers are in preparation, including one on evidence for a Higgs-like enhancement in the mass range around 115-135 GeV.
The Goulianos laboratory also participates in the international collaboration of the Compact Muon Solenoid (CMS) experiment at CERN's Large Hadron Collider (LHC), the world’s largest particle accelerator. The accelerator is currently operating at energies 3.5 times higher than the Tevatron, which increases the discovery potential for new physics within and beyond the Standard Model. Team members have been working on measuring the energies of jets (the streams of particles that are emitted when quarks or gluons interact) and developing statistical techniques. Measuring the directions and energies of the particles in a jet allows scientists to, for instance, differentiate the Higgs’s mass from its decay products, while statistical techniques help optimize the data analysis. On July 4, 2012, in a joint seminar with the ATLAS experiment at the LHC, the CMS and ATLAS experiments announced the discovery of a new particle of mass around 125 GeV with properties consistent with those expected for the Higgs. Although many new particles have been discovered over the last 50 years, none is as fundamental, and as crucial to our understanding of the universe, as the Higgs boson.
Dr. Goulianos and his team are continuing their current program at the LHC, aiming at further characterizing the newly discovered Higgs-like particle and looking forward to discoveries in the areas of diffraction and beyond the Standard Model physics.
Dr. Goulianos was born in Thessaloniki, Greece, and studied chemistry at the University of Thessaloniki, where he graduated in 1958. Later that year he came to the United States as a Fulbright Scholar and earned his Ph.D. in physics from Columbia University in 1963. He continued at Columbia as a research associate until 1964, when he joined Princeton University as an instructor and was promoted to assistant professor in 1967. Dr. Goulianos joined Rockefeller as associate professor in 1971 and was named professor in 1981. Dr. Goulianos is a fellow of the American Physical Society.
|Return to full listing|