Heads of Laboratories
Laboratory of Experimental High Energy Physics
Aimingto understand the creationandevolution of the universe, Goulianosand his colleagues study the basic constituents of matterby analyzing data from collisions of sub-atomic particles accelerated to very high energies. Their research is conducted at the Fermi National Laboratory in Illinois and at CERN in Geneva, Switzerland, using the Large Hadron Collider,the world’s largest sub-atomic particle accelerator.
A large fraction of the energy in particle collisions is converted into a variety of new particles flying away from the collision like 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 all known particles have revealed an inner orderthathas been coded into a theoretical framework known as the Standard Model. Matter in all its forms, from stars to living organisms, is described in terms of twelve fundamental particles, six quarks and six leptons, interacting by exchanging force particles—gluons, photons, or W and Z bosons—following strict mathematical rules based on symmetry principles.
The Goulianos laboratory has made substantial contributions to establishing the Standard Model as the premier theory of particle physics. Their experiments at the Intersecting Storage Rings at the European Organization for Nuclear Research (CERN) provided early evidence for the existence of quarks.In other experiments conducted at the Brookhaven National Laboratory, they discovered and measured the rate of neutrino-proton elastic scattering, confirming the neutral-current interactions predicted by the Standard Model. In the collider detector at Fermilab (CDF) experiment, which used proton-antiprotoncollisionsfrom the Tevatron machine, the Goulianos laboratory contributed to the discovery of the top quark.
The Goulianos team currently participates in the international collaboration of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider at CERN. The main goal of this experimentwas to search for the Higgs particle, which could explain the diversity of quark masses. On July 4, 2012, CMS and ATLAS, another CERN experiment, announced the discovery of a new particle with amass of around 125 billion electron volts andproperties consistent with those expected for the Higgs. Further studies have now positively identified this particle as a Higgs boson, a result corroborated by a CDF measurement. The Higgs discovery marks the end of a half-century’shunt for its existence by thousands of scientists around the worldand intensifies the effort to conduct higher precision experimental teststo look for violations that might come from new physics.
Other physics activities of the Goulianos team at CDF and CMS include working on phenomenologicalmodelsaimed at accommodating gravity in the Standard Model and explaining dark matter and dark energy. In addition, the team is studying diffractive phenomena, which provide a window to a component of the Standard Model important for understanding the structure of particles like the proton.
Carrying over the experience gained at the Tevatron to theirresearch at the Large Hadron Collider, Goulianosand his team are uniquely positioned to further characterize the Higgs boson and make new discoveries in areas of physics beyond the Standard Modelto advance “Scientia Pro Bono Humani Generis.”
Undergraduate degree in chemistry, 1958
University of Thessaloniki
M.A. in physics, 1960
Ph.D. in physics, 1963
Columbia University, 1963–1964
Assistant Professor, 1967–1971
Associate Professor, 1971–1981
The Rockefeller University
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