Sickles is a collaborator on the ATLAS experiment at CERN and studies what happens when particles of light meet inside the Large Hadron Collider. For most of the year, the LHC collides protons, but for about a month each fall, the LHC switches things up and collides heavy atomic nuclei, such as lead ions. The main purpose of these lead collisions is to study a hot and dense subatomic fluid called the quark-gluon plasma, which is harder to create in collisions of protons. But these ion runs also enable scientists to turn the LHC into a new type of machine: a photon-photon collider.
High Energy Physics
What is High Energy Physics?
In high energy physics we seek to understand the nature of space and time, the characteristics of the forces governing the interactions of matter and energy, and the origins of the properties of the elementary particles. Modern theories of particle physics purport to explain the origin of mass, and hope to unify the descriptions of all the forces, including gravity. With the discovery that "normal" matter constitutes only 4% of the total energy in the universe, the study of dark matter and dark energy has attracted great interest.
What are we doing in High Energy Physics at Illinois?
Our group at the University of Illinois at Urbana-Champaign is active on many fronts.
Our theoretical research program includes a broad particle phenomenology component, including efforts to develop new theories of dark matter and their possible signatures, model physics beyond the standard model with a focus on LHC phenomenology and to develop early-universe theories and study their connections to particle physics. Our lattice QCD effort aims to calculate the hadronic corrections needed for decoding measurements at collider experiments.
The theoretical effort also includes research into fundamental aspects of quantum field theory, string theory, AdS/CFT and quantum gravity. The AdS/CFT duality relates questions in quantum gravity to those in strongly interacting quantum many-body physics, so this effort includes strong interdisciplinary links to condensed matter theory and quantum information theory.
In the experimental program our running experiments are CDF-II and CLEO-c, with ATLAS at the Large Hadron Collider turning on soon. Our astrophysics wing is working on the Dark Energy Survey and in the longer term on LSST. For the even more distant future we are involved in Linear Collider R&D.
Our CDF group is active in top physics, gauge boson physics, flavor physics with bottom hadrons, and the search for the Higgs Boson. We still have a chance to find the Higgs at the Tevatron if it is in the right mass range. But if we don't find it there, ATLAS is just around the corner!
CLEO-c measures many charmed particle properties more than an order of magnitude better than any competitors, providing not only fundamental tests of theory (e.g., leptonic decay rates), but also measurements needed for the precise interpretation of B-factory data.
Focus continues to produce results, including the first observation of interference in D + semileptonic decay.
The Dark Energy Survey (DES) will study dark matter and dark energy through their effect on the acceleration of the universe and on the history of structure formation. We are building a red sensitive and very fast 520 Megapixel camera at the Blanco 4-meter telescope in the Chilean Andes.
The Large Synoptic Survey Telescope (LSST) will provide digital imaging of faint astronomical objects across half of the sky every three days, opening a movie-like window on objects that change or move on rapid timescales: exploding supernovae, potentially hazardous near-Earth asteroids, and distant Kuiper Belt Objects. The superb images from the LSST will also be used to measure the distortions in remote galaxy shapes produced by lumps of dark matter, providing multiple tests of the mysterious dark energy.
Visit the group's website at http://hep.physics.illinois.edu.