An exotic phase of nuclear matter, known as Quark Gluon Plasma, existed a few microseconds after the Big Bang. We recreate this matter in the laboratory by smashing together lead atoms, without their accompanying electrons, at very high energies using a huge particle accelerator (the Large Hadron Collider, or LHC) at the CERN research laboratory in Switzerland. We investigate the properties of this new form of nuclear matter by measuring a specific type of particle produced in the collision. This type of particle, called heavy hadronic resonances, contain much more massive quarks than those making up ordinary protons and neutrons. These heavy resonances are created within the matter or medium, interact with it, and then decay into particles we can detect in the experiment, thus carrying information about the expanding medium. These heavy resonances become test particles to probe the characteristics of this newly created matter, which only exists in the order of a few hundred yoctoseconds (10^-24 seconds).

The Early Career grant enabled me to investigate the production and interactions of heavy resonance particles in this new phase of matter at the LHC, which is the most powerful particle accelerator in the world. With this award, I was able to join the ALICE detector collaboration with my newly formed group to conduct these studies. The ALICE collaboration consists of 1700 scientists from 170 institutions from around the world. My research group is expanding to include new detector developments and new investigations requiring even heavier and rarer probe particles. All these efforts contribute to uncovering the mysterious features of the very high temperature state of nuclear matter called the Quark Gluon Plasma. 

Christina Markert is a professor in the Department of Physics at the University of Texas in Austin.

The Early Career Award program provides financial support that is foundational to young scientists, freeing them to focus on executing their research goals. The development of outstanding scientists early in their careers is of paramount importance to the Department of Energy Office of Science. By investing in the next generation of researchers, the Office of Science champions lifelong careers in discovery science. 

For more information, please go to the Early Career Research Program.

An Experimental Research Program on Chirality at the LHC

One of the main remaining topics in the nuclear evolution of the universe is a profound understanding of the phase transition from partonic (quark‐gluon) to hadronic (nucleon) matter, which happened a few microseconds after the Big Bang. According to modern calculations, two fundamental symmetries of quantum chromodynamics, chirality and color as well as its deconfinement, are expected to be restored at the transition to the quark‐gluon plasma. Experiments at the Relativistic Heavy Ion Collider have yielded evidence of color deconfinement, but it is conceivable that the facility is not energetic enough to populate the high mass resonance states relevant to studies of chirality. This project will develop and apply a new analysis strategy to study chirality using hadronic resonances detectable with the ALICE experiment at the very high energy Large Hadron Collider at CERN.

B. Abelev, et al. (ALICE Collaboration), Phys. Rev. C 91, 024609 (2015). [DOI: 10.1103/PhysRevC.91.024609]

J. Adam, et al. (ALICE Collaboration), Eur. Phys. J. C 76, 245 (2016). [DOI: 10.1140/epjc/s10052-016-4088-7]

A.G. Knospe, C. Markert, K. Werner, J. Steinheimer, and M. Bleicher, “Hadronic resonance production and interaction in partonic and hadronic matter in the EPOS3 model with and without the hadronic afterburner UrQMD.” Phys. Rev. C 93, 014911 (2016). [DOI: 10.1103/PhysRevC.93.014911]

Additional profiles of the 2010 Early Career Award winners can be found at: https://www.energy.gov/science/listings/early-career-program. 

The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit www.energy.gov/science.

Sandra Allen McLean is a Communications Specialist in the Office of Science, [email protected].