Aida X El-Khadra



Aida X El-Khadra

Primary Research Area

  • High Energy Physics
429 Loomis Laboratory


Professor Aida El-Khadra received her PhD. in 1989 from the University of California, Los Angeles, after receiving her diplom from Freie Universitaet, Berlin, Germany. She held postdoctoral research appointments at Brookhaven National Laboratory, Fermi National Accelerator Laboratory, and the Ohio State Univerity before joining the Illinois faculty in 1995. El-Khadra is a fellow of the American Physical Society, a recipient of the Department of Energy's Outstanding Junior Investigator Award, and a Sloan foundation fellow. In addition to a number of other research and teaching awards she was also recently named a Fermilab Distinguished Scholar. El-Khadra is currently serving on the APS Division of Particles and Fields (DPF) executive committee.

Prof. El-Khadra's area of research is theoretical particle physics. Her research focuses on the application of lattice Quantum Chromodynamics (also called the strong interactions) to phenomenologically interesting processes in flavor physics, which are relevant to the experimental effort at the so-called intensity frontier. She is a leader of one of the most successful collaborations working in Lattice Field Theory in the world, the Fermilab Lattice collaboration. Select highlights include the first quantitative determination of the the strong coupling from lattice QCD, a new formulation of heavy quarks on the lattice that is the foundation of many important, phenomenologically relevant lattice calculations, for example, predictions of the D and Ds meson decay constants, predictions of the shape of the semileptonic D-meson form factors, and lattice calculations of semileptonic B-meson form factors that yield the most precise determinations of the associated CKM matrix elements, Vcb and Vub to date. Other recent highlights are the most precise calculations of (a) the semileptonic Kaon form factor which improves upon our knowledge of the CKM matrix element Vus, (b) the complete set of semileptonic form factors for B-meson decays to pions, and kaons, yielding new interesting constraints on models of new physics, and (c) the complete set of the neutral B and Bs meson mixing matrix elements, yielding the best-to-date constraints on Vtd, Vts, and their ratio.

Research Statement

Phenomenology with Lattice QCD
Quantum chromodynamics (QCD), the theory of the strong interactions, is amenable to perturbative calculations only at high energies. A quantitative understanding of the low-energy behavior of QCD, like the interactions of quarks inside hadrons, requires nonperturbative methods. Lattice field theory offers a systematic approach to solving QCD nonperturbatively. The space-time continuum is replaced by a discrete lattice. Part of our research is concerned with improvements in the formulation of lattice QCD. Other projects deal with applications of lattice QCD to phenomenologically interesting processes that test the standard model of particle physics and potentially yield insight into new physics scenarios.

Teaching Honors

  • Collins Award for Innovative Teaching, COE (2002)
  • Distinguished Scholar, Fermilab (2016)
  • Fellow, American Physical Society (2011)
  • Center for Advanced Study Associate (2007)
  • Frontier Fellow, Fermilab (2002)
  • Beckman Fellow in the Center for Advanced Study (1998)
  • Xerox for Faculty Research Award (1998)
  • A. P. Sloan Foundation Fellow (1997)
  • DOE Outstanding Junior Investigator Award (1996)

Selected Articles in Journals

Articles in Conference Proceedings

Related news

  • Accolades
  • High Energy Physics

Aida El-Khadra, a professor of physics specializing in high-energy theory at the University of Illinois at Urbana-Champaign, is one of four scientists nationwide recently appointed Fermilab Distinguished Scholars.

Fermilab Distinguished Scholars are rotating multi-year appointments for U.S. particle theorists in the Fermilab Theoretical Physics Department. The Fermilab Director appoints Scholars for a term of two years, with the possibility of a one-year extension by mutual agreement. Fermilab Distinguished Scholars are expected to spend at least one month total per year in residence at Fermilab. During the term of their appointment, Scholars have a Fermilab affiliation and the same research opportunities and support infrastructure as Fermilab scientists. Scholars are encouraged to propose and/or participate in thematic programs organized with members of Fermilab's Theoretical Physics and Astrophysics Departments.

  • Research
  • High Energy Physics

A team of theoretical high-energy physicists in the Fermilab Lattice and MILC Collaborations has published a new high-precision calculation that could significantly advance the indirect search for physics beyond the Standard Model (SM). The calculation applies to a particularly rare decay of the B meson (a subatomic particle), which is sometimes also called a “penguin decay” process.