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Indiana University Bloomington

J. Timothy Londergan

J. Timothy Londergan Emeritus Professor
Nuclear Physics (Theoretical)

B.S., University of Rochester, 1965.
Ph.D., Oxford University, 1969.
Postdoctoral Position: Case Western Reserve University, University of Wisconsin

Phone: Swain West 257 (812)855-5422 | NTC (812)855-2956
Email: tlonderg at

Quark-Nuclear Physics
My research interest is in theoretical nuclear physics. I study the interface between high energy and nuclear physics. In particular, I am interested in the quark/gluon structure of the nucleon (proton or neutron), and in how the nucleus can be used to obtain information regarding the nucleon's structure. I am particularly interested in the status of "broken symmetries" for quarks. These are symmetries that are approximately, but not exactly, satisfied for quark systems. Breaking of these symmetries gives direct evidence for "non-perturbative" quark effects. I also study scattering theory, particularly models of resonance behavior.

Nanotechnology; Quantum Wires
In addition, I am interested in "quantum wires", very narrow 2-dimensional structures in which electrons can move freely. Electrons in quantum wires have exactly the same properties as EM fields in rectangular waveguides. This is part of the new field of "nanotechnology". I have written a monograph on this subject [Binding and Scattering in 2-Dimensional Systems: applications to quantum wires, waveguides and photonic crystals, Londergan, Carini and Murdock, Springer ,1999.]

The Electron-Ion Collider
I am also interested in the possibility of a new facility to study quark-nuclear physics. This machine would collide beams of high-energy electrons (of energy roughly 10-30 GeV) with beams of protons and light ions, or with beams of heavy ions such as gold nuclei. The energies of the protons or heavy ions would be in the range 30-200 GeV. There have been several workshops to investigate what such a machine could accomplish, and the properties of such a facility, now called the "Electron-Ion Collider", or EIC.

Selected Publications

  • Hobbs, Londergan and Melnitchouk, Phenomenology of nonperturbative charm in the nucleon, Phys.Rev. D89, 074008 (2014).
  • Londergan, Nebreda, Pelaez and Szczepaniak, Identification of non-ordinary mesons from dispersive connection between their poles and Regge trajectories: the f0(500) resonance, Phys.Lett. B729, 9 (2014).
  • I. Cloet et al., Charge symmetry breaking in spin-dependent parton distributions and the Bjorken sum rule, Phys.Lett. B714, 97 (2012).
  • Londergan, Peng and Thomas, Charge symmetry at the partonic level, Rev.Mod.Phys. 82, 2009 (2010).
  • Bentz, Cloet, Londergan and Thomas, Reassessment of the NuTeV determination of the weak mixing angle, Phys.Lett. B693, 462 (2010).