Anselm G. Vossen

Anselm G. Vossen

Assistant Professor of Physics

Office Location: 
Physics Building Room 1885, Box 90305, Durham, NC 27007
Front Office Address: 
Physics Building Room 188, PO Box 90305, Durham, NC 27708
Office Hours: 
by appointment


In Quantum Chromodynamics (QCD), the theory of the strong interactions, the nucleon emerges as a strongly interacting, relativistic bound state of almost massless quarks and gluons.
Fifty years of experimental investigations into the nucleon's internal structure have provided remarkable insight into quark and gluon dynamics. However, many outstanding questions remain.
For example, the origin of the spin of the proton is still eludes us and many other properties of the nucleon cannot yet be derived from first order calculations. Even fundamental aspects like a quantitative understanding of the  origin of the mass of the nuclei (and thus most of the visible mass in the universe) as well as the confinement of quarks into hadrons remain outside our current understanding.

My research approaches these questions from two sides. At the newly upgraded Jefferson Lab facility, we use electron proton scattering data to map out the 3D dynamics of the nucleon. We are in particular interested in polarized probes that are sensitive to spin-orbit coupling in the proton wavefunction.
And at the newly constructed Belle II experiment, we use electron-positron annihilation data, to study how hadrons emergy from initial quarks. We are in particular interested how the quantum numbers of the inital quark, like spin, are expressed in the final state hadrons.

My group also works on precision tests of the flavor sector of the standard model at the intensity frontier. To this end we study the properties of B meson detected with the Belle II experiment.

Education & Training

  • D.R., Albert Ludwigs University of Freiburg (Germany) 2008

  • M.S., Albert Ludwigs University of Freiburg (Germany) 2004

Fellowships, Supported Research, & Other Grants

Research in High Energy Physics at Duke University awarded by US Department of Energy (2019 to 2020)

Jia, S., et al. “Search for ϒ(1S,2S)→Zc+Zc(′)− and e+e−→Zc+Zc(′)− at s=10.52 , 10.58, and 10.867 GeV.” Physical Review D, vol. 97, no. 11, June 2018. Scopus, doi:10.1103/PhysRevD.97.112004. Full Text

Adamczyk, L., et al. “Measurement of the H Λ3 lifetime in Au+Au collisions at the BNL Relativistic Heavy Ion Collider.” Physical Review C, vol. 97, no. 5, May 2018. Scopus, doi:10.1103/PhysRevC.97.054909. Full Text

Adamczyk, L., et al. “Transverse spin-dependent azimuthal correlations of charged pion pairs measured in p↑ + p collisions at s=500 GeV.” Physics Letters, Section B: Nuclear, Elementary Particle and High Energy Physics, vol. 780, May 2018, pp. 332–39. Scopus, doi:10.1016/j.physletb.2018.02.069. Full Text

Nakano, H., et al. “Measurement of time-dependent CP asymmetries in B0 → KS0 ηγ decays.” Physical Review D, vol. 97, no. 9, May 2018. Scopus, doi:10.1103/PhysRevD.97.092003. Full Text

Grygier, J., et al. “Erratum: Search for B →hν ν decays with semileptonic tagging at Belle (Physical Review D (2017) (R) 96 (091101) DOI: 10.1103/PhysRevD.96.091101).” Physical Review D, vol. 97, no. 9, May 2018. Scopus, doi:10.1103/PhysRevD.97.099902. Full Text

Niiyama, M., et al. “Production cross sections of hyperons and charmed baryons from e+e- annihilation near s =10.52 GeV.” Physical Review D, vol. 97, no. 7, Apr. 2018. Scopus, doi:10.1103/PhysRevD.97.072005. Full Text

Masuda, M., et al. “Study of KS0 pair production in single-tag two-photon collisions.” Physical Review D, vol. 97, no. 5, Mar. 2018. Scopus, doi:10.1103/PhysRevD.97.052003. Full Text

Li, Y. B., et al. “Observation of Ξ c(2930) 0 and updated measurement of B-→K-Λc+Λ¯c- at Belle: Belle Collaboration.” European Physical Journal C, vol. 78, no. 3, Mar. 2018. Scopus, doi:10.1140/epjc/s10052-018-5720-5. Full Text

Yelton, J., et al. “Measurement of branching fractions of hadronic decays of the Ω c 0 baryon.” Physical Review D, vol. 97, no. 3, Feb. 2018. Scopus, doi:10.1103/PhysRevD.97.032001. Full Text

AdamczyK, L., et al. “Azimuthal transverse single-spin asymmetries of inclusive jets and charged pions within jets from polarized-proton collisions at s = 500 GeV.” Physical Review D, vol. 97, no. 3, Feb. 2018. Scopus, doi:10.1103/PhysRevD.97.032004. Full Text