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)

Adamczyk, L., et al. “Measurement of the cross section and longitudinal double-spin asymmetry for dijet production in polarized pp collisions at s =200 GeV.” Physical Review D, vol. 95, no. 7, Apr. 2017. Scopus, doi:10.1103/PhysRevD.95.071103. Full Text

Wehle, S., et al. “Lepton-Flavor-Dependent Angular Analysis of B→K^{*}ℓ^{+}ℓ^{-}.Physical Review Letters, vol. 118, no. 11, Mar. 2017, p. 111801. Epmc, doi:10.1103/physrevlett.118.111801. Full Text

Adamczyk, L., et al. “Elliptic flow of electrons from heavy-flavor hadron decays in Au + Au collisions at √sNN =200, 62.4, and 39 GeV.” Physical Review C, vol. 95, no. 3, Mar. 2017. Scopus, doi:10.1103/PhysRevC.95.034907. Full Text

Nanut, T., et al. “Observation of D^{0}→ρ^{0}γ and Search for CP Violation in Radiative Charm Decays.Physical Review Letters, vol. 118, no. 5, Feb. 2017, p. 051801. Epmc, doi:10.1103/physrevlett.118.051801. Full Text

Adamczyk, L., et al. “Charge-Dependent Directed Flow in Cu+Au Collisions at sqrt[s_{NN}]=200  GeV.Physical Review Letters, vol. 118, no. 1, Jan. 2017, p. 012301. Epmc, doi:10.1103/physrevlett.118.012301. Full Text

Adamczyk, L., et al. “ϒ production in U + U collisions at sNN =193 GeV measured with the STAR experiment.” Physical Review C, vol. 94, no. 6, Dec. 2016. Scopus, doi:10.1103/PhysRevC.94.064904. Full Text

Adare, A., et al. “Azimuthally anisotropic emission of low-momentum direct photons in Au + Au collisions at sNN =200 GeV.” Physical Review C, vol. 94, no. 6, Dec. 2016. Scopus, doi:10.1103/PhysRevC.94.064901. Full Text

Metz, A., and A. Vossen. “Parton fragmentation functions.” Progress in Particle and Nuclear Physics, vol. 91, Nov. 2016, pp. 136–202. Scopus, doi:10.1016/j.ppnp.2016.08.003. Full Text

Adamczyk, L., et al. “Measurement of elliptic flow of light nuclei at sNN =200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV at the BNL Relativistic Heavy Ion Collider.” Physical Review C, vol. 94, no. 3, Sept. 2016. Scopus, doi:10.1103/PhysRevC.94.034908. Full Text

Adamczyk, L., et al. “Jet-like correlations with direct-photon and neutral-pion triggers at sNN=200 GeV.” Physics Letters, Section B: Nuclear, Elementary Particle and High Energy Physics, vol. 760, Sept. 2016, pp. 689–96. Scopus, doi:10.1016/j.physletb.2016.07.046. Full Text