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)

Guan, Y., et al. “Observation of Transverse Λ/Λ[over ¯] Hyperon Polarization in e^{+}e^{-} Annihilation at Belle.Physical Review Letters, vol. 122, no. 4, Feb. 2019, p. 042001. Epmc, doi:10.1103/physrevlett.122.042001. Full Text

Lu, P. C., et al. “Observation of B+ →p Λ ̄ K+K- and B+ → p ̄ Λk+K+ OBSERVATION of ... P.-C. LU et al.Physical Review D, vol. 99, no. 3, Feb. 2019. Scopus, doi:10.1103/PhysRevD.99.032003. Full Text

Watanuki, S., et al. “Measurements of isospin asymmetry and difference of direct CP asymmetries in inclusive B →xsγ decays.” Physical Review D, vol. 99, no. 3, Feb. 2019. Scopus, doi:10.1103/PhysRevD.99.032012. Full Text

Sumihama, M., et al. “Observation of Ξ(1620)^{0} and Evidence for Ξ(1690)^{0} in Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+} Decays.Physical Review Letters, vol. 122, no. 7, Feb. 2019, p. 072501. Epmc, doi:10.1103/physrevlett.122.072501. Full Text

Yusa, Y., et al. “Measurement of time-dependent CP violation in B0 → KS0 π0π0 decays.” Physical Review D, vol. 99, no. 1, Jan. 2019. Scopus, doi:10.1103/PhysRevD.99.011102. Full Text

Seong, I. S., et al. “Search for a Light CP-odd Higgs Boson and Low-Mass Dark Matter at the Belle Experiment.Physical Review Letters, vol. 122, no. 1, Jan. 2019, p. 011801. Epmc, doi:10.1103/physrevlett.122.011801. Full Text

Adam, J., et al. “Improved measurement of the longitudinal spin transfer to Λ and Λ hyperons in polarized proton-proton collisions at s =200 GeV.” Physical Review D, vol. 98, no. 11, Dec. 2018. Scopus, doi:10.1103/PhysRevD.98.112009. Full Text

Berger, M., et al. “Measurement of the decays Λc → Σππ at Belle.” Physical Review D, vol. 98, no. 11, Dec. 2018. Scopus, doi:10.1103/PhysRevD.98.112006. Full Text

Fulsom, B. G., et al. “Observation of ϒ(2S)→γη_{b}(1S) Decay.Physical Review Letters, vol. 121, no. 23, Dec. 2018, p. 232001. Epmc, doi:10.1103/physrevlett.121.232001. Full Text


Haasdonk, B., et al. “Invariance in kernel methods by haar-integration kernels.” Lecture Notes in Computer Science, vol. 3540, 2005, pp. 841–51.