Left-right asymmetry of transverse densities from chiral dynamics

29 Apr 2015, 12:00


WG6 Spin Physics WG6 Spin Physics


Carlos Granados (Uppsala University)


The nucleon's peripheral transverse charge and magnetization densities are computed in chiral effective field theory in the light--front formulation. The densities are represented in first--quantized form, as overlap integrals of chiral light--front wave functions describing the transition of the nucleon to soft pion--nucleon intermediate states. The new representation leads to a simple quantum--mechanical picture, according to which the orbital motion of the soft pion causes a left-right asymmetry of the light--front current density in a transversely polarized nucleon. The sizeable effect attests to the essentially relativistic nature of chiral dynamics [momenta $k_\pi = O(M_\pi)$] and could be observed in elastic form factor measurements at low momentum transfer. Further applications of this formulation are presented in connection to peripheral GPDs at low x and to form factors of the energy momentum tensor which potentially contribute to a model independent understanding of the proton spin problem.

Primary author

Carlos Granados (Uppsala University)


Christian Weiss (Jefferson Lab)

Presentation Materials