Left-right asymmetry of transverse densities from chiral dynamics

29 Apr 2015, 12:00
20m
BALLROOM EAST

BALLROOM EAST

WG6 Spin Physics WG6 Spin Physics

Speaker

Carlos Granados (Uppsala University)

Description

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)

Co-author

Christian Weiss (Jefferson Lab)

Presentation materials