The angular momentum decomposition in the scalar diquark model.

Apr 10, 2019, 5:23 PM
Rettorato - Aula Principi d'Acaja

Rettorato - Aula Principi d'Acaja

via Verdi, 8 Turin
Parallel Session Talk WG6: Spin and 3D structure WG6: Spin and 3D structure


Mr Arturo Amor (Centre de Physique Théorique, École polytechnique)


One of the challenges of hadronic physics is to fully understand the structure of the proton. In particular, there is nowadays a great interest in the decomposition of its total angular momentum into orbital angular momentum (OAM) and intrinsic
spin, as well as identifying contributions from valence quarks, sea quarks and gluons.

The most common decompositions of OAM are the Jaffe-Manohar (canonical) and Ji (kinetic) decompositions, which differ in the way contributions are attributed to quarks and gluons.
Using perturbation theory, explicit one-loop calculations found that the difference between such decompositions vanishes. We show within the diquark model in QED that the difference appears at two-loop level, supporting the interpretation of such a difference as originating from the torque exerted by the spectator system on the struck quark.

Primary author

Mr Arturo Amor (Centre de Physique Théorique, École polytechnique)


Cédric Lorcé (Ecole polytechnique) Matthias Burkardt (New Mexico State University)

Presentation materials