Twist-2 Generalized TMDs and the Spin/Orbital Structure of the Nucleon

Understand

Generalized transverse-momentum dependent parton distributions (GTMDs) encode the most general parton structure of hadrons.

• Here we focus on two twist-2 GTMDs which are denoted by $F_{1,4}$ and $G_{1,1}$ in parts of the literature.
• As already shown previously, both GTMDs have a close relation to orbital angular momentum of partons inside a hadron.
• However, recently even the mere existence of $F_{1,4}$ and $G_{1,1}$ has been doubted.