10–15 Sept 2012
Puerto del Carmen, Lanzarote
Europe/Lisbon timezone

Where is the proton missing spin?

12 Sept 2012, 09:35
25m
Puerto del Carmen, Lanzarote

Puerto del Carmen, Lanzarote

Canary Islands (Spain)
Talk at plenary session Spin Physics Spin Physics (I)

Speaker

Prof. Bo-Qiang Ma (Peking University)

Summary

It has been over 20 years for the proton spin ``crisis",i.e., the puzzle of where is the proton missing spin. Here I make a review on the explanation that the proton missing spin is due to the relativistic effect of quark transversal motions.
More generally, the transversal motions of quarks play a significant role in various physical quantities related to the proton spin structure, such as the helicity and transversity distributions, and the transverse-momentum-dependent (TMD) or three-dimensional parton distributions (3dPDFs). It is shown that the relativistic effect due to quark transversal motions plays a crucial role to understand the proton spin puzzle.

Primary author

Prof. Bo-Qiang Ma (Peking University)

Presentation materials