Prof. Xiangdong Ji
, Univ. of Maryland
[Host: Xiaotong Song]
While the form factors and parton distributions provide separately
the shape of the proton in coordinate and momentum spaces, a more
powerful imaging of the proton structure can be obtained through
phase-space distributions. In this talk, I introduce the Wigner-type
quark and gluon distributions which depict a full-3D proton at every
fixed light-cone momentum, like what is seen through momentum
("color")-filters. After appropriate phase-space reductions, the
Wigner distributions are related to the generalized parton distributions
(GPD's) and transverse-momentum dependent parton distributions, which
are measurable in high-energy experiments. The new interpretation of
GPD's provides a classical way to visualize the orbital motion of the
quarks, which is known to be the key to the spin and magnetic moment
of the proton.
High Energy Physics Seminar
Wednesday, April 16, 2003
Physics Building, Room 204
Note special time.
Note special room.
Special Nuclear and High Energy
To add a speaker, send an email to
Please include the seminar type (e.g. High Energy Physics Seminars), date, name of the speaker, title of talk, and an abstract (if available).