KEK Workshop on GPDs and related topics at J-PARC


2021/12/22 09:00 – 17:45


Online (Zoom)






Generalized parton distributions (GPDs) are a type of three-dimensional
structure functions of hadrons. Recently, there was experimental progress
on the GPDs, and it is one of major projects at future electron-ion
colliders in US and China (EIC, EicC) in 2030’s. In addition,
the GPD measurement could become possible by using the neutrino beam
at Fermilab.

From the GPDs, we expect that partonic orbital-angular-momentum contributions
to the nucleon spin will become clear, and gravitational form factors
will be obtained. Therefore, the GPD studies will lead clarifications
on origins of hadron spins and masses.

On the other hand, there were already measurements on timelike GPDs
at KEKB, and gravitational form factors of a hadron were obtained
from the actual experimental data for the first time. It was listed
as one of highlight research results from KEK in the annual report
of 2019.

At J-PARC, we expect to have a new proposal on the GPD measurement
in 2022 by using the high-momentum beamline (essentially pions).
There is already approved experiment E50 on charmed baryons
at this beamline, and the GPD experiment is considered
by extending this experiment for exclusive Drell-Yan processes.
At this workshop, we discuss this J-PARC GPD experiment together
with related topics. If you are interested in the workshop,
please register from the workshop indico page until December 17.
We will send you the zoom information on December 20.

We are looking forward to seeing you at the workshop.

Discussion topics

  • Generalized parton distributions (GPDs)
  • Related experimental projects
  • Gravitational form factors
  • Compositions of hadron spins and masses
  • High-energy hadron interactions, Color transparency

Style: Online by using zoom.

Registration: Please register from the conference web page until Dec.17.
Zoom information will be sent for registered participants on Dec.20.

Organizer: Shunzo Kumano (KEK/J-PARC) [shunzo.kumano(AT)]
Inquiry: Please send email to gpd-j-parc21(AT)
(to S. Kumano, Secretary: K. Iioka)

Release date 2021/12/22 Updated 2024/03/02