V. EVENTSRIKEN Accel. Prog. Rep. 54 (2021)

RIKEN Accel. Prog. Rep. 54 (2021)

Domestic Workshop on Spin Physics
Y. Goto,∗1 for the Local Organizing Committee
24th International Symposium on Spin Physics wasscheduled to be held in Matsue City in September 2020
as SPIN2020, but it was postponed to October 2021
because of COVID-19 pandemic and will be held as
SPIN2021. Prior to SPIN2021, we held a domestic
workshop on spin physics as a satellite workshop ofSPIN2021 on February 23rd and 24th, 2021 to discuss
future themes of spin physics and related ﬁelds, activities of various groups, and prospects for development
in Japan, as well as to provide a platform for presentations by young researchers. The workshop language
was Japanese.
In the workshop, topics related to spin phenomena inparticle and nuclear physics and related ﬁelds were discussed. In accordance with the topics to be discussed
in SPIN2021, the following topics were reviewed:• proton radius for the nucleon structure• RHIC and COMPASS results, three-dimensional
parton distribution, and QCD spin physics for thespin structure of hadrons• physics of the Electron-Ion Collider for future facilities and experiments• theoretical and experimental reviews for fundamental symmetries and physics beyond the standard model• polarized electron sources and solid polarized targets• physics at LEPS for spin physics research using
photon, lepton, and hadron probes• low-energy spin physics in nuclear reactions andnuclei• applications of spin physics

The workshop also included presentations by young
researchers on the understanding of the single-spin
asymmetry, nucleon structure studies based on the lattice ﬁeld theory, theory of the electric-dipole moment,
spin-spin correlation in K-pp decay, polarized targetof COMPASS, study of three-body nucleon force usinga polarized target, and structure analysis of materials
by neutron scattering. The presentations and discussions will be published and distributed as conference
proceedings.
SPIN2021 is planned to be held in October as a hybrid conference combining on-site and online sessions.
The domestic workshop was held at the same venue
as that for SPIN2021, the Kunibiki Messe Convention Center in Matsue City. Together with the venue
staﬀ, we discussed ideas for the success of the hybrid
conference and held the domestic workshop as a test
run of SPIN2021. Considering the current situation∗1Fig. 1. Setup of the venue for the hybrid conference.

of COVID-19, only the organizing committee participated on-site this time, while the others participatedonline. The number of on-site participants in the workshop was 7, and the number of online participants was45.
The on-site portion of the workshop was in the format of a regular research meeting in a conference room,
which was distributed via Zoom so that people could
participate online. The system shown in Fig. 1 wasprepared so that the online participants could participate in the question and answer session in the same
way as on-site participants. Some speakers and chairpersons spoke on-site, while others presented online.
The speakers at the venue displayed their slides on theprojector as in a normal conference, and the operator
distributed a split line to Zoom. The online speakers
also displayed their slides via Zoom screen sharing.
The workshop was held with ﬁnancial support fromthe RIKEN Nishina Center and with great help fromthe venue staﬀ. The hybrid conference method allowed us to integrate on-site and online discussions
and conduct an active workshop. We would like tobuild on the success of this experience to organize alarger SPIN2021 International Symposium with parallel sessions in addition to the plenary session, welcoming more on-site and online participants from abroad.

RIKEN Nishina Center- 197 -1