Helicities (kinetic, magnetic, current, cross, etc.), as well as energies, are fundamental quantities of hydrodynamics (HD) and magnetohydrodynamics (MHD). In helical turbulence, mean-field structures (global vorticity, mean magnetic field, etc.) can be generated through a dynamo action by turbulent motions. Therefore, the dynamic and magnetic activities of the Sun and stars are intimately related to turbulent helicities. These relationships have been extensively investigated, both theoretically and observationally.
In the past, two Helicity Thinkshops, mainly on solar physics, were held in 2009 and 2013 at the National Astronomical Observatory of China (NAOC) at Beijing, China (Chair: Hongqi Zhang). They originated from a Chapman Conference on Magnetic Helicity in Space and Laboratory Plasmas held at Boulder, USA, in 1998 (Chair: Alexei Pevtsov). This time we organize a Helicity Thinkshop in Tokyo, Japan.

The aims of Helicity Thinkshop 3 are
(i) to share frontier knowledge on the topic of helicity stemming from observational investigations in astrophysics and geophysics, and from numerical simulations and experiments in fluids and plasmas;
(ii) to promote closer collaboration between different research fields involved in helicity studies (e.g., solar/stellar/geo, theory/modeling/experimental/observations);
(iii) to construct models of phenomena potentially influenced by helicity whose underlying physical mechanisms are not entirely understood.

Topics to be discussed
– insights on and estimates of helicity in the Sun and solar wind, helical structures on Earth and other astrophysical bodies;
– role of helicities in solar and stellar flares and in coronal mass ejections with an emphasis on space weather phenomena and their coupling with the Earth environment;
– role of helicities in dynamo theories and numerical modelling;
– sources of helicities in astro/geophysical context;
– future directions in helicity studies.

In order to enhance interdisciplinary communication, all speakers of the Thinkshop are expected to present their talks in plain, generic physics language.

Host Institutes:
Institute of Industrial Science (IIS), University of Tokyo
National Astronomical Observatory (NAOJ)

Sponsors:
IIS, University of Tokyo
Japan Society for the Promotion of Science (JSPS, for participants from Japan)
Russia Foundation for Basic Research (RFBR, for participants from Russia)

Scientific Organizing Committee:
Axel Brandenburg (Sweden/USA), Manolis Georgoulis (Greece), Kirill Kuzanyan (Russia), Raffaele Marino (France), Alexei Pevtsov (USA/Finland), Takashi Sakurai (Japan), Dmitry Sokoloff (Russia), Nobumitsu Yokoi (Chair, Japan), Hongqi Zhang (China)

Local Organizing Committee:
Nobumitsu Yokoi (Chair, University of Tokyo), Takashi Sakurai (NAOJ), Yoichiro Hanaoka (NAOJ), Masaoki Hagino (NAOJ), Shin Toriumi (NAOJ)

Venues of the Helicity Thinkshop 3:
Institute of Industrial Science (IIS), University of Tokyo
National Astronomical Observatory of Japan (NAOJ)

Preliminary Schedule:
Sunday, 19 Nov. Registration at IIS
from Monday, 20 Nov. to Thursday, 23 Nov. Scientific Talks and Discussions
including one session at NAOJ and tour to Solar Observatory

Registration fee will be in the range of $50-100 excluding the banquet.
The details of the registration procedure will be given later in forthcoming announcement.

Have you any questions or comments, please contact Nobumitsu Yokoi:
nobyokoi (at) iis.u-tokyo.ac.jp or Kirill Kuzanyan: kuzanyan (at) gmail.com