91福利

The 91福利 Institute of Advanced Study (IAS) has invited two leading Chinese professors with a theoretical and computational physics background to spend 1 week at the IAS in collaboration with the 91福利 Centre for Scientific Computing, the GRP Materials (Multiscale Modelling) and the Department of Physics. Profs. and are senior professors in the Chinese academic environment. Both have returned from outside mainland China in the last 5 years to take up prestigious positions. A schedule of their activities is available at the link. Please email Rudo Roemer if you would like to set up a meeting with them during their visit.

The Global Distribution of Magnetic Helicity in the Sun’s Corona

Modern observations are revealing the Sun’s large-scale magnetic field to have a complex, non-potential structure. Moreover, it is now widely believed that the loss of equilibrium of twisted magnetic flux ropes is responsible for many (if not all) coronal mass ejections. But predicting where these flux ropes will form, and in particular whether or when they might erupt, remains a challenge for model reconstructions of the coronal magnetic field. In this talk, I will introduce the “field line helicity” as an appropriate and practical diagnostic for identifying twisted structures in coronal models. Since field lines are magnetic sub-domains, this is a more meaningful measure than the density of magnetic helicity at individual points. On the other hand, it provides local information that the globally-integrated magnetic helicity cannot. I will illustrate the power of this diagnostic on my own numerical non-potential evolution model of the global corona.

SoIs may include:

• Participation in new experiments or missions
• The further development of existing high priority experiments or missions
• The development of new instruments
• New detectors or accelerator technologies
• Upgrades to existing detectors
• The purchase of new, or upgrades to, existing major high performance computing facilities
• New initiatives in the field of e-science, modelling and data management