Hybrid torus as an active space radiation shielding

Question

Lately, I was studying the possible methods for protecting astronauts and onboard equipment in a spacecraft from space radiation which mainly comprises solar particle events (SPEs) and galactic cosmic radiation (GCR) and poses the major hurdle. After reading a lot of papers on this topic, I am convinced that magnetic shielding is one of the best choices and an active area of research. I encountered the most effective shape of the shielding to be a hybrid torus. But unfortunately, none of the papers properly describe the hybrid torus. Can anyone please help me understand the geometry of hybrid torus and how it is effective as compared to other shapes regarding active magnetic shielding against space radiation?

Link of the paper: https://www.dartmouth.edu/~sshepherd/research/Shielding/docs/Bernert_64.pdf

Answer 1

A hybrid torus appear to be what you get if you take a torus and stretch it out so that it becomes a near-sphere.

(picture from Townsend, L. W. (1983). HZE particle shielding using confined magnetic fields. Journal of Spacecraft and Rockets, 20(6), 629-630.)

Imagine taking a torus and having an electric current running around its surface along the latitude lines. This will produce a magnetic field in the interior of the torus that deflects particles. But it is inconvenient to live and work in a strong magnetic field. The central hole is field-free and somewhat protected, but obviously cosmic rays can enter from some directions. So the hybrid torus deforms the torus into a near-sphere with and internal spherical "hole" connected to the outside world by two polar tunnels. The walls are full of current and the space between the spheres have deflecting magnetic fields. So the only thing that remains to do is to add some shielding above and below the tunnels, and the interior is nicely shielded.

How effective is it? The Townsend paper thinks this works well for solar particles but not the heavy ion cosmic rays of space. Still, if you have superconducting coils it seems to be a good configuration and other related toroidal geometries have been simulated using modern technology. But as Townsend pointed out in 2004, a lot of these analyses ignore inconvenient parts of the radiation spectrum, whether the full equipment for the shield is lighter and more manageable than a simple passive shield, and whether the engineering details of very strong fields have all been worked out.