Abstract
The stable high-speed and thin film flow (30 m/s in velocity and 0.6 mm in thickness) of liquid lithium was successfully formed on a wall for the neutron source in Boron Neutron Capture Therapy (BNCT), which makes cancers and tumors curable with cell-level selections and hence high QOL. The object of our research is to materialize the thin and high-speed wall film flows of liquid lithium in a high-vacuum (10^<-3> Pa) as an accelerator target. We proved that it is neutrally stable within the limits of linear stability theory under the short wave approximation on the basis of the wave length, λ≈2 mm, measured from the photographs (10 μs in shutter speed) of the ripples on the surface of the film flow. The locus of experimental points (Re, k) on the Re-k plane seems to be located across the unstable region surrounded with a critical curve of neutral stability.
