Can one see a flower through a granite wall? Amazing capabilities of neutron imaging

The detection technology which we developed for NASA astrophysical missions at UC Berkeley's Space Sciences Laboratory has been successfully extended to such diverse areas as synchrotron instrumentation, biomedical imaging, ground-based astronomy and neutron microtomography. In this talk I will briefly describe some instrumentation we built for NASA satellites, in particular for the last Hubble repair mission, and how the same technology enables novel non-destructive testing methods utilizing neutrons. These reveal processes happening inside and behind thick objects. The fact that neutrons interact with the nucleus, as opposed to electrons in the case of x-rays, leads to a very different contrast mechanism. As a result, most organic objects are quite opaque and many metals can be easily penetrated. That allows seeing a drop of oil or gasoline inside a real aluminum-block car engine, a flower behind a granite wall, water flow inside metal pipes, strain in materials, etc. The latter can be very helpful for the engineering studies of crack formation in metals, preventing the fatigue of structures used in bridges and buildings. Also, the interaction of neutron spin with magnetic fields allows high resolution measurements of magnetic fields inside and around thick objects. A number of proof-of-principle experiments performed at continuous and pulsed neutron sources will be discussed, as will possible applications.

Speaker: Anton Tremsin, UC Berkeley

Room 100