Narrator: This is Science Today. Nuclear physicists at the Lawrence Livermore National Laboratory are working on developing smarter radiation detection technologies for cargo containers entering U.S. seaports. Dennis Slaughter says high sensitivity is key because the radiation that comes from a nuclear weapon is quite weak.
Slaughter: The problem is, its weaker than a whole lot of background sources present in the environment and its weaker than the radioactivity in a lot of legal shipments. Radioactive pharmaceuticals, various commercial cargo materials if you gather together thirty tons of some of this stuff, the radioactivity signals pretty large. And the radioactivity due to a nuclear weapon is a lot less than that.
Narrator: Slaughter says the obvious concern is the possibility of false alarms.
Slaughter: Were trying to build a system where the radiation we see is really distinctive, not like natural background, so that we can be sure that if we say, that's it, we think theres one there, that we wont be wrong about that any more than about one time in a thousand.
Narrator: Technical obstacles include figuring out how to detect nuclear materials even if terrorists have shielded the materials with lead. For Science Today, I'm Larissa Branin.