alt Hacker News There's been a lot of development since this dissertation to let it run in real time, and to integrate with tactical radiation detectors that the military/police/civil defense teams tend to use. Unfortunately that's mostly unpublished work at present.
Australia had some fun with a lost mining source - rather than run a geophysics plane 80m above ground from mine to city they held off to test a gadget with some whirly stuff about a crystal pack ... as I understand it.
Any comment, or all still a bit unpublished?
Not us, but probably an imaging radiation detector with LIDAR. Its another technology for search, with its own tradeoffs and advantages. We are friends with a couple companies that make that tech, but it's a different thread of R&D. Arguably a bit more mature; doing localization like we do with "normal" detectors on the ground is pretty challenging. We've done pretty realistic joint exercises with the military with our tech (called QkRad) but nobody has actually fielded it in a real emergency yet. We are around TRL 7 if you know that terminology.
These sort of loss events happen much more often than is reported widely. Not like something that happens every day, but there are a non negligible number of events every year. The Nuclear Threat Initiative catalogs publicly known events if you want to browse.