Radiation survey, under Nuclear MASINT, is an area operation, or will measure the effects on specific people or things.
A materials MASINT analyst looking at the same phenomenon, however, will have a more micro-level view, doing such things as analyzing fallout particles from air sampling, ground contamination, or radioactive gases released into the atmosphere.
[3] The survey function measures the type of active ionizing radiation present from:[4] While alpha particle emitters such as those in depleted uranium (DU) (i.e., uranium 238) are not a hazard at a distance, alpha particle measurements are necessary for safe handling of projectile dust, or of damaged vehicles with DU armor.
The basic field survey instrument that can detect alpha particles is a scintillometer, such as the AN/PDR-77, which "shall accept a maximum of eight different probes.
An accessory kit is available that contains a GM pancake probe and a 1” x 1.5” NaI micro-R probe.various removable shields to permit alpha and beta particles to reach the sensor."
Typically, the capabilities include gamma spectroscopy, low background counting for very thin alpha- and beta-emitting samples, and liquid scintillation counters for extremely low energy beta emitters such as tritium.The DoD directive makes the distinction clear that detection is harder than measurement, and the latter is necessary for MASINT.
Not surprisingly, the quantitative relationship between the amount of radiation actually emitted and the reading on the meter is a complex function of many factors.
Detectors based on semiconductors, notably hyperpure germanium, have better intrinsic energy resolution than scintillators, and are preferred where feasible for gamma-ray spectrometry.
Liquid scintillation counters are an efficient and practical means of quantifying beta radiation Some reactor accidents have left extremely high levels, such as at Chernobyl or the Idaho SL-1.
A significant fraction of the energy generated by a nuclear reactor is lost in the form of extremely penetrating antineutrinos, with a signature revealing the kind of reactions inside.
[5] Initially held back by a lack of spectrum data, in the early 2000s, with increased resolution, the process has been demonstrated in Canada and is suggested as possibly useful for remotely monitoring the proposed reactors within the Iran nuclear energy program.
[6][7][8][9] The multinational Daya Bay Reactor Neutrino Experiment in China is currently (as of 2016) the world's most important research facility in this field.
When, for example, ex-Soviet submarine reactors are not given full maintenance or decommissioning, there is a cumulative hazard that steel in the containment, or piping that can reach the core, might lose strength and break.
Understanding those effects as a function of radiation type and density can help predict when poorly maintained nuclear facilities might become orders of magnitude more hazardous.