Signature and decades of signature databases and modelling to generate signatures via decay chains, etc.
Signatures being patterns in gamma ray spectrums with 256 or more channels.
You can boost signatures with long soak times and SVD stuff.
A more challenging question might be how much cosmic and cosmic decay byproduct do they have to filter away on what kind of orbit related time series fluctuation as a levelling correction.
How does this distinguish between radioactivity from a nuclear weapon and radioactivity from a nuclear reactor?
Signature and decades of signature databases and modelling to generate signatures via decay chains, etc.
Signatures being patterns in gamma ray spectrums with 256 or more channels.
You can boost signatures with long soak times and SVD stuff.
A more challenging question might be how much cosmic and cosmic decay byproduct do they have to filter away on what kind of orbit related time series fluctuation as a levelling correction.