difference between X-ray and neutron absorption Little Boy neutron flux Baratol Fat Man radiation Nagasaki
The reported threshold dose variance between the two cities is suggested to be a manifestation of the difference between X-ray and neutron absorption, with Little Boy emitting substantially more neutron flux, whereas the Baratol that surrounded the core of Fat Man filtered or shifted the absorbed neutron-radiation profile, so that the dose of radiation energy received in Nagasaki was mostly that from exposure to X-rays/gamma rays.