TFLYTSNBN wrote:
Kinetic energy of the fusion fuel and fusion products, yes.
Remember, aside from Gamma rays emitted from either fission products or fusion products, most of the EM radiation from a nuke is X-rays emitted over a considerable time (relative to the actual time the fission/fusion reaction occurs) emitted by the ionized plasma that was the bomb.
Oh, I forgot, chunks of bomb casing can actually survive the detonation. They used to find them scattered around on the ground after atmospheric testing. This of course inspired Dr Van Allen which led to the nuclear test that resulted in Dr Van Allen loosing his balls.
Basically you project a very large fraction of the burst energy in a 5.9 degree cone composed of material moving at about 1,000 km sec.
There was also the early underground tests where the space above the 900 kilo tunnel cover was bring filmed by a camera running at 1,000 frames per second, to see what happened to the cover and measure it's velocity. Sadly it only appeared in one frame, which means it was moving at at least 100,000 km/hour. It's unclear if went into solar orbit or if it burned up in the atmosphere due to friction.