Thermal Radiation

Electromagnetic radiation emitted (in two pulses from a nuclear air burst) from the fireball as a consequence of its very high temperature; it consists essentially of ultraviolet, visible, and infrared radiations.

Electromagnetic radiations emitted from a heat or light source as a consequence of its temperature; it consists essentially of ultraviolet, visible, and infrared radiations. [JP1] 2. The heat and light produced by a nuclear explosion. [JP1]