Fusion reactions require that the atoms be raised to temperatures of millions of degrees.
It's Methods and Meanings . Atomic Education . Within 17 meters, the explosion temperature was 300,000 degrees Celsius. Within 50 meters it was 9,000-11,000 degrees, and at ground level beneath hypocenter the temperature exceeded 6,000 degrees. 300,000 K 9,000 - 11,000 K 6,000 K Ochi, Yukiko.