creates plasma

As Mikoto’s thoughts floated up into the air, Accelerator sneered as he spread his arms
wide up into the night sky. In the next instant, the wind flowing through the city focused
on one point. It was a point 100 meters above Accelerator’s head. When the raging wind
gathered there, a bright white light appeared as if from welding.
It was plasma.

Compressing the air created heat. Internal combustion engines used that fact. By
compressing the city’s air with a ridiculous compression ratio, it had turned into a mass
of heat exceeding 10,000 degrees Celsius. This forcibly caused the atoms in the nearby
air to split into cations and electrons which turned them to plasma.
That point of light swallowed up the surrounding air and instantaneously grew to have a
radius of 20 meters.
The surrounding darkness was annihilated by the pure white light.
The heat of 10,000 degrees caused a burning pain on Mikoto’s skin.
A chill ran down Mikoto’s back that seemed to freeze her spine.
That was not an attack that humanity could defend against. That mass of heat could dig
up a nuclear shelter from the ground, so there was no way a flesh-and-blood body could
do anything about it.

- Toaru Majutsu no Index Volume 3, Chapter 4 Part 7