Wiktionary
soft x-rays
n. (soft X-ray English)
Usage examples of "soft x-rays".
My skin is an exotic armor, pebbled with monocrystalline diamonds held in a shock-absorbent quantum dot matrix that can be fast-tuned to match the color of any background from radio frequencies through to soft X-rays.
The air absorbed much of the soft X-rays and was burned into an opaque mass which stopped further electromagnetic radiation, transforming it into mechanical energy that expanded at several times the speed of sound, but before that energy had a chance to damage anything, more distant events were already underway.
Their instruments detected weak radio emissions and bursts of soft X-rays from the sunspot group.