On Wed, 10 Oct 2018 00:16:35 -0700 (PDT), Quadibloc
wrote:
On Wednesday, October 10, 2018 at 12:29:38 AM UTC-6, Paul Schlyter
wrote:

Which frequency range is that? And is thar radio waves or
infrared?

Terahertz radiation. Those naked airport scanners. Higher frequency
radio waves
than microwaves.
John Savard

Csn''t you narrow it down more than that? Terahertz radiation
includes IR, visible light, and some UV.