>>/66694/
Like a radiocoon, I don't know.
Nothing is "peanut" (in the idea of a class of devices) or "type x" with a cursory search, the search engines found it difficult to answer me at least somehow.
Perhaps an analogue of a diode (a device with one-way current conductivity), but somehow it looks too complicated for a diode.
It can also be a sensor of some high-energy (alpha and higher) radiation.
It glows in UV, because the inside is not a vacuum, but filled with some gas mixture.