Study of the avalanche to streamer transition in the glass RPC exited by UV light

TL;DR

This study investigates the transition from avalanche to streamer discharges in a glass RPC exposed to UV light, analyzing how laser intensity and voltage influence the process, and capturing streamer propagation with imaging.

Contribution

It provides new insights into the avalanche to streamer transition in glass RPCs under UV excitation, including the observation of two streamer types and visual documentation of streamer propagation.

Findings

Transition depends on laser intensity and high voltage

Two types of streamer signals observed

Streamer propagation visualized with CCD camera

Abstract

A small glass RPC filled with Ar/Isob./Freon mixture has been exposed to a UV laser light. Avalanche and streamer regimes of discharge were reached in a fixed region of the RPC exited by the UV. A dependence of avalanche to streamer transition process on the laser beam intensity and on the applied high voltage was studied. Two types of the streamer signal have been observed. Using a CCD TV camera, pictures on multi-streamer propagation over RPC were obtained.